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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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External wall insulation improves the thermal performance of the building and helps preserve the existing building fabric by eliminating condensation risks. As well as keeping the structure as close to the internal temperature as possible, insulating externally does not impact on floor space by reducing room sizes.

Insulation applied externally is particularly beneficial because it protects facing materials - especially brickwork on existing buildings - that may have been severely exposed to wind and rain over decades. Although it hides the masonry from view, an external wall insulation solution can extend the life of the building fabric and reduce its moisture content.

What Celotex products are suitable for external wall insulation?

Both Celotex GA4000 and Celotex XR4000 are rigid insulation boards suitable for solid wall applications where the existing masonry can be insulated externally. The high performance polyisocyanurate (PIR) foam keeps the overall insulation thickness to a minimum and gives the following benefits:

  • Ideal where no wall cavity exists.
  • Reliable long term energy savings for buildings.
  • Particularly suited to refurbishment projects.
  • No impact on internal room space.

 Lightweight 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 facade, to deliver long-term energy savings from the thinnest possible solution.

What should I consider when insulating externally?

For new-build projects, the external wall can be constructed economically using concrete blockwork, because aesthetics do not matter. For existing buildings and retrofit projects, changing the appearance of a traditional building - particularly one with historic value - may not be appropriate. An internal wall insulation solution may need to be considered instead.

Adding insulation to the outside of an existing building has certain practical implications. External fixtures like rainwater goods and window sills have to be adapted. So does the way in which the roof meets the top of the wall, to avoid a potentially severe cold bridge.

On any building that is not a detached property, the insulation needs to be finished correctly where one property becomes another. There also needs to be enough space around the outside of the building to accommodate what might be a substantial insulation thickness.


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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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