Changes that Government is making to the building code will impact builders of new homes in the pocket, but will also improve energy efficiency for warmer drier homes.
The changes to the H1 Energy Efficiency standards set new requirements for the thermal performance of windows and doors – where a large amount of heat is lost – as well as wall, underfloor and roof insulation.
A company riding the changes with confidence is Silverdale’s Windowmakers.
Sales and project manager, Paul Keen, says the moves could be considered “a bit of a catch up” – the new standards are still well below those of some other countries with similar climates, including Ireland, he says.
The Ministry of Business Innovation and Employment proposed the changes in consultation with the industry.
It has meant significant re-development of products, and architects having to incorporate the new standards into every home they design.
The standards for aluminium joinery are measured by thermal resistance (an R value). Until the first changes came in, last month, that R value was 0.26 – achieved with standard double glazing and non-thermally broken frames. In November last year, that standard rose to 0.37 and from November 2 this year, it will rise again to 0.46 – an overall 76 percent increase.
This means aluminium window frames will need to be thermally broken – this creates a barrier between the frame and the home. As well as double glazing, low Emissivity glass (or Low E-glass) will need to be used.
All new residential builds will need to meet the new standards, which will increase costs. Any structural changes to existing homes that need resource consent will also have to comply.
Keen says with 35-50 percent of heat lost through windows and doors, this was an area that needed to be addressed in New Zealand and will result in healthier homes.
He says some current home builders his company is working with are upgrading to meet the November standards anyway and that the industry is publicising the changes to increase awareness.
Info: search H1 Energy Efficiency at www.building.govt.nz/