“The Hunn Report” 2002
Report of the Overview Group on the Weathertightness of Buildings to the Building Industry Authority
This document was a landmark report officially confirming that New Zealand had a serious problem with its buildings, and is arguably the moment when ‘leaky building’ publically became a dirty and loaded word. The Hunn report dramatically underestimated the potential cost of the problem at $240 million, but did lay the groundwork of much of the changes made to Government policy ove rthe coming years.
The Terms of Reference for the Hunn Report
- The nature, extent and effect of the current failure of some buildings to deal with moisture in and through their exterior envelopes.
- Potential contributing causes such as, but not limited to: a) Inadequacy in the Building Code and Approved Documents b) Inadequate documentation supplied for building consent c) Insufficient checking at building consent, during construction, and at Code compliance stages d) Inadequacy of building products, materials and components, including evaluation of their suitability or fitness for purpose e) Insufficient technical information provided by manufacturer¡¯s literature and instructions f) Inadequate contract documentation g) Inadequate trade skills and supervision on site h) Lack of co-operation and sharing of responsibility on site
- Whether failures are attributable to deficiencies in the Building Act, the Building Regulations, or in the manner in which these are administered by the Authority or by Territorial Authorities (including the role of Building Certifiers), and whether the purposes and principles of the Act under Section 6 have been properly observed and followed by the Authority.
- Any other matters that are considered relevant to the inquiry.
Weathertightness Recommendations from the Hunn Report
- That the BIA: a) issue a public warning concerning the risks of collapse of cantilevered balconies and decks supported by untreated timber framing; and b) resolve with Territorial Authorities how the public warning is to be followed up with appropriate procedures to ensure the risk is widely recognised and appropriate corrective action taken where necessary.
- That the BIA: resolve with the Public Health Division of the Ministry of Health the best manner by which the potential health risks associated with fungal decay can be identified and the precautions that need to be taken, particularly when the removal of cladding exposes decayed timber framing. This information must then be disseminated to the public and the building industry.
- That the BIA in revising its Approved Documents E2/AS1 External Moisture: a) continue with its intention to exclude for the time being from the Acceptable Solutions, face-sealed cladding systems in high risk areas b) sponsor research into developing effective moisture management systems suitable for New Zealand conditions where there is a high risk of leakage c) include in the Approved Documents the use of such moisture management systems when their efficacy is assured.
- That the BIA in conjunction with the Building Officials Institute of New Zealand (BOINZ): a) review and upgrade the criteria for what constitutes a reasonable level of detail to be provided with building consent applications with respect to weathertightness detailing including flashings. b) review and develop guidelines for an inspection regime as part of the code compliance certification process, with specific reference to weathertightness aspects.
- That the BIA : a) develop more prescriptive Acceptable Solutions and Verification Methods for the Approved Documents B2 Durability and E2 External Moisture; b) develop recommended procedures and processes for the development and approval of Alternative Solutions; and c) promote with Standards NZ the development of a national performance-based Standard for domestic building weathertightness.
- That the BIA: review the current practice for product appraisal and develop formalised requirements. This should include establishing specific criteria for the process; accrediting and/or auditing appraising bodies; monitoring ongoing product performance; and establishing and maintaining a register of the ¡®approved¡¯ products. It would seem sensible to explore the possibility of better alignment of Australian and New Zealand practice.
- That the BIA: a) take on a broader and more proactive responsibility to establish, fund, monitor and audit public-good research across the building sector; and b) establish an independent research programme to investigate the nature and extent of the weathertightness problem in New Zealand and gain better understanding of the causes of the current failure of some buildings to deal with moisture in and through their external envelopes.
Building Sector Recommendations
- That the BIA discuss with the Minister of Internal Affairs the desirability of: a) convening a meeting of leaders of the building and associated sectors to discuss the issue of weathertightness, to explore the means by which the current disturbing trends can be halted and to agree on actions which might be taken to improve the performance of the sector in future, and b) a public enquiry into the building industry (similar to the one recently conducted in New South Wales) which would have the mandate to look beyond the issue of weathertightness alone and to examine the range of issues which have emerged from this and other reports.
- That the BIA: a) discuss with the Department of Internal Affairs the philosophy of ¡°minimise compliance cost¡± with a view to ensuring that the current or any future review of the Building Act promotes the concept of improving compliance process efficiency without compromise to building standards or quality; b) in any review of Approved Documents consider the concept of optimised ¡®whole-of-life¡¯ costs as opposed to minimised capital cost; and c) in reviewing the role and responsibilities of territorial authorities and building certifiers with regard to the building consent checking process and code compliance inspection regime, ensure that any guidelines or implied or expressed incentives do not inadvertently promote ¡°down to cost¡± as opposed to ¡°up to standard¡± behaviour.
- That the BIA in conjunction with BOINZ: develop guidelines on the interpretation of the Building Act and companion documents to provide an educational and reference document for building inspectors and certifiers. It should provide guidance on the interpretation of the Building Code provisions for Objective, Functional Requirement, and Performance, and such terms as ¡°satisfied on reasonable grounds¡± and ¡°adequate¡±.
- That the BIA investigate with BOINZ: a) the issue of scope approval of building certifiers and its monitoring; and b) the split responsibility of building certifiers and territorial authorities with respect to building consents, inspection and code compliance certification; and attempt to improve and clarify both.
- That the BIA investigates the public-good benefits of a) extending the information available with LIMs to include, for instance, the inspection and maintenance recommendations prescribed by the designer (similar to the requirements for lifts and fire protection in commercial buildings), and building product or system warranties such as cladding systems; and b) introducing a form of ¡®occupation certificate¡¯;
- That the BIA in conjunction with appropriate sector groups determine: the need for developing tertiary qualifications, including programmes of continuing professional development, relevant and suitable to the knowledge, skills and experience expected of building inspectors and certifiers.
- That the BIA: initiate a formal analysis of the documentation trail to establish whether a holistic consideration of all contracts and quasi-contracts involved in the building process, set within a legislative and regulatory framework, could lead to improved definitions of the roles, functions, responsibilities and obligations of all the parties. In doing so, the BIA should examine the efficacy of adopting the concept of a home building contract.
- That the BIA: request the Building and Construction Industry Training Organisation (BCITO) to review in conjunction with appropriate sector groups the apprenticeship course in Carpentry and other key trades to ensure it delivers an appropriate balance of academic and practical knowledge and experience relevant to the needs of the individual, the industry and the consumer.
- That the BIA in conjunction with the appropriate affected sector groups: a) explore the issues involved in advocating the national registration of builders and building related trades, given the contents of this report and concerns expressed about the standards of some trade practices on-site; and b) support such advocacy if it is convinced of the benefits to the Industry.
- That the BIA: promotes debate on the issues of trade regulation, professional education and builder registration at the proposed executive forum.
- That the BIA in conjunction with the major territorial authorities: identify instances where District Plan requirements are influencing the planning and site coverage of multi-unit housing projects and consider their appropriateness in the light of this Report.
- That the BIA: discuss this Report with the Bankers Association and the New Zealand Insurance Council to ensure that both the banking and insurance sectors are kept up to date with any further developments in dealing with the issue of weathertightness.
- That the BIA having taken account of the range of matters covered in this report: a) give serious consideration to what further measures might be desirable to improve the accountability of all parties in the building sector (including owners) for the quality of construction (including weathertightness) within the framework of the current performance-based system. b) develop and implement immediately a communications strategy to keep the public and the industry fully informed of the issues and action taken.