Insulation for Suspended Timber Floors
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All ground floor constructions, unless very large commercial floors, will require some insulation to be included within the floor zone to comply with Building Regulation requirements. If the ground floor in question is of a suspended timber construction, and whether this is a renovation or new-build project, then the insulation would normally be installed in the joist zone – that is installed between the joists.
A rigid PIR board can be installed between the joists provided the insulation is cut accurately and fitted carefully to avoid air gaps, another choice would be a glass mineral wool (GMW) roll or slab – the flexible nature of this type of product means it can be cut slightly oversize and then compression-fitted between the joists to eliminate air gaps. Some support may be needed for the insulation - timber straps, timber battens or netting can all be utilised to help keep the insulation in place.
The floor would typically be finished from above with a vapour control layer (VCL) if required and a suitable timber floor deck
The building detail is for illustrative purposes only. It does not constitute advice and should not be relied upon.
Insulation products to consider
|Product Name||Thickness Range||Sizes||Lambda||BBA|
|Celotex XR4000||110-200mm||Width 1200mm, Length 2400mm||0.022 W/m.K|
|Celotex GA4000||50-100mm||Width 1200mm, Length 2400mm||0.022 W/m.K|
|Celotex TB4000||20-40mm||Width 1200mm, Length 2400mm||0.022 W/m.K|
|ISOVER Spacesaver||100-200mm||Spacesaver: Width 1160mm, Length 5200-12180mm | Spacesaver Ready-Cut: Width 3x386 or 2x580mm, Length 5200-12180mm | Spacesaver Lite: Width 1160mm, Length: 3500-7000mm||0.044 W/m.K|
|ISOVER Spacesaver Plus||100-200mm||Width 1160mm, Length 3500–7000mm||0.040 W/m.K|