Can I install downlighters in conjunction with Recticel Insulation boards?
The temperature of a lamp can reach 2000C. Without adequate ventilation to allow the escape of heat, downlighters can cause fires. Recticel recommends the following measures are taken when installing downlighters: 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.
Can PIR insulation boards be used directly below flooring tiles?
No, PIR insulation boards should not be used directly below flooring tiles, a suitable substrate such as screed should be used to distribute the load and prevent movement and cracking of the tiles.
Is a vapour control layer (VCL) required in a floor insulation application?
In addition to the damp proof membrane (normally a 1200-gauge polythene sheet below the insulation), a 500-gauge polythene VCL should be laid over the insulation. Where a concrete slab or a screed is to be poured on top, the VCL will also protect the foil face of the board from alkalis within the concrete, and stop poured concrete opening board joints and causing a thermal break.
What insulation products can be used with underfloor heating?
Recticel Insulation's Eurothane® GP boards are compatible with both wet and electrical underfloor heating systems. Clipping a wet system through the VCL described above will not compromise the performance of the VCL or the insulation.
What membranes are required in flooring application when using Recticel PIR insulation boards?
For installation on a concrete slab it is recommended that a damp proof membrane is installed below the insulation and then an additional vapour control / separating layer above the insulation before the screed / floating floor finish.
For suspended floor applications such as timber joists there should be the vapour control / separating layer included again before the finish of timber or screed.
When installing Recticel PIR insulation boards on a suspended timber floor can it be put directly onto joists?
No, a suitable timber substrate should be included over the joists (minimum 18mm) before installing the insulation.