Insulation for Timber Frame Wall

ISOVER-timber-frame-wall-insulation 10B_Walls_Timber-Frame-Wall
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An increasingly popular way of constructing new-build dwellings is to use a timber framed construction rather than traditional masonry cavity wall construction. Building with timber framed construction can offer a number of advantages and benefits over building with a more traditional form of construction, such as lighter weight and a higher speed of construction.

In a timber-framed wall, insulation is typically installed between the studs. This insulation can be PIR (Celotex GA4000 or XR4000 can be considered) or glass mineral wool (ISOVER Timber Frame Roll or Batt can be considered).

Depending on U-value requirements, there may be additional insulation required. This can be placed outside the sheathing board (i.e. within the external wall cavity); products such as Celotex GA4000, Celotex XR4000 or ISOVER Polterm Max Plus can be considered.

Insulation could also be installed internally on the warm side of the studwork, such as a plasterboard laminate (PL4000 can be considered) or a PIR insulation board (Celotex TB4000 or GA4000 can be considered) alongside a separate layer of plasterboard.

Key Considerations

When using Celotex or ISOVER products, you need to satisfy yourself that use of the product meets all relevant national Building Regulations and guidance as well as local, national and other applicable standards relevant for your construction or application, including requirements in relation to fire and applicable height restrictions. In addition to the product datasheet, please refer to the following product documents:

Celotex products should not be used in the external walls of buildings over 11 metres in height. Recent changes to Building Regulations mean that only non-combustible insulation or insulation of limited combustibility should be used in buildings of that height.

The building detail is for illustrative purposes only. It does not constitute advice and should not be relied upon.


Insulation products
Product Name Thickness Range Sizes Lambda
Celotex GA4000 50-100mm Width 1200mm, Length 2400mm 0.022
ISOVER Timber Frame Roll 32 90-140mm Width 2 x 0.57m, Length 2.7 - 4.2m 0.032
ISOVER Timber Frame Roll 40 90-140mm Width 2 x 0.57m, Length 6.5 - 10.13m 0.040
ISOVER Timber Frame Batt 40 90-140mm Width 570mm, Length 1175mm 0.040
ISOVER Timber Frame Batt 35 90-150mm Width 570mm, Length 1175mm 0.035
ISOVER Timber Frame Batt 32 50-140mm Width 570mm, Length 1175mm 0.032
Celotex XR4000 110-200mm Width 1200mm, Length 2400mm 0.022
Celotex TB4000 20-40mm Width 1200mm, Length 2400mm 0.022
Celotex PL4000 25-65mm (+12.5mm Plasterboard) Width 1200mm, Length 2400mm 0.022
ISOVER Timber Frame Roll 35 90-140mm Width 2 x 0.57m or 3 x 0.4m (140mm only), Length 4 - 5.3m 0.035
ISOVER Polterm Max Plus 50-200mm Width 600mm, Length 1200mm 0.035
ISOVER Timber Frame Batt 43 90-140mm Width 570mm, Length 1175mm 0.043