The NZ Metal Roof and Wall Cladding Code of Practice is a comprehensive design & installation guide, and a recognised related document for Acceptable Solution E2/AS1 of the NZ Building Code.
NZBC E2 – External Moisture is primarily focussed on a buildings’ external envelope being able to resist weather infiltration.
Acceptable Solution E2/AS1 also has some information on gutter sizing and durability, but these are also covered in E1 – Surface Water and B2 – Durability.
E2/AS1 also has some prescriptive solutions for structure regarding roofing spans which are omitted from B1 - Structure.
For clarity, this Code of Practice deals with the following topics discretely:
- Resistance to loads in 3 Structure.
- Durability covered in 4 Durability
- Gutter design covered in 5 Roof Drainage .
- NZBC E2 Compliance requirements in 6 External Moisture Overview.
- Managing water ingress of metal roof and wall cladding in 7 External Moisture Roofing.
- Managing water ingress through flashings in 8 External Moisture Flashings.
- Managing weathertightness of penetrations in 9 External Moisture Penetrations.
- Managing Internal Moisture is covered in 10 Internal Moisture.