Envelopes Have Layers - Improving Performance and Legibility of Building Envelopes

Residential timber framed buildings in New Zealand continue to have issues in relation to performance as a result of poor initial building envelope design and a lack of construction quality.

Building envelopes need to be designed in respect to fundamental building envelope science. It is also crucial that drawings and details relating to the building envelope are clear if the desired level of performance is to be achieved. And, ultimately, the architectural drawings that are developed must be practical in respect to buildability – the construction methodology and detailing of the building envelope must be practical and achievable if the desired outcomes are to be achieved.

The legibility and identification of building envelope control layers on architectural drawings communicates building envelope performance and helps to ensure buildability of control layers, particularly in respect to their continuity during construction.

Readable (clarity) and buildable (constructability) architectural details, which respect the fundamentals of building envelope science in regard to rain, air, vapour, and heat control, can improve construction quality in New Zealand, increase building performance, and provide durable, efficient and healthy homes.

This research focuses on building envelopes constructed from timber framing as this is the most common method of residential construction in New Zealand. Common New Zealand building envelope detail drawings from a range of contexts are used to critique current New Zealand building envelope design. This analysis identifies common building envelope problems in regard to drawing readability and performance.

The research proposes a revised set of building envelope details for a timber framed terraced house, which feature an enhanced way of achieving and communicating performance and buildability within building envelope drawings and details.