The language of smart homes

Thermal envelopes

The walls, windows, doors, floors and ceilings of a structure all form the thermal envelope. A good 'envelope' wraps around a house to help prevent warmth getting out, and cold getting in.

Thermal breaks

Some materials are poor insulators. For example, commonly-used aluminium window frames will stay cold and suck warmth out of a room, even if you have a heater blazing away inside. The cold aluminium meeting the warm air also creates condensation, leading to mould.

A thermal break (or thermal barrier) is an insulation material placed inside or around a product or structure, to reduce or stop heat getting out, and cold getting in.

Thermally-broken aluminium windows are made up of separate frames (one inside, one outside), with a layer of thermally-resistant plastic between them (the ‘break'), which insulates the frame.

Timber, UPVC and fibreglass window frames are highly insulated.

Thermal bridges

Some products, like insulation, are thermally resistant. They slowly transfer heat which helps to keep a room warm for long periods.

Standard 90mm timber framing doesn't have good insulation properties. It's a ' thermal bridge' because it transfers heat out of a structure at a fast rate.

The more complex the design of a house, the more 'bridges' you'll have. The more ‘bridges', the higher the loss of heat, and the more it will cost to keep the house warm.

Julie's house doesn't have the 'bridges' found in standard NZ builds, thanks to her use of CLT panels and wood fibre insulation.