Liquefaction-prone ground needs to be mapped
We’ve changed B1/AS1 to require robust foundations for liquefaction-prone ground. This change is already in place in the Canterbury region, and will now be extended to all of New Zealand. This will provide clarity to both councils and engineers, ensuring new buildings are being built safely and strongly enough to withstand liquefaction risks.
The November 2019 update is the third installment in the biannual Building Code consultation, which is part of the overall programme to improve the New Zealand Building Code. Of particular note is limiting the application of the B1 Acceptable Solution B1/AS1 so that it may not be used on ground prone to liquefaction or lateral spreading.
The focus on liquefaction and lateral spreading is a result of the experience of the Canterbury earthquakes and responds to recommendations made by the Royal Commission of Inquiry. The application is limited to the Canterbury region but the change would extend this to all of New Zealand.
Reason for making this change
To provide clarity to Territorial Authorities (TAs), Building Consent Authorities (BCAs), engineers and developers, producing safer and more resilient outcomes for all buildings. In particular, BCAs will have flexibility to determine how to best mitigate the risk posed by liquefaction and lateral spreading in their region.
Other improvements to the Building Code
See the full list of changes in the November biannual Building Code at the Building Performance website.