The following questions provide an outline of common queries regarding Gradient Insulation’s products. For further information, please see our product literature and detailed installation guides, or contact the Gradient service helpdesk.
One common method is to use a self-adhesive aluminium foil tape. Depending on the proposed construction, taped board joints may act as a vapour control layer (VCL) on their own or be used in conjunction with a conventional sheet VCL like polythene.
Abutments with other construction elements should be sealed with a low modulus silicon sealant.
Downlighters should not be recessed into insulated ceilings if they penetrate the vapour control layer (VCL). This will result in them drawing warm moist air into the roof space where it could condense and drip back out of the fitting, causing a potential fire risk.
Where downlighters are to be used they should be fitted into a false ceiling below the structural ceiling.
Overheating can occur where thermal insulation is laid over existing downlighters and any associated transformers that are not designed to operate under these conditions. Cables and other electrical equipment should not be covered by insulation.
In all cases, the downlighter manufacturer's instructions should be followed. They should specify the amount of space to be left around the back of the fitting, its fire rating, whether it can be covered with insulation, and the type/wattage of suitable lamps.
If in doubt, consult a qualified electrician.
If in doubt, seek advice from your Building Control Officer.