Improving quality control in roof construction
The Building Commission of Western Australia is working with the building industry and local government to improve quality control in the residential building process.
The following four key changes to the quality control process for framed roof construction will be made:
– Ensure builders and roof carpenters have adequate information to construct roofs correctly by prescribing minimum standards of documentation at the design stage;
– Introduce mandatory inspections of completed roof framing and tie downs to ensure roofs are constructed properly;
– Consistent compliance monitoring and enforcement by permit authorities; and
– Include relevant Western Australian construction practices in the National Construction Code.
The changes respond to a number of events and audits in Australia since 2013 that have shown lapses in quality control processes around building design, certification of compliance and construction. These include a general inspection of 123 sheet metal-clad, timber frame-roofed dwellings in the Perth metropolitan and south west coastal regions in 2014.
“This was the first general inspection completed by the Building Commission using powers granted by new building legislation in 2011,” Building Commissioner Peter Gow said.
“General inspections can test how building services are being carried out, how building standards are being applied and whether building legislation is operating effectively.”
The general inspection looked at 12 critical points in timber-framed roof construction and assessed these against the deemed-to-satisfy requirements of the NCC. While variations in design and construction meant not all 12 inspection points applied to every roof, the results, when aggregated, showed only 33% of the points inspected satisfactorily met these requirements.
The inspection report concludes that some common roof construction practices in Western Australia are not covered by the deemed-to-satisfy provisions in the NCC and that documentation does not always provide builders and roof carpenters with sufficient detail on how a roof should be constructed to meet the applicable performance standards.
“Regular audits and inspections let us identify potential problem areas and work with the industry to deal with them before they pose a serious threat,” Mr Gow said.
“While non-compliance with the deemed-to-satisfy requirements of the NCC does not automatically mean a roof will not meet the performance requirements or that it will fail to perform, the findings still raise concerns for the industry and government.
“The Building Commission is working with the building industry, local government, training bodies and individual contractors to address the report’s findings.”
The Commissioner said some builders had already responded with enhanced training and improved materials and construction methods.
“The industry’s response to the general inspection report and its recommendations shows a resolve to deliver better quality assurance and improved training for trades involved in roof construction in the future.”
“Under the leadership of building ministers, regulators are also working nationally to address issues associated with non-conforming products and non-complying building practices.
“Ongoing audits show an improvement in outcomes from those identified in 2014 and the introduction of documentation and inspection standards will further support quality construction.”