The house has been built with ‘passive house’ principles in mind, with extensive insulation and an air-tightness barrier paired with a ventilation system, to reduce the energy requirement for heating and cooling the home. 

To minimise energy loss, the 170-square-metre, four-bedroom house is to be built with a double layer of insulation in the walls, separated by a building wrap and battens, to eliminate thermal bridging.  Bradford Gold glass-wool insulation segments with R-values of 2.8 and 1.0 have been specified, giving a combined R-value of 3.8. 

Bradford Gold Hi-Performance segments with an R-value of 7.0 have been specified for the ceiling.  CSR Bradford marketing manager Chris Kenny says the company has utilised advanced technology to produce a product with the highest single-layered R-value of any New Zealand glass-wool insulation.

To stop heat escaping through the floors, Bradford’s Optimo underfloor insulation with an R-value of 2.6 will be installed. 

All the insulation will be installed by a Bradford-approved installer, to ensure quality and thermal performance.  Kenny says correct installation of insulation, though often overlooked, is a critical component in ensuring its performance integrity. Christchurch-based E Insulation, which has both IAONZ certification and a long service record for quality installations, has been chosen as the installer for this project.

Bradford Gold insulation recently received ‘sensitive choice’ endorsement from the Asthma Foundation of New Zealand, indicating its suitability for use in the homes of asthma and allergy sufferers – the only insulation on the New Zealand market to achieve this accreditation.  The Arlanda fibre used in Bradford Gold also has low VOC emissions and a recycled content of up to 80%.