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External Wall Insulation

High performance PIR insulation boards for external solid walls for refurbishment projects and applications.

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Thermal insulation is often likened to a tea cosy in the way it helps to limit heat loss. Applying insulation to the outside of the building fabric, much like the tea cosy sits around the outside of the teapot, keeps the structure as close to the internal temperature as possible.

For existing buildings, that is particularly beneficial because it protects facing materials - especially traditional brickwork - that may have been severely exposed to wind and rain over decades. Although it hides those facing materials from view, a system featuring external insulation can extend the life of the masonry and reduce its moisture content.

As well as improving the performance of the building and helping to preserve the existing fabric by eliminating condensation risks, externally applied insulation does not impact on floor space and reduce room sizes.

Of course, adding insulation to the outside of a building has certain practical implications. External fixtures like rainwater goods and window cills have to be adapted, as does the way in which the roof meets the top of the wall, to avoid a potentially severe cold bridge. The property needs to have a certain amount of space around its outside to accommodate what might be a substantial insulation thickness.

In anything other than a detached property, there is the matter of finishing the insulation where one property becomes another. More fundamentally, changing the aesthetics - particularly of a property with historic value - may not be considered acceptable. In other situations, however, it might contribute positively to an area.

Lightweight polyisocyanurate (PIR) boards, being among the most thermally efficient commonly available insulation materials, can be installed between timber studs and protected by an appropriate weather-resistant finish, to deliver long-term energy savings from the thinnest possible solution.


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Celotex products to consider

1200 x 2400mm
0.022 W/mK

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1200 x 2400mm
0.022 W/mK

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