If you are submitting designs and the relevant Building Consent Authority has asked you to show explicit compliance for B2 durability, you may have been wondering how to do that.

If you are submitting designs and the relevant Building Consent Authority has asked you to show explicit compliance for B2 durability, you may have been wondering how to do that.  You may have been asked to show compliance for B2 by completing a producer statement (PS1).

Engineering New Zealand and ACENZ have been working with Auckland Council, Christchurch City Council and MBIE to explore whether existing regulations allow engineers to show compliance for durability for all materials used, and whether producer statements are suitable for showing compliance to B2.

We recommend that compliance for durability be provided only on a material-by-material basis. To do this, submit a letter to the Building Consent Authority tailored to the materials that you have specified in the design. Download one of the example letters that details the durability standards relevant to timber treatment, concrete cover and steel protection. Current regulation provides acceptable solutions only for a limited number of materials.

If you are being asked to show compliance for B2 during the construction phase, supply a letter detailing only those materials you can verify have been correctly used in the construction, according to the consented design. Poured concrete is one material that an engineer could verify. Together with ACENZ we are developing an example letter for construction monitoring and durability, and we will let you know when this is available.

In our view, producer statements are not suitable for showing compliance to B2. 

We are keen to work with Building Consent Authorities on your behalf, so please contact us if you would like help working through any B2 compliance matters.

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