A foam-type home insulation used in 14,000 New Zealand houses may be less effective than previously thought, research by BRANZ has found.
A study of urea formaldehyde foam insulation, marketed locally as Airfoam, was conducted by the building industry company BRANZ after complaints were received by the Energy Efficiency and Conservation Authority.
The product is pumped into wall cavities of older houses in a shaving foam-like consistency.
BRANZ says the foam shrinks when it dries, creating a gap that allows heat to escape.
But Airfoam founder John Munro questions the methodology used in BRANZ's tests.
BRANZ chief executive Pieter Burghout says the foam was studied in laboratory tests and examined in 23 homes.
He says the product has been subjected to a level of scrutiny not applied to other forms of insulation.
