About this document
A practical and easy-to-follow guide that explains how to construct drained and vented cavities for timber-framed buildings to ensure they are well built and healthy. It is targeted for people involved in design, construction and weathertightness compliance.
For timber-framed buildings in New Zealand, recent science and research has identified ‘drainage’ and ‘drying’ of water as critical functions of cavities.
This booklet will help you construct cavities according to E2/AS1 to help ensure buildings are well built and healthy. Note that E2/AS1 is amended from time to time, and the most recent version of E2/AS1 should be referred to for compliance with the Building Regulations.
It sets out the importance of designing for weathertightness, including:
- when cavities are needed
- installing wall underlays
- cavity battens
- closing off the top cavity
- drainage and ventilation
- cavity walls over two storeys
- installing window and door joinery
- air seals.
Note that it does not explain the cavity behind masonry veneer wall claddings.