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Insulation for Upgrading Concrete Slab Floors

PIR insulation is perfect when refurbishing the ground floor of a construction to comply with Building Regulations.

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Converting existing unheated basements, garages and storage areas into habitable rooms is a popular way of increasing living space without constructing an extension. Such spaces typically have a sound, level concrete slab floor - but no floor insulation to help achieve thermal performance targets for new habitable rooms.

If headroom is tight then the only option may be to break up the existing slab, dig further down and build up an entirely new floor. Where it’s possible to avoid that, however, upgrading the floor slab is a viable solution, adding a damp proof membrane (DPM) if not already present before installing the insulation.

Headroom is unlikely to be limitless though! So it makes sense to keep the make-up of the floor upgrade as thin as possible, which means using a high performance insulation product. Lightweight, rigid polyisocyanurate (PIR) foam insulation boards, such as those manufactured by Celotex, are among the most thermally efficient, commonly available insulation materials.

They are easily handled, meaning floors are quickly insulated ready to receive a light-gauge polythene separating layer and - depending on the height available - either a concrete screed or a thinner tongue and groove chipboard.


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Celotex products to consider

Celotex XR4000
1200 x 2400mm
0.022 W/mK

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Celotex GA4000
1200 x 2400mm
0.022 W/mK

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Celotex TB4000
1200 x 2400mm
0.022 W/mK

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