Special provisions apply for the installation of insulation near downlights. Where this occurs, it can increase fire risk if there is insufficient clearance and air ventilation around electric lights and fittings.
As a result of these concerns, Standards Australia has issued rules which require a clearance of 200mm around lamps and transformers. Any combustible building material must be kept at least this distance from the lights as a protection from heat generation.
Installing recessed downlights throughout a home decreases its energy efficiency by at least 10%, particularly as large gaps are currently required by building regulations to be left around each downlight. Builders need to be aware that each downlight creates a significant thermal gap, and industry observers believe that this loss of thermal performance will soon be recognised by energy efficiency programs such as AccuRate and Bers – making it unwise for downlights to be installed into a home unless a locally designed cover, designed to accept insulation being placed over it, is used. Again, using these specifically designed downlight covers has been standard practice in the US & Europe for a number of years.
BRANZ research shows that a 4 mm gap in insulation fitted to a ceiling will result in a 50% loss in insulation performance, so even the tiniest installation gaps must be avoided. This research outcome has also been supported by the CSIRO.
Acknowledgements: ThermoSealed BATTS