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Board of Professional Engineers Queensland v Jenkins[2015] QCAT 553

Board of Professional Engineers Queensland v Jenkins[2015] QCAT 553

CITATION:

Board of Professional Engineers Queensland v Jenkins [2015] QCAT 553

PARTIES:

Board of Professional Engineers Queensland

(Applicant)

 

v

 

Colin Jenkins

(Respondent)

APPLICATION NUMBER:

OCR097-13

MATTER TYPE:

Occupational regulation matters

HEARING DATE:

16, 17 and 18 June 2015

HEARD AT:

Brisbane

DECISION OF:

Member Ann Fitzpatrick

DELIVERED ON:

10 December 2015

DELIVERED AT:

Brisbane

ORDERS MADE:

  1. The application is dismissed.
  2. The respondent Colin Jenkins is to file and serve any submissions in relation to costs by 4pm 5 January, 2016.
  3. The applicant Board of Professional Engineers Queensland is to file and serve any submissions in relation to costs by 4pm 26 January, 2016.

CATCHWORDS:

PROFESSIONS AND TRADES – ENGINEERS – GENERALLY – where respondent was professional engineer – disciplinary action – unsatisfactory professional conduct

Professional Engineers Act 2002, s 36, s 73(2), s 127

APPEARANCES:

 

APPLICANT:

Board of Professional Engineers Queensland

RESPONDENT:

Colin Jenkins

REPRESENTATIVES:

 

APPLICANT:

represented by Mr Scott Seefeld of Counsel, instructed by Holding Redlich Lawyers

RESPONDENT:

represented by Mr Jonathon Priestley of Senior Counsel, instructed by CH Law

REASONS FOR DECISION

Orders sought

  1. [1]
    By further amended application, filed 17 April, 2015, the applicant Board of Professional Engineers Queensland (the Board) seeks the following Orders from the Tribunal:
    1. (a)
      that a disciplinary ground has been established pursuant to section 36 of the Professional Engineers Act 2002 (the Act) for the disciplining of the respondent Mr Colin Jenkins in that he has behaved in a way that constitutes unsatisfactory professional conduct as defined in the Act, namely:
      1. conduct that is of a lesser standard than that which might reasonably be expected of a registered professional engineer by the public or the engineer’s professional peers; and
      2. conduct that demonstrates incompetence or lack of adequate knowledge, skill, judgment or care, in the practice of engineering;
    2. (b)
      that Mr Jenkins be reprimanded pursuant to section 131(3)(a) of the Act;
    3. (c)
      that a penalty for a stated amount be imposed on Mr Jenkins pursuant to section 131(2) of the Act; and
    4. (d)
      that the respondent pay the Board’s costs of and incidental to the proceedings pursuant to section 102 of the Queensland Civil and Administrative Tribunal Act (the QCAT Act) including the Board’s investigation costs.

Jurisdiction of the Tribunal

  1. [2]
    By s 127 of the Act, this Tribunal may, on application by the Board, conduct a disciplinary proceeding to decide whether a disciplinary ground is established.

Allegations against Mr Jenkins

  1. [3]
    Mr Jenkins is the principal of Col Jenkins & Associates Pty Ltd. Mr Jenkins was engaged by Perry Homes (Aust) Pty Ltd (Perry) to provide professional engineering services in respect of residential building work performed by it.
  2. [4]
    The Queensland Building Services Authority (QBSA) was the predecessor of the current Queensland Building and Construction Commission. Mr Gary Stick, Resolution Manager employed by the QBSA lodged with the Board, a Form 6 Complaint, dated 15 March 2011 against Mr Jenkins. The complaint alleged unsatisfactory professional conduct. The complaint arose out of complaints by homeowners and claims on the insurance fund, with respect to subsidence related matters for dwellings constructed by Perry. Mr Jenkins provided engineering services in relation to those dwellings.
  3. [5]
    The Board conducted investigations and decided to start disciplinary proceedings against Mr Jenkins, pursuant to s 73(2) of the Act.
  4. [6]
    The disciplinary proceedings are taken against Mr Jenkins in relation to site investigations and preparation of geotechnical reports for the following sites:
    1. (a)
      42 Neptune Street, Springfield Lakes (Neptune);
    2. (b)
      72 Greenway Boulevard, Maudsland (Greenway);
    3. (c)
      15 Shergar Court, Jimboomba (Shergar);
    4. (d)
      16 Amadeus Court, Springfield Lakes (Amadeus);
    5. (e)
      6 Killarney Court, Ormeau (Killarney);
    6. (f)
      Lot 133 Banksia Drive, Raceview (Banksia);
    7. (g)
      35 Brittany Crescent, Raceview (Brittany 35);
    8. (h)
      43 Brittany crescent, Raceview (Brittany 43);
    9. (i)
      40 C Zahnows Road, Rosevale (Zahnows);
    10. (j)
      103 Carrigan Way, Gleneagle (Carrigan);
    11. (k)
      1 Caithness Court, Toowoomba (Caithness).
  5. [7]
    The disciplinary proceedings are also taken against Mr Jenkins in relation to the footing design system at each of the above sites, except for Banksia, Brittany 35 and Brittany 43.
  6. [8]
    In summary, the Board submits that:
  1. (a)
    Mr Jenkins did not comply with the requirement of AS2870 that all sites must be classified in accordance with section 2 of the standard;
  2. (b)
    For almost all sites Mr Jenkins has assigned a class S. Mr Jenkins cannot have properly carried out any of the methods set out in AS 2870 for site classification, being identification of the soil profile and a classification from either established data or current performance of houses on the soil profile; or estimation of the characteristic surface movement.
  3. (c)
    AS2870 requires that the soil profile is to be examined to not less than 1.5m with a minimum of one borehole per house site. The Board submits that Mr Jenkins has not undertaken this examination.
  4. (d)
    For many sites, there was a significant under-estimation of the reactivity of the site classification. The consequence was footing system designs with significantly less stiffness than the standard designs under AS2870 for the actual site classification; and a substantially diminished ability to resist soil movements.
  5. (e)
    Mr Jenkins geotechnical reports were addressed to the local government and purported to comply with AS2870, however they did not comply because the site classification did not comply with AS2870 and no information was provided on how the classification was obtained.
  6. (f)
    The reports provide a soil profile, including depths of various soil types which implies that actual boreholes have been dug at the site, when they were not. Further, in the absence of actual boreholes, the soil profiles in the reports are, at best, an “educated guess” and at worst a “fiction”.
  7. (g)
    It is concluded that the public and professional peers expect compliance with the relevant Australian standard. AS2870 is intended to protect the public from the consequences of poor footing system design. Deficient footing systems are not readily observable and are difficult and expensive to rectify. Mr Jenkins is said to have fallen short of those expectations.
  8. (h)
    Finally, it is said that Mr Jenkins’ conduct also demonstrates a lack of judgment and care in the practice of engineering and his efforts to circumvent the requirements of AS2870 cast serious doubt on his judgment.
  1. [9]
    The Board has particularised its allegations in the Further Amended Application.

Mr Jenkins response

  1. [10]
    In summary, Mr Jenkins submits that:
    1. (a)
      There is no allegation by the Board that as a result of any of the 11 designs, any damage was suffered by any member of the public or any other person or entity.
    2. (b)
      His approach is specifically provided for by AS2870.
    3. (c)
      There needs to be evidence of Mr Jenkins’ peers to establish the expectation of his peers. Mr Fox, the expert witness called by Mr Jenkins, gives the only evidence of a peer. The expectations of the public do not go beyond what is established by Mr Fox. The public expectation would be for the engineering designs to work. It is submitted that they do.
    4. (d)
      The recurring theme in the complaints made against him is that he does not carry out laboratory testing in making a site classification, nor does he follow the deemed to comply design provisions.
    5. (e)
      Mr Jenkins has classified each of the sites as “P”. Where the site is “P” the classification provisions of section 2.2 of AS2870 do not apply, nor do the deemed to comply design provisions apply. In any event the method of determining soil reactivity used by Mr Jenkins falls within AS2870, even though laboratory testing has not been used.
    6. (f)
      The method used by Mr Jenkins led to footing designs which are performing and which are now quite aged so that any potential damage ought to have become apparent.
    7. (g)
      The reports prepared by Mr Jenkins are not for use by a local authority, but are only for his use and therefore cannot be inadequate or misleading.

Relevant issues

  1. [11]
    It is relevant to make findings in relation to the following matters:
    1. (a)
      Whether any of the slabs in question have failed to perform adequately;
    2. (b)
      Whether Mr Jenkins has complied with AS2870 in his site investigations and techniques and whether he is obliged to do so;
    3. (c)
      Whether the footing systems designed by Mr Jenkins are inadequate for the sites on which they were constructed;
    4. (d)
      The use to which Mr Jenkins site reports are put and in that context whether they are inadequate or misleading;
    5. (e)
      Whether the grounds for disciplinary proceedings taken against Mr Jenkins are established with respect to the 11 sites in question;
    6. (f)
      Whether there has been conduct on the part of Mr Jenkins in relation to his work on the 11 sites referred to in the proceedings which falls below the expectations of his peers and the public; and
    7. (g)
      Has there been demonstrated incompetence, or a lack of adequate knowledge, skill, judgment or care in Mr Jenkins’ practice of engineering.

Evidence

  1. [12]
    I have had reference to the affidavit of Gary Stick, then Resolution Manager of the QBCC, sworn 8 July 2013 (Exhibit 1); oral evidence given by Mr Stick; the affidavit of Clare Murray, Registrar of the Board, sworn 26 June 2013 (Exhibit 2); the affidavit of Peter Davis, Geotechnical Engineer, affirmed 2 July 2013 (Exhibit 3); statement of Peter Davis, made 16 April 2015 (Exhibit 4); the oral evidence of Mr Davis; affidavit of Eric Fox, sworn 5 June 2015 (Exhibit 5); supplementary report of Eric Fox, filed 16 June 2015 (Exhibit 6); the oral evidence of Mr Fox; joint expert report of Peter Davis and Eric Fox following an experts’ conclave held on 29 May 2015; Australian Standard 2870 – 1996 together with appendices and supplement (Exhibit 7); affidavit of Colin Jenkins, sworn 21 May 2015 (Exhibit 8); affidavit of Colin Jenkins, sworn 16 June 2015 (Exhibit 9) and the oral evidence of Colin Jenkins.
  2. [13]
    Mr Jenkins has been a qualified Professional Civil/Structural engineer since 1964 (Chartered since 1968). He has operated his own consulting practice since May 1980. Mr Jenkins’ curriculum vitae reveals that he has been involved with design, construction and supervision on all kinds of civil and structural engineering projects for over 50 years, including more than 17,000 buildings during the last 34 years, of which over 16,000 would be residential housing, including all geotechnical investigations.
  3. [14]
    Mr Jenkins has been a registered professional engineer in Queensland from 1975 to 1978 and from 1982 to date. He has been a Fellow of the Institution of Engineers of Australia for 20 years. He holds membership of a large number of professional bodies including the Australian Geomechanics Society, the International Society of Rock Mechanics, the International Association of Engineering Geology, and International Society for Geotechnical Engineering.
  4. [15]
    Mr Jenkins impressed me as a truthful witness. I formed the view that he was very experienced in design of residential footing systems and knowledgeable in relation to geological features of building sites. I noted him to be unshakeable in cross-examination. I have no reason not to accept his evidence.
  5. [16]
    Mr Eric Fox was called by Mr Jenkins as an expert witness. Mr Fox is the principal of EFC Consulting Engineers, a specialist engineering consultancy in the field of forensic structural and geotechnical engineering, structural and geotechnical research, and product and standards development. Relevant to this case, Mr Fox is Chairman of the AS2870: Residential slabs and footings code (BD025) committee; Chairman of the AS4349; Inspection of building code (BD085) committee; Chairman (past) Housing Performance Code committee and Member (past) of the General design of structures and loading (BD006) committee.
  6. [17]
    I found Mr Fox’s experience and expertise to be helpful to the Tribunal, particularly in relation to design of residential footings and slabs and site classification methods. He remained firm in his opinions under cross-examination.
  7. [18]
    Mr Davis is a registered professional engineer. At the time of his investigation and the reports prepared for the Board he was a senior geotechnical engineer in the employ of Cardno (Qld) Pty Ltd. Mr Davis has expertise in geotechnical site investigations, however he has worked mainly on large commercial projects rather than residential construction. Mr Davis acknowledged that he does not have the expertise to express an opinion on design features of residential footing systems. That acknowledgment during the course of the hearing altered the evidence available to the Board in relation to a key part of its complaint against Mr Jenkins. I will discuss this issue later in the decision, however, Mr Davis also appeared to have formed his opinions in relation to the conduct of Mr Jenkins on the basis of two critical misunderstandings. First that Mr Jenkins had classified the sites in question as “S” and second that he had designed the footing systems for class “S” sites. Mr Davis perpetuated those misunderstandings despite explanation by Mr Jenkins. Because of these matters in any contest of opinions between the experts I prefer the evidence of Mr Fox. I am also confident in Mr Fox’s expertise in relation to the matters before me.

Performance of the slabs

  1. [19]
    The Board has not formally asserted as a ground for disciplinary proceedings that any of the slabs on the sites in question are not performing. Its contention is that the footing system is designed for a wrong site classification and without proper assessment of soil reactivity. Despite this position, the Board’s witnesses have raised non-performance of the footing systems, lack of suitability of the footing systems and the prospect of the failure of the footing systems over a building’s 50 year life span.
  2. [20]
    The complaint which generated these proceedings was made by Mr Gary Stick, then Resolution Manager of the QBCC. His complaint is that a significant number of residential buildings constructed to soil tests and engineering designs provided by Mr Jenkins have come to the attention of the QBCC through homeowner complaints.
  3. [21]
    He expresses the opinion in his complaint to the Board, dated 15 March 2011, that the engineering practices of Mr Jenkins have led to significant under classification/incorrect classification of soil types resulting in dwellings being constructed that are not performing or that have a high level of expectation of non-performance over the design life of the structure.
  4. [22]
    In cross-examination Mr Stick said that 5 sites came to the attention of the QBCC as a result of consumer complaint. The homes were rectified and the files closed. The remaining 6 sites which the Board has raised in its disciplinary proceedings came to Mr Stick’s attention through phone calls from other builders. Mr Stick had no record of the conversations or the names of the builders. Of those 6 sites, Mr Stick bought 3 sites to the attention of Mr Davis, the investigator appointed by the Board, after his investigation had begun. None of those 6 sites involved any complaint by a homeowner. Mr Stick’s explanation for raising the extra 6 sites with the Board, in the absence of homeowner complaint, is that he was sufficiently concerned about Mr Jenkins methodology to be concerned for consumers and the prospect of future payouts having to be made in relation to subsidence issues.
  5. [23]
    In relation to the complaints by homeowners, Ms Clare Murray, Registrar of the Board, filed an affidavit in relation to the steps taken by the Board with respect to this matter. She was not required for cross-examination. Her affidavit attached all the reports and investigations undertaken by the QBCC and the Board in relation to the sites in question. The parties agreed that geotechnical data in these reports would be in evidence only as data and not for the conclusions reached by the authors of the various reports. The parties agreed that allegations against Mr Jenkins had to be proved through Mr Davis.
  6. [24]
    With respect to the sites where there were homeowner complaints, I note that NJA Consulting Pty Ltd prepared reports for the QBCC in relation to the Amadeus, Greenway and Killarney Court sites, and recorded that all three sites exhibited surface drainage deficiencies. At the Amadeus site cracking reported was Category 0 (negligible) to Category 2 (slight), with some Category 3 (significant) damage in a couple of spots. The Categories are based on Table 1 in appendix C, attached to AS2870. At the Greenway site damage was reported as Category 0 to Category 2, however, there was a distinct opening of the slab joint at the rear of the house. At the Killarney Court site cracking was reported as Category 0 to Category 2.
  7. [25]
    Bennatt Ground Technologies Pty Ltd, prepared a report for QBCC which recorded that at the Neptune site, damage had occurred to the structure, exacerbated by poor drainage and broken pipes. The damage to the dwelling was classified as between damage category 0 to category 3. The Bennatt Ground Technologies report in relation to the Shergar site recorded that building damage and slab/footing movement had occurred. It noted abnormal moisture conditions adjacent the footings. It concluded that the category of damage was between category 0 to category 2 based on Table 1 in Appendix C, attached to AS2870 – 1996.
  8. [26]
    There is no dispute between the parties that abnormal moisture conditions were present in relation to the 5 sites where homeowner complaints were made. There is no dispute between the parties that damage sustained by the dwellings was not substantial.[1]
  9. [27]
    Mr Jenkins gave evidence that no claim has been made against him by the QBCC in relation to any of the sites, except one, which is the subject of District Court proceedings and which he is defending. No evidence is before this Tribunal in relation to that matter.

Finding

  1. [28]
    I find that abnormal moisture conditions, over which Mr Jenkins had no control were present in relation to the Neptune, Shergar, Amadeus and Killarney Court sites. I accept the evidence of Mr Fox that abnormal moisture conditions, not the responsibility of Mr Jenkins, were causative of damage on all but the Greenway site. I accept Mr Fox’s opinion that at the Greenway site, inadequate founding of piers at the rear of the house was causative of damage, however that was not the responsibility of Mr Jenkins. I find that in any event, damage sustained by the dwellings at these sites was not substantial.
  2. [29]
    The other areas related to performance of the footing systems raised by the Board’s witnesses are:
    1. (a)
      Alleged inadequacy of the footing systems on 7 sites, given what the “deemed to comply” designs in AS2870 require; and
    2. (b)
      The prospect that slabs designed by Mr Jenkins may not perform adequately over an anticipated life of 50 years.
  3. [30]
    I will deal with the first point later in this decision. In relation to the latter point, I note the concern expressed by Mr Stick and Mr Davis. Mr Stick said in re-examination at the hearing that sometimes problems with a building emerge outside the QBCC’s period of limitation of 6 years 3 months and that he had a concern for the design life of a 50 year building. He said that it may be that under-designed buildings underperform over a 50 year life. He acknowledged that he did not have any statistics in relation to this proposition.
  4. [31]
    In cross-examination Mr Davis asserted in relation to the Neptune site that although the slab has not mal-performed it still has a long way to go. In relation to the Shergar site, Mr Davis acknowledged that after 11 years the slab is performing. It was put to Mr Davis that he says the slab may not perform for its 50 year life, however he has no expertise to say that and no evidence to back it up. Mr Davis said that his view as to long term performance was based on a comparison of the stiffness in deemed to comply designs in the Australian Standard for a reactive site. This is consistent with the conclusion expressed in his report dated 14 January 2013 that:

This under-classification of building sites can be expected to result in footing slabs being less able to withstand soil movements than those designed using the accepted practices of AS2870.[2]

  1. [32]
    Mr Davis acknowledged in cross-examination that he had not checked to see if any similar 25 year old slabs designed by Mr Jenkins were performing. He also acknowledged that he had no expertise in residential footings and slabs and that he would prefer not to give an opinion on design issues. Mr Davis confirmed that he is a geo-technical engineer.
  2. [33]
    Mr Fox expressed the opinion in his report dated 5 June 2015, that Mr Jenkins slab and footing designs are sound and that they are performing. Mr Fox also said that in his opinion it is not technically proper to determine that a system (such as that used by Mr Jenkins) is inappropriate through simple comparison with deemed-to-comply alternatives, if the opportunity exists to assess the actual physical performance of the system. He said that if a substantial number of houses have been designed using the same system, and those houses have been performing adequately over a number of seasonal moisture cycles (particularly if the houses were built in drought and have since been exposed to normal rainfall), then it is reasonable, prima facie, to assume that the system is acceptable. I accept that evidence.
  3. [34]
    Mr Jenkins gave evidence that he has prepared some 16,000 designs, including 8,000 for Perry Homes using the same design philosophy on sites with similar characteristics. He swore that he was unaware of non-performance on any site other than for a claim made in 2015 which he is defending. I accept that evidence.
  4. [35]
    Mr Jenkins submits that there is no evidence of poor design of the slabs in question before me that might lead to future non-performance. He submits that Mr Fox gave evidence that the design is appropriate and that it is performing. He submits that an inference can be drawn that if slabs are now performing they will keep performing.

Finding

  1. [36]
    In relation to the complaint made by the Board’s witnesses Mr Stick and Mr Davis that Mr Jenkins’ footings and slabs may not perform adequately for a lifespan of 50 years, there is insufficient evidence to justify the complaint. I am unable to find that the footings and slabs in question may not perform adequately over a 50-year lifespan. Mr Stick is not qualified to make such a prediction. His evidence at its highest is the expression of a concern about future performance. Mr Davis has acknowledged that he does not have sufficient expertise to comment on questions related to the adequacy of design of footings and slabs. The Board’s witnesses have not made any enquiry as to the adequacy of performance of much older footings and slabs designed by Mr Jenkins in a similar way for use in similar soil profiles to those currently complained about. Such an enquiry was available to the Board through investigating experts.
  2. [37]
    I accept the evidence of Mr Jenkins as to the good performance of some 8,000 similar designs on sites with similar characteristics.
  3. [38]
    I do not consider that I need to draw an inference that if footings and slabs are currently performing that they will continue to do so. I simply find that to the extent the Board has suggested through its witnesses that Mr Jenkins’ footings systems will not perform adequately over a 50 year life span, there is insufficient evidence to make any finding in this regard.

Has Mr Jenkins complied with AS2870?

Complaint

  1. [39]
    The Board asserts that Mr Jenkins has not complied with the AS2870-1996 Residential slabs and footings – construction. It says that he has not complied with the site investigation techniques set out in Clause 2.2 of the Standard to determine the site classification and underlying soil reactivity on each site.

The Standard

  1. [40]
    The Scope of the Standard is:

to set out the requirements for the classification of a site and the design and construction of a footing system for a single dwelling house, townhouse or the like… This Standard shall not be interpreted so as to prevent the use of materials or methods of design not referred to herein. Specifically, this Standard shall not be used to prevent the use of locally proven designs, or alternative designs in accordance with engineering principles.[3]

  1. [41]
    The Scope provision of the Standard notes that the Standard does not include design details for Class P sites.
  2. [42]
    Section 2 of the Standard refers to site classification into a number of classes. Relevant to these proceedings are:
  • Class S: Slightly reactive clay sites with only slight ground movement from moisture changes;
  • Class P: Sites which include soft soils, such as soft clay or silt or loose sands; landslip; mine subsidence; collapsing soils; soils subject to erosion; reactive sites subject to abnormal moisture conditions or sites which cannot be classified otherwise.
  • Class M: Moderately reactive clay or silt sites, which can experience moderate ground movement from moisture changes.
  • Class H: Highly reactive clay sites, which can experience high ground movement from moisture changes.
  • Class E: Extremely reactive sites, which can experience extreme ground movement from moisture changes.
  1. [43]
    Section 2 of the Standard provides:

2.1.1 Classification

Site classification is performed to allow the selection of standard footing designs presented in Section 3 or for the design of footing systems by engineering principles as described in Section 4.

Natural sites shall be classified into one of the classes given below in accordance with Clauses 2.2, 2.3 and 2.4 for both the expected extent of soil movement and the depth to which this movement extends.  In the classification, account shall be given to the possibility of a Class P site…

Note: Site classification may require consideration of factors beyond the boundaries of the subject site.

2.2.1 General

For sites that do not qualify as Class P sites, site classification shall include one or more of the following methods:

  1. (a)
    Identification of the soil profile and either-
    1. established data on the performance of houses on the soil profile; or
    2. interpretation of the current performance of existing buildings on the soil profile.
  2. (b)
    Estimation of the characteristic surface movement (Ys)

2.2.2 Identification of the soil profile

Identification of the soil profile and a classification from established data on the performance of houses on the soil profile are as follows:

  1. (a)
    The typical soil profile data given in Appendix D shall be used.  Where no data are provided in Appendix D, local knowledge where available shall be applied…
  2. (b)
    Identification of the soil profile and interpretation of the current performance of existing buildings.

Identification of the soil profile and interpretation of the current performance of existing buildings…which are not less than 10 years old and are founded on a similar soil profile shall be assessed in accordance with Table 2.2.

NOTE: The soil type and site conditions should be inspected at footing excavation stage by the classifier to confirm the soil profile.

2.2.3 Estimation of the characteristic surface movement

...The value of Ys shall be determined using soil shrinkage indices…

Soil shrinkage indices shall be derived using one or more of the following methods:

  1. (a)
    Laboratory tests for soil reactivity…
  2. (b)
    Correlations between shrinkage index (Ips) and other clay index tests for the soil type.
  3. (c)
    Visual-tactile identification of the soil by an engineer or engineering geologist having appropriate expertise and local experience…

2.3 Site Investigation Requirements

2.3.2 Purpose

The purpose of site investigation is to provide sufficient information to enable a site classification to be made, and to include information on the presence and depth of fill material, natural soil profile, and soil reactivity where required.

2.3.3 Depth of investigation

The soil profile shall be examined to a minimum depth equal to 0.75 times the depth of the suction change…but not less than 1.5m, unless rock is encountered or in the opinion of the classifier, further drilling is unnecessary for the purpose of identifying the soil profile in accordance with Clause 2.2.1(a).

2.3.4 Minimum number of exploration positions

For house sites, either of the following shall apply:

  1. (a)
    A minimum of one borehole or pit per house site…
  2. (b)
    A minimum of three boreholes per site in areas with deep-seated movements… and areas where the soil profile is known to be highly variable…

2.3.5 Assessment of allowable bearing pressure

Class A,S,M,H and E sites shall have adequate allowable bearing pressure…

Determination of allowable bearing pressure shall consider the weakest state of the foundation under normal site conditions; local knowledge shall be used…

2.4 ADDITIONAL CONSIDERATIONS FOR SITE CLASSIFICATION

2.4.4 Class P sites

Sites shall be classified as Class P if –

  1. (a)
    the allowable bearing pressure is less than specified in Clause 2.3.5;
  2. (b)
    excessive foundation settlement may occur due to the effects of fill loading on the foundation;
  3. (c)
    the sites contain uncontrolled fill or certain controlled clay fill as stipulated in Clause 2.4.6;
  4. (d)
    the sites are subject to mine subsidence, landslip, collapse activity or coastal erosion; or
  5. (e)
    the sites are subject to moisture changes due to extreme site conditions significantly more severe than the reasonable site conditions described in Clause 1.3.2.

3.1 SELECTION OF FOOTING SYSTEMS

3.1.1 Section procedure

Standard designs for footing systems shall be selected from Figures 3.1 to 3.6…These designs shall not apply to-

  1. (f)
    Class E or P sites…

Geotechnical investigations and site classification – Board’s position

  1. [44]
    The Board submits that Mr Jenkins is bound to determine underlying site reactivity to classify the site. It says that clause 2.2 of the Standard gives two methods for making this determination. 
  2. [45]
    In the report of Mr Davis, dated 14 January 2013, attachment PD – 16 to Exhibit 3 in the proceedings, Mr Davis says at paragraphs 24-28:
  1. The Standard requires that sites be classified in accordance with one of two prescribed methods, and footing systems be designed either by prescribing a standard (deemed to comply) design, or by adopting specific engineering design principles.
  2. In simple terms, site classification shall be by one or more of the following methods.
  1. Identification of the soil profile and either-
  1. established data on the performance of houses on the soil profile; or
  2. interpretation of the current performance of existing buildings on the soil profile.
  1. Estimation of the characteristic surface movement (Ys).
  1. Method (a) identification of the soil profile, requires the soil profile to be properly identified, and an assessment made of the in-service performance of lightly stiffened footings on the same soil profile in the region. In-service performance can then be benchmarked against certain criteria given in the Standard, to provide a site classification.
  2. Method (b) involves the estimation of characteristic surface movement by use of soil shrinkage indices appropriate to the soil profile of the site, and soil moisture change profile. This method requires appropriate site investigation, including laboratory testing. The parameters thus derived are different for different soils and cannot be estimated reliably by inspection or from correlation with other soil parameters.
  3. Method (b) is the more commonly adopted one, largely because there is rarely sufficient robust information on the in-service performance of existing footing systems.”

Methods used by Mr Jenkins to determine site classification and for site investigation

  1. [46]
    Mr Davis reports that Mr Jenkins has used his own method of site classification on all the sites in question, however he has also had access to results of site investigation by APOD Soil Testing Pty Ltd in relation to the Caithness and Carrigan sites. Perry Homes engaged APOD Soil Testing. APOD Soil Testing drilled boreholes, conducted a shrink-swell index test and provided a site classification for these sites. 
  2. [47]
    Mr Davis reports the method of site classification used by Mr Jenkins as:
  • site observations of the site itself and surrounding;
  • observations of cuttings where available near site;
  • hand probing where possible;
  • scala penetrometer testing;
  • examination of material through a magnifying glass.
  1. [48]
    Mr Davis reports that Mr Jenkins holds the view that, for most sites (including all 11 sites reviewed and reported on, the foundation soil is in a fully swelled (heaved) state and that the footing slab design does not need to take account of swell. He reports that Mr Jenkins holds the view that the footing slab will prevent significant moisture loss from the foundation soil beneath the footing slab, and hence the quantum of shrinkage the footing slab needs to cater for is relatively minor, commonly no more than 15mm shrinkage.
  2. [49]
    The evidence of Mr Jenkins is that he does use the methods attributed to him. Mr Jenkins methods are explained in detail in annexure “CJ7” to his affidavit sworn 21 May 2015, exhibit 8 in the proceedings. Annexure “CJ7” is a paper entitled “Engineering principles for residential slabs and footings” written by Mr Jenkins.  
  3. [50]
    Mr Jenkins’ evidence is that in addition to those methods, he assesses prior performance of constructions in the surrounding area and on similar profiles as observed by him in cuttings. He takes into account the matters in clause 1.3.3 of the Standard, being factors that give rise to abnormal moisture conditions. I note these are such matters as recent removal of large trees prior to construction, growth of trees too close to a footing and lack of maintenance of site drainage.
  4. [51]
    Mr Jenkins’ evidence is that until recently he has not used laboratory testing for reactivity. He assessed soil moisture content for relevancy and likelihood using the hand probe, by assessing existing proximity to plastic limits and assessing site geography.
  5. [52]
    He says that he does not remove samples but can observe them in cuttings or can assess a soil profile by hand probing and cone penetrometer testing. He says that cuttings can often be observed on neighbouring sites.
  6. [53]
    However, in order to determine the soil profile of black volcanic soil at Raceview which affected the Banksia, Brittany 35 and Brittany 43 sites, approximately 10 pier holes each were drilled on the sites to determine the geotechnical profile.
  7. [54]
    Mr Jenkins says that he has used these methods in respect of the vast majority of the 16,000 footings and slab designs prepared by him over a 50 year period. He prefers his methods in combination rather than soil content results or laboratory testing of results from subsurface drilling inspection and sampling to quantify reactivity, because those doing such testing often only use the most reactive layer, then carry out calculations that do not fit actual site profiles.
  8. [55]
    As to assessment of allowable bearing pressure Mr Jenkins says it is calculated by reference to the former Ordinance 70 of the Building Code of New South Wales.
  9. [56]
    Mr Jenkins confirms that for the Carrigan and Caithness sites he was provided with the results of an APOD Soil Testing Pty Ltd investigation, which he says he took account of. Nevertheless he is critical of what he notes as some shortcomings of the investigation which he addressed by his own testing.

Fox opinion of site classification methods

  1. [57]
    Mr Fox concluded that the approach to site classification adopted by Mr Jenkins, to use professional engineering concepts to obtain an engineering understanding of the site, is superior to the more conventional and simplistic reliance on soil testing. His evidence is that the approach to site classification adopted by Mr Jenkins is sound, but highly dependent on the personal experience, knowledge and skills of the engineer undertaking the work. Likewise, the approach by Mr Jenkins to assessment of foundation strength is said to be sound, when implemented by a suitably qualified and experienced practitioner.
  2. [58]
    Under cross-examination Mr Fox said that he infers from the case studies that Mr Jenkins has the appropriate skills.
  3. [59]
    Mr Fox makes the point that Mr Jenkins’ approach to site classification is very different to the technique of laboratory testing a soil sample taken at a specified minimum depth in accordance with the Standard. He says that Mr Jenkins approach is superior because it requires an engineering understanding of the site. Mr Fox’s evidence is that in most parts of Australia, a driller selects the sample location and technicians undertake site classification, with no input by an engineer. Further, the Standard does not require any assessment of the ground moisture state of the site at the time of classification and construction.
  4. [60]
    Mr Fox refers to two of Mr Jenkins key concerns in understanding the site, which he has drawn from Mr Jenkins paper, namely:
    1. (a)
      Identifying the starting moisture content of a site and the likelihood of moisture content changes and what those changes mean relevant to slab performance; and
    2. (b)
      Using a geological approach to understand the reactivity of foundation soils.
  5. [61]
    Mr Fox expresses the opinion that the main advantage of the geological approach, when compared to the numerical geotechnical approach, is that site geology is a much more robust indicator of soil properties than are soil tests. That is because the active zone on a residential site normally comprises one or two geological strata that might require identification whereas soil test results often vary dramatically depending on the exact composition of the particular soil sample extracted from the ground.
  6. [62]
    In relation to site investigation, Mr Fox notes that Mr Jenkins approach is aimed at answering two questions: what is the potential for ground movement due to soil reactivity, and is the ground strong enough to support the proposed residence? 
  7. [63]
    In relation to the first question, Mr Fox highlights the difference between Mr Jenkins’ approach and the approach of the Standard. He says that the Standard anticipates a site will potentially be subject to the full range of ground moisture change, that is – design wet to design dry, consistent with the climate in the area. The Standard assumes that proper site development and maintenance will prevent the occurrence of abnormal moisture conditions. Mr Jenkins assesses the in-situ moisture content of the clay on the site at or above the Plastic Limit. Mr Fox explained in evidence that Plastic Limit means how long before clay will crumble when rolled or in other words, how malleable it is. 
  8. [64]
    Mr Fox’s report, exhibit 5 in the proceedings sets out the theory that if the ground moisture present on a site when a slab is constructed is at or close to the design wet condition, there will be no or little heave of the site in the future, under normal conditions. Likewise, if the site is close to the design dry state, there will be no future settlement, as the ground will not dry out any further. It follows that in the former case there is no need to design for heave and in the latter case there is no need to design for settlement, as in both cases, the respective design states are redundant under normal moisture conditions.
  9. [65]
    Mr Fox notes that Mr Jenkins’ relevant design for footings and slabs is based on the in-situ moisture content of the clay, being at or above Plastic Limit or less than the Plastic Limit. The design is intended to ensure that differential movement of the ground should not exceed 15mm, consistent with Class S in accordance with the Standard.
  10. [66]
    Mr Fox was not critical of this approach in his report or in cross- examination.
  11. [67]
    Finally, Mr Fox commented favourably on the use by Mr Jenkins of a magnifying glass as a way of looking for “flocculating clays” and his inspection of sites for signs of abnormal moisture conditions or other noteworthy features.
  12. [68]
    Mr Fox concluded that Mr Jenkins’ approach to site classification is sound, but highly dependent on the personal experience, knowledge and skills of the engineer undertaking the work.
  13. [69]
    In relation to Mr Jenkins determination of ground strength, Mr Fox described the following methods:
    1. (a)
      Ensuring any filling is “controlled filling” and requiring each pier to be inspect by a supervisor during construction to ensure that suitable “firm” material has been reached.
    2. (b)
      Use of a Scala penetrometer to assess the in-situ strength of the foundation.
    3. (c)
      Use of a probe (a steel rod 1,5 m long and 10mm diameter, with a “T” handle at the top)  to penetrate the ground, on a grid of nominal 2,5 m each way to assess the consistency of the foundation.
  14. [70]
    Mr Fox concluded the approach by Mr Jenkins to assessment of foundation strength is sound when implemented by a suitably qualified and experienced practitioner.

Board’s complaint as to the result of Mr Jenkins site classification and investigation methods

  1. [71]
    Mr Davis is critical of Mr Jenkins methods. He says that they do not accord with modern practice as promulgated by the Standard.
  2. [72]
    The Board submits that Mr Jenkins:
    1. (a)
      Does not use an estimation of the characteristic surface movement (Ys);
    2. (b)
      Does not say where cuttings are and when they were observed in relation to identification of soil profile. There can be no confidence as to the soil profile of a particular site by reference to cuttings in the vicinity;
    3. (c)
      When referencing the performance of houses in the area cannot say that the soil profile is the same for a comparator site as for the site in question.
  3. [73]
    The Board submits that Mr Jenkins use of a penetrometer, listening and magnifying glass techniques and starting moisture content assessment do not determine soil profile or reactivity in accordance with the Standard.
  4. [74]
    The Board asserts that Mr Jenkins has classified the sites in question as “S”, but others have classified them as higher. It is said that none of his methods allow him to properly determine soil reactivity and that however one looks at it there has been no proper analysis, which is an essential input to the footing design.
  5. [75]
    Mr Davis complains that the result of Mr Jenkins methodology is:
    1. (a)
      In 9 of the 11 sites the subject of the report, Mr Jenkins gives a Class “S” site classification, based on the premise that the foundation soils were at sufficiently high moisture content that foundation swell would not occur over the life of the structure and that foundation shrinkage would not exceed 15 mm. There is said to be no sound technical justification for this assessment and further it is substantially different to the more rigorous practice espoused by AS2870.
    2. (b)
      The site classifications ignore the effects of trees that are, or were, at or in close proximity to the building site.
    3. (c)
      The site classifications ignore Mr Jenkins own notes about tree stump holes or uncontrolled fill that warrant the site being classified as “P”.
    4. (d)
      Mr Jenkins had little or no site-specific information about the moisture content or the threshold limit at which no more foundation swelling would take place. Further, his assessment ignores the fact that, over the life of the structure, foundation moisture content can reduce as a result of seasonal drying effects, and result in shrinkage.
  6. [76]
    Mr Davis concludes that the methodology used by Mr Jenkins for classifying sites is ill-founded and has resulted in the sites being under-classified. Under classification results in the design of footing slabs that do not have the structural rigidity to withstand swell-shrink effects that may result from seasonal changes in soil moisture content. Without appropriate structural rigidity, footing slabs and the buildings supported thereon may crack.
  7. [77]
    Mr Davis was asked by the Board to conduct his own site classifications and to provide an opinion on the footing and slab designs prepared by Mr Jenkins for dwellings constructed at the Neptune, Greenway, Shergar, Amadeus, Killarney, Zahnows and Carrigan sites. His findings are set out in a supplementary report, dated 9 April 2015, exhibit 4 in the proceedings.
  8. [78]
    At this point, I will deal only with the question of site classification. Mr Davis concluded, as a result of laboratory tests to determine characteristic surface movements (Ys), that each site had the following classification:
    1. (a)
      Neptune: Class “H” (borderline Class “E”). He asserts that Mr Jenkins classified the site as Class “S” and ignored the effect that trees were likely to have on foundation movement.
    2. (b)
      Greenway: Class “P”. He asserts that Mr Jenkins classified the site as Class “S”.
    3. (c)
      Shergar: Class “E”. He asserts that Mr Jenkins classified the site as Class “S” and ignored the effect that trees were likely to have on foundation movement.
    4. (d)
      Amadeus: Class “H”. He asserts that Mr Jenkins classified the site as Class “S” and ignored the effect that trees were likely to have on foundation movement.
    5. (e)
      Killarney: Class “M”. He asserts that Mr Jenkins classified the site as Class “S” and that he ignored the presence of major tree stump holes.
    6. (f)
      Zahnows: Class “P” with a footing slab to be designed for Class “M”. He asserts that Mr Jenkins classified the site as Class “S”.
    7. (g)
      Carrigan: Class “H”. He asserts that Mr Jenkins classified the site as Class “S” and ignored the effect that a tree close to the building footprint was likely to have on foundation movement.

Jenkins’ response

  1. [79]
    Mr Jenkins’ evidence is that the sites are all Class “P” and that is shown on his investigation reports for each site, together with the reason for that classification. Mr Fox confirmed in evidence that the reports disclose the Classification as “P”. Mr Davis’ evidence is that he found the reports confusing.
  2. [80]
    I note Mr Jenkins practice in each report was to use an “XX” key and to then record the Classification. I find that the reports for each site disclose the Classification as “P”.
  3. [81]
    On the basis of this evidence I find that Mr Jenkins did classify the sites as “P”.

Comparison of different approaches

  1. [82]
    The evidence of Mr Fox and Mr Jenkins is that the “P” classification is different to estimated ground movement for which footings and slabs are designed by Mr Jenkins. In each case Mr Jenkins assessed the expected ground movement under the slab due to soil moisture changes. In the absence of abnormal moisture conditions, he estimated that would be 15mm, which was equivalent to Class S in accordance with the Standard. Mr Jenkins’ evidence is that is not a site classification of “S”.
  2. [83]
    Mr Davis has not made reference in his report to the characteristics of the sites which suggest a classification of “P”. He agreed in evidence that if the site is classified as “P” the Standard does not apply in terms of the methods it prescribes, however, it is still necessary for the slab designer to determine the reactivity of the site to specify the footings and slab.
  3. [84]
    Mr Davis and Mr Jenkins have undertaken different methods to determine the type of footings and slab appropriate to the site. Mr Fox cautions against a comparison of the Jenkins estimates of ground movement and the estimated Ys for the site undertaken by Mr Davis and earlier geotechnicians. As discussed earlier he points out that the respective derivations were based on different assumptions regarding expected ground moisture changes over the design life of the residence.
  4. [85]
    Mr Davis acknowledged the different methodology as an explanation for the assertion at paragraph 32AD of the Further Amended Application, that the site classification by Mr Jenkins, shows potential vertical movement less than if the site was classified in accordance with AS2870.
  5. [86]
    During cross-examination Mr Jenkins said that Mr Davis varied in his report from what he told him about the site classes being Class “P”. He explained what he meant by the reference in his reports to Class “S”. He said he told Mr Davis that provided the “P” classification is addressed and trees are kept away, the house slab will behave as per a Class “S” site.
  6. [87]
    It was not suggested to Mr Jenkins in cross-examination that the conditions which give rise to a Class “P” site were not present on all the sites, or that the sites were not in fact Class “P” sites. It was not put to Mr Jenkins in cross-examination that he had classified the sites as “S”.
  7. [88]
    Mr Davis has not asserted that the sites in question are not properly characterized as Class “P” sites, despite his own site classification. I note from the evidence of both Mr Fox and Mr Davis that it is possible for a site to be both a Class “P” site and another Class.
  8. [89]
    I find that not only has Mr Jenkins classified the sites as “P”, they are in fact properly classified as “P”.
  9. [90]
    In cross-examination, Mr Davis agreed that the Neptune site was characterized correctly as Class “P” because of the tree stump holes on the site. Mr Davis agreed that because of that classification his complaint falls away, that Mr Jenkins investigation does not allow for a proper determination and characterisation of the ground conditions at site, as asserted in paragraph 32AB(a) of the Further Amended Application
  10. [91]
    In cross-examination Mr Davis agreed that if a site is properly characterized as Class “P” then it cannot be contended that the site classification methodology adopted by Mr Jenkins is not in accordance with accepted industry practice and is not supported by AS2870, as asserted in paragraph 32AC of the Further Amended Application.
  11. [92]
    Mr Davis was reluctant to accept Mr Jenkins method of estimating ground movement. He expressed a clear preference for drilling and laboratory testing as a means of determining estimated ground movement. He said that he does not think it is adequate to assess estimated ground movement by just looking at the site or picking up soil and feeling it. He said that an assessment of vertical movement is needed. Mr Davis did acknowledge in cross-examination that the Ys method is not mandatory and that there are  other methods referred to in the Standard. He acknowledged that he has not in his reports discussed in detail the other means of testing anticipated by the Standard, and has not addressed, in this context the work done by Mr Jenkins. These concessions were made in response to questions in cross-examination about the assertion in paragraph 32AB of the Further Amended Application, that none of the steps taken by Mr Jenkins are capable of quantifying the reactivity of the foundation soil which are crucial factors in the design of footing slabs.

Findings

  1. [93]
    I find that all sites were Class “P”. I find that is how Mr Jenkins classified the sites and that he did not classify the sites as Class “S”. I find that it is misguided for Mr Davis to attempt to compare the site classification he assessed by use of Ys testing and calculations, to a classification wrongly assumed to have been made by Mr Jenkins.
  2. [94]
    I find that what follows from all the sites in question being Class “P” is that Mr Jenkins is not bound to use the methods referred to in clause 2.2 of the Standard for site classification. Because of the “P” classification of the sites, and the express exclusion of Class “P” sites from clause 2.2 of the Standard, I find that the Standard permits other methods of site classification.
  3. [95]
    I accept Mr Jenkins’ evidence as to his site investigation methods and find that despite not being compelled to follow the Standard, Mr Jenkins has utilized the methods in clause 2.2.1(a)(i) and (ii) of the Standard and in particular has utilized his local knowledge for the purpose of identifying soil profile. I accept the evidence of Mr Jenkins as to his use of observation of cuttings and performance of houses in the area. These are methods available to be used as an alternative to an estimation of the characteristics of surface movement (Ys).
  4. [96]
    Given Mr Jenkins long experience and qualifications together with the history of good performance of his footing systems, I find that he is suitably qualified to use the site investigation methods employed by him and on this basis I accept the evidence of Mr Fox that all the site investigation methods used by Mr Jenkins are sound.
  5. [97]
    Mr Jenkins agrees that in order to properly design a footing system for the site, he must assess the reactivity of the foundation soil. I find that Mr Jenkins did not “quantify” the reactivity of the foundation soil. Instead, he relied on an assessment of the moisture state relative to Plastic Limit. Because of the “P” classification of the site he was not obliged to undertake a Ys determination.
  6. [98]
    I find that as noted by Mr Fox this is a different method to that set out in the Standard and gives different outcomes, so that a proper comparison of results is not possible. To the extent that Mr Davis has attempted such a comparison, his conclusions are unreliable. Mr Fox was not critical of the method and expressed the opinion that it was sound. I accept his expert opinion and reject the opinion of Mr Davis in this regard. I do so on the basis of Mr Fox’s superior experience in residential footing systems.

Are the footing systems designed by Mr Jenkins inadequate for the sites on which they were constructed?

  1. [99]
    This is a question which goes to performance and the appropriate design response to a determination of site classification and soil reactivity.
  2. [100]
    Mr Davis agreed in cross-examination that in his analysis of the sites he ignored any “P” classification. He relied on a determination of site reactivity achieved through laboratory analysis and shrink/swell calculations. He then applied the slab design prescribed by the Standard for a site with that classification. 
  3. [101]
    Mr Jenkins on the other hand used the “P” classification to drive the design response. Because of that classification the Standard provides that reference should not be made to any standard design.
  4. [102]
    Mr Davis has proceeded on a misapprehension that Mr Jenkins has underclassifed the sites as Class “S” and has designed footings and slabs as if the site were Class “S” so as to result in inadequate footings and slabs given the much more reactive sites. He undertakes a comparison of the slabs with the slabs prescribed by the Standard to demonstrate inadequacy. He concludes that the slabs designed by Mr Jenkins are not as stiff as required by AS2870 for its standard designs for Class “H” and “M” sites, but are similar to the stiffness required by the Standard’s deemed to comply designs for a Class “S” site.
  5. [103]
    A difficulty for the Board is that Mr Davis acknowledged in cross-examination that he did not have the expertise or qualifications to express an opinion on the matter of design. He admitted that he rarely designs for house sites and that he has no experience in residential footings and slabs. He felt able to undertake a comparison of Mr Jenkins designs with the deemed to comply designs in the Standard and to conclude that Mr Jenkins did not use the deemed to comply designs.
  6. [104]
    Mr Davis said that he would prefer not to give an opinion on design issues and that his comments in relation to design issues could be ignored in these proceedings.
  7. [105]
    Mr Jenkin’s counsel informed the Tribunal that as inadequacy of design was one of three issues raised against Mr Jenkins, he would modify his questions to take account of Mr Davis’ concession. Likewise counsel for the Board did not pursue questions of design in cross-examination of Mr Fox, but did pursue questions of performance of the footings and slabs.
  8. [106]
    Mr Fox described Mr Jenkins’ design philosophy as use of piers in areas of uncertain strength and an expectation that heave and settlement of the slab would be slight due to the moisture content of the ground (or site modification to that effect) remaining stable once sealed by the slab. Accordingly, there was no need for slab stiffening.
  9. [107]
    The slab designs typically include slab key joints to prevent or limit shrinkage and cracking. He commented that AS2870 proscribed the use of permanent joints in the deemed to comply standard designs, however, the Standard allowed the use of joints where the engineer specified them.
  10. [108]
    Mr Fox expressed the opinion that the standard slab system design adopted by Mr Jenkins is sound when integrated with his site investigation approach. I accept that opinion.
  11. [109]
    Mr Jenkins’ evidence is that provided the “P” classification is addressed and trees are kept away, a house built on a slab designed by him will behave as if it were a Class “S” site. He said that AS2870 allows for a pier and flat slab and that is what he designs. He said that he did not agree the stiffness in his slabs that of a deemed to comply slab for a Class “S” site and not for a Class “H” or “M” site. Mr Jenkin’s evidence is that his slabs are stiff for a span of 2.5 metres and that it is a matter of structural design.
  12. [110]
    Mr Jenkins’ evidence is that his designs have been used on 8,000 other sites with no complaint. Where an issue has been raised he has investigated and usually found a problem of lack of maintenance such as water ponding against the house, which has been rectified. I accept this evidence. No evidence was put to the contrary.

Findings

  1. [111]
    I find on the basis of Mr Jenkin’s evidence that the footing systems designed by him are performing and that the designs are an appropriate response to the site classification and estimated moisture change at the site.
  2. [112]
    I reject any opinions expressed by Mr Davis in relation to the appropriateness of the footings design for the sites in question, on the basis of his acknowledged lack of expertise.
  3. [113]
    On the basis of Mr Fox’s expertise, I accept his opinion that the footing system designs are sound and are performing.

Are Mr Jenkins’ site investigation reports inadequate or misleading?

  1. [114]
    The Board complains that Mr Jenkins’ reports are likely to mislead a local authority to whom the report is addressed, because:
    1. (a)
      The reports suggest compliance with AS2870, particularly that a determination of Ys has been carried out, because Table 2.3 of the Standard has been reproduced in the reports.
    2. (b)
      The report suggests that boreholes have been dug to reveal the soil profile, when that is not the case.
    3. (c)
      The means by which Mr Jenkins arrived at site classifications and allowable bearing pressure are not set out in detail. In particular no detail is given as to how a comparison with other houses on a similar soil profile has been done, where the other houses were located or what was observed. It is said that Mr Jenkins’s site classification cannot have been derived in accordance with AS2870.
  2. [115]
    Mr Fox expresses the opinion that the reports were principally intended for use by Mr Jenkins and any uncertainty or ambiguity in the reports in the hands of readers not familiar with the style of the report is met by the clear disclaimer in upper case appearing above the signature block:

THIS REPORT, PARTICULARLY SITE CLASSIFICATION IS FOR COL JENKINS & ASSOCIATES TO USE IN DESIGN. ANY DESIGN BY ANYONE ELSE FOR ANY STRUCTURE MUST BE SPECIALLY APPROVED BY COL JENKINS & ASSOCIATES.

  1. [116]
    Mr Fox refers to use of a site reactivity table and notes that it is used to signify “Slight” site reactivity (notwithstanding the possible reactivity as would for example be measured in the laboratory), either due to the existing moisture conditions on the site or through site modification.
  2. [117]
    In relation to Class “P” site conditions, Mr Fox notes the use of an “XX” symbol to advise of such conditions and the reason for the classification. For example: “Class ‘P’ Cut to fill and tree stump holes”. He also refers to the use of notes to include site classification-related advice, for example in relation to possible tree effects.
  3. [118]
    Mr Fox concluded that the report format adopted by Mr Jenkins is acceptable for the limited application for which it is intended. I accept that opinion, based on Mr Fox’s expertise in residential construction.
  4. [119]
    In cross-examination Mr Fox said that in his experience in practice a site investigation report is used by local government to confirm that a site investigation has been done, however its contents are not reviewed. He said that there is no statutory basis for a local government to require a report which confirms that the Standard has been complied with in the site investigation. He said that a greater role has been given to certifiers and that the local authority merely keeps the record. I accept this evidence.
  5. [120]
    No evidence was called from any local authority to give evidence as to the use made of the investigation report. No evidence was called from any local authority to the effect that it had been misled or confused by Mr Jenkins’ site investigation reports.
  6. [121]
    Mr Davis confirmed in cross-examination that there was no evidence of   complaint by any local authority in this case. He also said that Mr Jenkins had explained to him what the Table in the report and the reference to moisture change meant and that he considered what was set out in the report to be acceptable. Mr Davis said that as long as the report is to be used by Mr Jenkins, then there is no issue of peer review. He also confirmed in relation to the reporting practices of Mr Jenkins’ peers that if the investigation undertaken by Mr Jenkins was open to him under the Standard, then the report is in order.
  7. [122]
    Mr Davis confirmed in cross-examination that the reports were clear no boreholes had been drilled and that this complaint should be ignored.
  8. [123]
    Mr Jenkins’ evidence confirms that the site investigation reports are prepared for himself and are designed to give him enough information to design with confidence. He said that he complies with AS1726-1993, Australian Standard Geotechnical site investigations in relation to his site investigations and the form and content of his reports. That Standard appears at annexure 8 to the Mr Jenkins affidavit, Exhibit 8 in the proceedings.

Finding

  1. [124]
    I find that the site reports in question record Mr Jenkins investigations and methods which are conducted in a way permitted by AS2870. I find that the reports comply with AS1726-1993. I find that the reports are used for Mr Jenkins’ own design purposes and that the question of misrepresentation or confusion to peers or a local authority does not arise.

Have the grounds for disciplinary proceedings taken against Mr Jenkins been established

  1. [125]
    Mr Jenkins provided me with a table of responses to allegations against him, as part of his final submissions. The table has the advantage of setting out each allegation made against Mr Jenkins and noting the site or sites to which it applies. The table notes certain concessions made by Mr Davis and records abandonment of certain allegations. Counsel for the Board submitted that the concessions made by Mr Davis are not as broad as contended and that it is not for Mr Davis to abandon allegations. Counsel submitted that it is a matter for the Tribunal to determine whether the allegation is established by the evidence. Nevertheless no submissions were made which addressed the evidence in relation to each of the grounds set out in some 50 pages of allegations and amended allegations. Instead the submissions in this matter rolled up the allegations as summarised by me early in this decision.
  2. [126]
    I have made findings already with respect to many of the Board’s complaints. For completeness, I will traverse the allegations as set out in the table of responses, which I consider a fair compilation of the allegations in the Further Amended Application.
  3. [127]
    Allegation at paragraph 31(a): in providing the geotech report, Mr Jenkins provides a site classification and allowable bearing pressure but is silent on how these design parameters are derived. I find that the information contained in the report is for Mr Jenkins use in designing the footings and slabs. Mr Jenkins knows what steps he took to derive those design parameters. In these circumstances, the complaint is not made out as evidence of unsatisfactory professional conduct.
  4. [128]
    Allegation at paragraph 31(b) and 37 (e): the report identifies the influence of trees, but fails to assess a site classification that recognises the influence of trees on foundation movement. On its face the report appears to rate the site as Class S, rather than at least a Class M to take account of the influence of trees in the vicinity. I find that the site was classified as “P”, which recognises the influence of trees on foundation movement. Further, Class M is referenced on the face of the report and notes are made about the influence of trees where relevant. The complaint is not made out as evidence of unsatisfactory professional conduct.
  5. [129]
    Allegation at paragraphs 31(c), 37(c), 43(d), 49(b), 56(d), 62(c), 67(a), 72(c), 77(c), 82(d) and 87(d): the geotechnical report states that the investigation is carried out to AS1726 and AS2870, when it does not follow either of the two methods adopted in AS2870 being:
    1. (i)
      identification of a soil profile that has been correlated with the performance of houses provided with lightly stiffened strip footings or slabs on ground; and
    2. (ii)
      estimation of characteristic movement (Ys) by calculation.

I find on the basis of the evidence discussed earlier in this decision that the sites in question were classified “P” and that Mr Jenkins followed a methodology permitted by AS2870. I find that his reports are consistent with AS1726. The complaint is not made out as evidence of unsatisfactory professional conduct.

  1. [130]
    Allegation at paragraphs 31(d), 37(d), 43(e), 49(h), 56(e), 62(d), 67(b), 72(d), 77(d), 82(e) and 87(e): In preparing the geotechnical report Mr Jenkins uses a method of site classification that is not conducive to a reliable assessment of shrink swell potential.  The method:
    1. (a)
      does not rely on soil moisture content results or lab testing for reactivity;
    2. (b)
      no subsurface drilling inspection and sampling;
    3. (c)
      relies on qualitative assessment;
    4. (d)
      does not allow for quantification of reactivity and does not provide a basis for calibrating judgments about reactivity.

I find that that Mr Jenkins has classified the sites as “P”. Thereafter for the purpose of determining site reactivity he adopts a method estimated moisture change, which is different to an assessment of shrink swell potential, as set out in AS2870. I find that he is entitled to adopt a different method and that based on the evidence set out earlier in this decision, it is a sound method of proceeding. The complaint is not made out as evidence of unsatisfactory professional conduct.

  1. [131]
    Allegation at paragraphs 32(a), 38(a), 44(a), 50(a), 57(a), 63(a), 73(a), 78(a), and 83(a): The geotechnical report provides no logical or engineering derived methodology to substantiate either the site classification or the allowable bearing pressure. I find that the report is for Mr Jenkins use as designer. I find that he is not obliged by any Australian Standard to substantiate in the report the site classification or allowable bearing pressure. The complaint is not made out as evidence of unsatisfactory professional conduct.
  2. [132]
    Allegation at paragraphs 32AA, 38AA, 44AA, 50AA, 57AA, 63A, 73A, 78AA, 83AA, and 88A: The geotechnical report is below industry standards set out in AS1726 and AS2870. There is no evidence of a report conforming to industry standards before the Tribunal. When questioned about this issue, Mr Davis referred to reports done by Cardno Bowler which are attached to his report. Mr Davis confirmed that the reports were commissioned to assist in his investigation however the instructions for the reports were not in evidence. I find that there is no evidence of an industry standard report which I am able to compare to the reports of Mr Jenkins.
  3. [133]
    In relation to the particulars given as to how the reports fall below industry standards, it is asserted in paragraphs 32AA(a), 38AA(a), 44AA(a), 50AA(a), 57AA(a), 63A(a), 68A(a), 73A(a), 76AA(a), 83AA(a) and 88A(a) that it is not clear what investigation was carried out. I find again, that as the report is prepared for use by Mr Jenkins as designer, this is not a reasonable criticism. The criticism was not maintained by Mr Davis under cross-examination.
  4. [134]
    It is asserted in paragraphs 32AA(b), 38AA(b), 48AA(b), 50AA(b), 57AA(b) and 78AA(b) that the reports imply investigation holes and testing pits were dug at site though this may not have been the case. Mr Davis said in cross-examination that the reports were clear that no holes had been drilled and that this complaint should be ignored.
  5. [135]
    It is asserted in paragraphs 32AA(c), 38AA(c), 44AA(c), 50AA(c), 57AA(c), 63A(c), 68A(b), 73(b), 78AA(c) and 83AA(b) that the reports are ambiguous in the presentation of penetrometer results. Mr Davis acknowledged that the reports do express the rate of penetration into the soil of the pentrometer when a blow is applied. The rate is expressed as 00-1500mm, maximum 25mm per blow.
  6. [136]
    It is asserted in paragraphs 32AA(d), 38AA(d), 44AA(d), 50AA(d), 57AA(d), 63A(d), 63A(c), 68A(b), 73A(c), 78AA(d) and 83AA(c) that the reports are ambiguous in the presentation of the site classification. I find again that the reports clearly show the classification “P” and that is evident from the key used – “XX”. It is again relevant that the report is for Mr Jenkins use as designer and any ambiguity is of little relevance.
  7. [137]
    As to the assertions in paragraphs 32AA(e), (f), (g) and (h); 38AA(e), (f), (g) and (h); 44AA(e), (f), (g) and (h); 50AA(e), (f), (g) and (h); 57A(e), (f), (g) and (h); 63A(d), (e), (f) and (g); 68A(c), (d), (e) and (f); 73A(d), (e), (f) and (g); 78AA(e), (f), (g) and (h); 83AA(d), (e), (f), (g); and 88A(c), (d), (e) and (f), Mr Davis agreed in cross examination that he did not know what was meant by the assertions. The assertions are that the reports do not provide a clear record of the engineering characteristics of the site, provide little basis for footing slab design by other than the respondent, imply incorrectly that local authority processes have been undertaken and imply incorrectly that more detailed work was undertaken by Mr Jenkins than in fact has been undertaken. There is no evidence to support the assertions, even if they were able to be understood.
  8. [138]
    It is asserted in paragraphs 32AA(i), 38AA(i), 44AA(i), 50AA(i), 57AA(i) and 78AA(i) that the reports are prepared without holes being drilled to verify the soil profile while still relying on the soil profile for a footing slab design. For the reasons set out earlier in this decision I find that the methods of site investigation used by Mr Jenkins to determine soil profile are acceptable methods and available to him pursuant to AS2870.
  9. [139]
    It is asserted at paragraphs 32AA(j) and (k), 38AA(j) and (k), 44AA(j) and (k), 50AA(j) and (k), 57AA(j) and (k), 63A(h) and (i), 68A(g) and (h), 73A(h) and (i), 78AA(j) and (k), 83AA(h) and (i) and 88A(g) and (h) that the reports are not suitable for peer review and do not meet reporting practices commonly adopted by peers. These assertions have been made earlier. I again find that there is no question of peer review of the reports as they have been prepared for use by Mr Jenkins as the designer. Again, I find that there is no evidence of a standard report from Mr Jenkins peers and that as the methods adopted by him are available under AS2870, the results of his investigations recorded in the reports are acceptable.
  10. [140]
    I find that the complaints as to the geotechnical reports are not made out as evidence of unsatisfactory professional conduct.
  11. [141]
    Allegation at paragraphs 32AB, 38AB, 44AB, 50AB, 57AB, 63B, 68B, 73B, 78AB, 83AB and 88B: That the scope of the geotechnical investigation is of a lesser standard than expected by peers as:
    1. (a)
      It does not allow for the proper determination and characterisation of the ground conditions at site. It was put to Mr Davis in cross-examination that if in the case of the Neptune site, it has been characterised correctly as “P” because of tree stumps and noting that Cardno Bowler had classified it as a “P” site, then the complaint falls away. Mr Davis agreed. On the basis of Mr Davis’ evidence and the evidence of Mr Fox referred to earlier in this decision, I find that Mr Jenkins’ geotechnical investigation does allow for the proper determination and characterisation of the ground conditions at site.
    2. (b)
      None of the steps taken by Mr Jenkins are capable of quantifying the reactivity of the foundation soil which are crucial factors in the design of footing slabs. In cross-examination Mr Davis agreed that the Standard accommodates other methods of determining soil reactivity than laboratory tests. Mr Jenkins does not purport to quantify the reactivity of the foundation soil. He is not obliged to do so under the Standard, because of the “P” classification of the site. He adopts a different method directed to estimated moisture change. On the basis of the expert evidence of Mr Fox, I have found that this method is acceptable in terms of the Standard and for the purpose of designing a footing system for the particular site.

I find that the complaint is not made out as evidence of unsatisfactory professional conduct by Mr Jenkins.

  1. [142]
    Allegation at paragraphs 32AC, 38AC, 44AC, 50AC, 57AC, 63C, 68C, 73C, 78AC, 83AC and 88C: that the site classification methodology is not in accordance with accepted industry practice and is not supported by AS2870. In cross-examination Mr Davis agreed that this allegation cannot be sustained if it is the case that the sites in question have been correctly classified as “P”. On the basis of the finding as to the classification of the sites as “P” I find that this complaint is not made out as evidence of unsatisfactory professional conduct.
  2. [143]
    Allegation at paragraphs 32AD, 38AD, 44AD, 50AD, 57Ad, 63D, 68D, 73D, 78AD, 83AD and 88AD: that the site classification shows vertical movement less than if the site was classified in accordance with AS2870. In cross-examination Mr Davis agreed that the measure adopted by Mr Jenkins reflects a different methodology to that adopted by him. I find that this complaint is not made out as evidence of unsatisfactory professional conduct.
  3. [144]
    Allegation at paragraphs 32A(a), 44A(a), 50A(b), 57A(a), 78A(b) and 83A(b): that Mr Jenkins failed to design footing for a P/H site of which Neptune/Amadeus was one; for an H site of which Shergar/Zahnows was one; for an M site of which Killarney was one and for a P/H2 site of which Carrigan was one. In the joint expert report, Mr Fox and Mr Davis addressed the allegation at paragraph 32A(a) in relation to the Neptune site, however, they agreed that the analysis in relation to that site was representative of their views in regard to the other grounds having regard to the individual characteristics of the sites in question.
  4. [145]
    In the joint report Mr Davis confirmed his own report, which is reflected in the allegation. Mr Fox said that the class P aspects of the site were addressed by the specification of piers, and Mr Jenkins allowed for the potential highly reactive movement by considering the restricted range of ground moisture change for which his design was intended. I prefer the evidence of Mr Fox and find that the complaint is not made out as evidence of unsatisfactory professional conduct by Mr Jenkins. I do so on the basis of Mr Fox’s superior expertise in residential footings and slabs.
  5. [146]
    Allegation at paragraphs 32A(b) and 44A(b): that Mr Jenkins designed a footing system with inadequate stiffness to cater for a typical class H site under conditions of good site drainage and maintenance. In the joint experts report, Mr Davis confirmed his own report which reflects the allegation. Mr Fox said that adequate stiffness was provided to cater for the expected ground movement on the subject site at the time of design. I prefer the evidence of Mr Fox and find that the complaint is not made out as evidence of unsatisfactory professional conduct. I do so on the basis of Mr Fox’s superior expertise in residential footings and slabs.
  6. [147]
    Allegation at paragraph 32A(c): that Mr Jenkins did not make allowance for potential differential movement caused by abnormal conditions including trees and poor drainage. In the expert report, Mr Fox and Mr Davis agree that there was no need to design for poor drainage at the northern end of the dwelling. Mr Davis believes the design should have allowed for the presence of trees. Mr Fox says that at the time it was not normal to design having regard to existing trees and AS2870 contained no provision for such design. I prefer the evidence of Mr Fox and find that the complaint is not made out as evidence of unsatisfactory professional conduct. I do so on the basis of Mr Fox’s superior knowledge of AS2870.
  7. [148]
    Allegation at paragraph 32A(d): that Mr Jenkins designed a footing system below the required minimum strength when compared to AS2870. In the joint experts’ report Mr Davis confirmed his own report which reflects the allegation. In cross-examination he explained that he was comparing Mr Jenkins design with features of the design for an “H” classified site set out in the “deemed to comply” designs in the Standard. He considered there was a great difference between the two. Mr Fox said that it was not necessary to provide that strength, based on the particular slab design. He said in cross-examination that a 385 deep waffle raft was the deemed to comply Standard for an H site. He commented that the 385 deep waffle raft would still have resulted in undulations in the slab. Mr Fox said that Mr Davis proposed the use of a 500 deep waffle raft to result in less damage. Mr Fox’s evidence was that such a footing system would be very expensive and the only one used in Australia. I prefer the evidence of Mr Fox on the basis of his superior expertise in residential footing and slabs and find that the complaint is not made out as evidence of unprofessional conduct.
  8. [149]
    Allegation at paragraph 32A(e), 38A(e), 44A(e): that Mr Jenkins failed to take into account trees as required by AS2870. In the joint experts’ report Mr Davis confirmed his own report which reflects the allegation. Mr Fox said that Mr Jenkins did take trees into account in terms of the need for treatment of holes left by the removal of trees at the Neptune site. He said that AS2870 at the time had no provision for design for existing trees, and it was not common practice for engineers to design for trees at the time. I prefer the evidence of Mr Fox on the basis of his superior expertise in AS2870 and in residential footings and slabs. I find that the complaint is not made out as evidence of unsatisfactory professional conduct.
  9. [150]
    Allegations at paragraphs 37(a), (b), (c) and (d); 43(b) and (c), 56(b) and (c), 62(a) and (b), 72(a) and (b), 77(a) and (b), 82(b) and (c) and 87(c).  These allegations repeat complaints dealt with in earlier paragraphs. I do not propose to deal further with them, except insofar as it is alleged, as a new particular, that Mr Jenkins failed to have regard to APOD investigations. I find that he did have regard to APOD investigations and that Mr Davis acknowledged this fact in cross-examination. The complaints are not made out as evidence of unsatisfactory professional conduct.
  10. [151]
    Allegation at paragraph 38A(a): that Mr Jenkins designed a footing system for a level 1 controlled compaction site without proper reference to any level 1 compaction certificate, when the Greenway Site fill should have been classed as “uncontrolled”. Mr Davis conceded in cross-examination that he was mistaken, that there is a compaction certificate and that the complaint is no longer relevant. Accordingly, I find that there is no evidence of unsatisfactory conduct.
  11. [152]
    Allegations at paragraphs 38A(b),(c),(d); 50A(c); 83A((a); 44A(c); 50A(a); 57A(b); 78A(a),(c); 83A(c); 83A(d),(e) and (f)), which raise criticisms of – the use of joints, the requirements for footing piers and depth of footing piers; stiffness of the footing system; underestimation of potential ground surface movements at a Z site in the design; adequacy of the footing system for soil conditions; inadequate stiffness to reduce curvature and deformation; a design which exacerbated the effect of any reactive clay soil movement and a design not performing in accordance with normal expectations. These are design issues. Mr Davis said in cross-examination that he had no experience in the design of residential footings and slabs and that he would prefer not to express an opinion on design issues. He agreed that all his comments on design in his reports can be ignored. In relation to the performance complaint at paragraph 44A(c) Mr Davis agreed in cross-examination that the cracking at the Shergar site is category 1 and 2 and therefore it is performing after 11 years.
  12. [153]
    Accordingly, I find that the complaints are not made out as evidence of unsatisfactory professional conduct. This is so, particularly, in light of the evidence of Mr Fox that the standard slab system design adopted by Mr Jenkins is sound when integrated with Mr Jenkins’ site investigation approach. I accept the evidence of Mr Fox on the basis of his expertise in residential footing systems.
  13. [154]
    Allegation at paragraph 43(a): that Mr Jenkins in providing the geotechnical report failed to take into account in his site classification the presence of the very large tree identified by him in the geotechnical report. Mr Davis agreed in cross-examination that if the site was classified by Mr Jenkins as a “P” site, not an “S” site, then he had addressed any problem created by the large tree through the use of piers. I have found that Mr Jenkins correctly classified the Shergar site as class “P”. Further, I note the report expressly classifies the site as “P” because of cut to fill and tree stump holes. The report identifies a very large tree in the likely building footprint. The report includes three further notes and recommendations for dealing with large tree stump holes. Accordingly this complaint is not made out as evidence of unsatisfactory professional conduct.
  14. [155]
    Allegation at paragraph 49(c): that Mr Jenkins did not drill any boreholes or undertake any laboratory tests to assess the nature and moisture reactivity of the foundation strata. In cross-examination Mr Davis agreed the allegation had been dealt with. On the basis that Mr Jenkins was not obliged under the Standard to undertake those tests, I find that the complaint is not made out as evidence of unsatisfactory professional conduct.
  15. [156]
    Allegation at paragraph 49(d): that Mr Jenkins provided confusing and unclear references in the Amadeus site report. In cross-examination Mr Davis did not maintain the allegation. I find that the complaint is not made out as evidence of unsatisfactory professional conduct.
  16. [157]
    Allegation at paragraph 49(e): that MR Jenkins failed to provide a description of the soil at the Amadeus site which is in accordance with the requirements of AS17286. In cross-examination Mr Davis did not maintain the allegation and agreed the allegation had been earlier dealt with in terms of the use to be made of the report by Mr Jenkins as designer. He agreed that AS17286 is not a reference document for AS2870 and that  Mr Jenkins’ report referred to soils and rocks for ease of reference and to make a more complete report. I find that this complaint is not made out as evidence of unsatisfactory professional conduct.
  17. [158]
    Allegation at paragraph 49(f): that Mr Jenkins made an incorrect judgment in his report as to moisture content change at the Amadeus site. In cross-examination Mr Davis agreed that he did not deal with this allegation in his report. I find that this complaint is not made out as evidence of unsatisfactory professional conduct.
  18. [159]
    Allegation at paragraph 49(g): that Mr Jenkins report provided movement ranges against each class that are not in accordance with AS2870 and therefore provided the classification classes table in error. Mr Davis agreed in cross-examination that this allegation is similar to the allegation at paragraph 32AD where he acknowledged that the different methods adopted will result in different results. The complaint is not made out as evidence of unsatisfactory professional conduct.
  19. [160]
    Allegation at paragraphs 82(a) and 87(a) and (b): that in providing his report for the Carrigan and Caithness sites, Mr Jenkins failed to have regard to the geotechnical investigation undertaken by APOD in determining the site classification and chose to ignore the APOD investigation work and adopt his own methodology. In cross-examination Mr Davis agreed that the APOD investigation had been referred to by Jenkins. He agreed that he could not say that Mr Jenkins has not had regard to the APOD investigation. Mr Davis agreed that Mr Jenkins had gathered information for the purpose of design of the footing system, however, how he uses the information is a question for design. I find that the complaint is not made out as evidence of unsatisfactory professional conduct.

Has unsatisfactory professional conduct been established?

  1. [161]
    The Board has submitted the definition of unsatisfactory professional conduct has been met.
  2. [162]
    It submits that Mr Jenkins has engaged in conduct that is of a lesser standard than that which might reasonably be expected of the registered professional engineer by the public or the engineer’s professional peers. In this regard the Board says that both the public and professional peers expect compliance with the relevant Australian Standard.
  3. [163]
    The Board relies on the decisions of Board of Professional Engineers of Queensland v Lennox [2008] CCT ED013-06 and Board of Professional Engineers of Queensland v Hammond [2012] QCAT 626. Those cases involved site classifications of “H” and “E” respectively. The engineers in those cases were found not to have complied with AS2870, resulting in a finding of unsatisfactory professional conduct. In this case I have found that the sites have been properly classified as “P” which take them outside the requirements of the Standard. 
  4. [164]
    I have accepted the expert opinion of Mr Fox that neither AS2870 nor AS1726 prevents the use by Mr Jenkins of the methods adopted by him. Mr Jenkins has in any event utilised the methods in the AS2870 as part of his site investigation methods.
  5. [165]
    Mr Jenkins has submitted that the Board has not called evidence from the peers of Mr Fox. Given that Mr Davis’ professional work does not involve design of residential footings and slabs, I agree with Mr Jenkins that he is not his peer. I agree with Mr Jenkins that given the qualifications of Mr Fox, he is a peer whose evidence I should accept. I agree with Mr Jenkins that the Board’s case is missing any evidence about what another reasonably competent engineer would do on each of the 11 sites the subject of complaints.
  6. [166]
    For these reasons I find that this limb of the definition of unsatisfactory professional conduct has not been met.
  7. [167]
    In relation to the second limb of the definition, a raft of allegations have been made against Mr Jenkins as evidence of incompetence, lack of adequate knowledge, skill, judgment or care in the practice of engineering. Particulars include – showing contempt for the Standard, deficiencies in site investigation and reporting, failure to classify sites in accordance with section 2 of the Standard, failure to meaningfully engage with AS2870’s methods for determination of soil reactivity at all, failure to examine the soil profile to not less than 1.5 m with a minimum of one borehole per house site and significant under-estimation of the reactivity of the site classification, resulting in footing system designs with significantly less stiffness than the standard designs under AS2870 for the actual site classification. For the reasons set out earlier in this decision I have not found any of these allegations to be made out. I have not found the allegations set out in the Further Amended Application to be made out. I have found that there is no evidence of unsatisfactory professional conduct related to the allegations against Mr Jenkins.
  8. [168]
    Some other serious allegations are made against Mr Jenkins in the Board’s submissions, which it is appropriate to address separately. It is asserted by the Board that for most of the 7 sites identified in this proceeding the footing system falls well short of the stiffness requirements of the standard designs under AS2870 for actual site classification. I am asked to draw an inference that the motivation for this was cost. The basis for the assertion is said to be that Mr Jenkins has designed a class “S” footing system and has classified the sites as Class “S”, in order to save cost.
  9. [169]
    This submission bears no relationship to the evidence or the concessions made by the Board’s expert Mr Davis.
  10. [170]
    First, Mr Davis acknowledged that he was not qualified to make assertions in relation to design of the footings and slab. There is no evidence to support the Board’s submissions in relation to stiffness of the slabs. It is misconceived to attempt to compare the Standard deemed to comply designs with the designs in fact applied at the sites. Deemed to comply designs in the Standard do not apply to the site because of its “P” classification.
  11. [171]
    Secondly, I have found that the sites are classified as “P”. I have found that Mr Jenkins did not classify the sites as “S”. I have found that he did not design the footing systems for class “S” sites. Mr Davis admitted that if the sites had been classified as class “P” then his complaints were wrong.
  12. [172]
    Third, there is no evidence of the cost of various designs before the Tribunal which might substantiate an assertion that Mr Jenkins designs were motivated by cost not site requirements.
  13. [173]
    I reject the submission and refuse to draw an inference that Mr Jenkins was motivated by cost.
  14. [174]
    In relation to the Board’s complaints about the geotechnical reports prepared by Mr Jenkins, it is submitted that they contain serious deficiencies and with respect to soil profile are an educated guess or at worst a fiction.
  15. [175]
    I do not accept these submissions. It was not put to Mr Jenkins that he was lying or that there was anything untoward in a lack of detail in his reports. I have accepted Mr Jenkins evidence that the reports are intended for his own use in designing the footing system. I agree with Mr Jenkins that there is no evidence from any Council about what use is made of the investigation report or that it is unsatisfactory for Council purposes.
  16. [176]
    It is suggested in the Board’s submissions that doubt is cast on Mr Jenkins claims to have determined soil profile by observation of cuttings. I accept Mr Jenkins evidence that he saw cuttings usually at the site next door. I agree with his submission that there is no allegation by reference to the Further Amended Application that he has not identified the location of cuttings.
  17. [177]
    I find that the Board has not established unsatisfactory professional conduct on the part of Mr Jenkins.

Orders

  1. [178]
    The application is dismissed.
  2. [179]
    Any submissions in relation to costs to be made by Mr Jenkins should be filed and served by 5 January 2016. Any submissions in reply should be filed and served by 26 January 2016.

Footnotes

[1]See the comments of Peter Davis in the joint expert report following an Experts’ conclave held on 29 May 2015 and Exhibit 5 in the proceedings – report of Eric Fox, dated 5 June 2015.

[2]Exhibit 3 – Affidavit of Peter Alan James Davis, attachment “PD-16” – Investigation Report, 359.

[3]Exhibit 7 Australian Standard Residential slabs and footings – Construction, 5.

Close

Editorial Notes

  • Published Case Name:

    Board of Professional Engineers Queensland v Colin Jenkins

  • Shortened Case Name:

    Board of Professional Engineers Queensland v Jenkins

  • MNC:

    [2015] QCAT 553

  • Court:

    QCAT

  • Judge(s):

    Member Fitzpatrick

  • Date:

    10 Dec 2015

Appeal Status

Please note, appeal data is presently unavailable for this judgment. This judgment may have been the subject of an appeal.

Cases Cited

Case NameFull CitationFrequency
Board of Professional Engineers of Queensland v Hammond [2012] QCAT 626
1 citation
Jump To
Cite 1 - [2012] QCAT 626
Board of Professional Engineers of Queensland v Lennox [2008] CCT ED0 13-06
1 citation
Jump To
Cite 1 - [2008] CCT ED0 13-06

Cases Citing

Case NameFull CitationFrequency
Col Jenkins & Associates v Queensland Building and Construction Commission [2019] QCAT 1171 citation
1

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