Concrete New Zealand publishes new Alternative Solution

Last updated in 2014, Concrete New Zealand has published an update to CP01 Code of Practice for Weathertight Concrete and Concrete Masonry Construction to improve thermal performance and account for new construction systems

The CP01 Code of Practice for Weathertight Concrete and Concrete Masonry Construction covers the weathertightness of the building envelope for concrete slab on ground, concrete and concrete masonry wall systems, concrete flat roofs and decks and concrete to timber construction junctions. It also provides weathertightness detail for four alternative positions for wall insulation:

• On the inner face of the wall.
• On the outside face of the wall (EIFS systems).
• Integral within the wall itself.
• Within a ventilated cavity.

The update will include new acceptable surface temperature factors and reflects the range of new weathertightness systems that have become more prevalent in New Zealand over the past 10 years.

“The addition of acceptable surface temperature factors will also help architects and designers determine a detail’s climate zones suitability,” says Concrete NZ, “while new Appendix A describes the methodology that was used to develop the detail and provides further thermal performance information.”

The 2022 update also includes thermal images of the Code’s details “to enable a better understanding of the risk of condensation on internal surfaces and at junctions”.

It has been prepared for use by practitioners with the appropriate qualifications, experience and professional judgement as a way to demonstrate compliance with the Clause E2 External Moisture. It should be assessed as an Alternative Solution, while the current 2014 version remains the cited version in Acceptable Solution E2/AS3 and should be assessed as an acceptable solution for Clause E2 External Moisture.