Reflective foil insulation provides no insulation benefit unless an air gap on the reflective side is fixed in place. A minimum air gap of 20mm is recommended but no more than 300mm.
Foil must be installed to minimise buildup of dust and condensation which can reduce surface reflectivity.
Specifying and installing foil correctly is critical in delivering long term thermal performance to meet BCA.
Where air gaps can’t be achieved or maintained, bulk insulation must be added.
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