Description

There are many ways to increase thermal performance in external walls – for example, a secondary insulation layer or using materials, such as structural insulated panels (SIP).

One way to improve performance is to increase the exterior wall framing depth from 90 mm to 140 mm to accommodate thicker bulk insulation.

The increase in the total upfront build cost will be offset by reduced operating costs (particularly heating costs) for the building’s service life.

Scope

This Bulletin includes:

1. Introduction
2. Improvement in thermal performance
3. Other advantages of 140 mm framing
4. Requirements in NZS 3604:2011
5. Specifying 140 mm framing versus secondary insulation
6. Resources