Masonry Cavity Wall Hybrid Insulation
- Masonry outer leaf.
- 10mm residual gap.
- Rigid insulation board specified to maintain the 10mm residual gap due to its
compressive strength. Water-tight, vapour-open polypropylene fleece outer facing that protects against moisture penetration.
Select insulation thickness and thermal conductivity in the calculator below. - 100mm (min.) block inner leaf.
Select block thermal conductivity in the calculator below. - 12.5mm (min.) plasterboard on adhesive dabs.
General construction notes
A brick and block wall where the cavity is partial filled with a special rigid insulation board that is tested and carries appropriate certification to prove that the insulation can perform in this specific way, retaining 10mm residual gap
The use of a brick outer leaf and block inner leaf means the construction does not
require the use of cavity barriers to comply with Approved Document B. The cavity must be closed at the top of the wall for the provisions of Diagram 5.3 ADBv1 to apply.
A Warranty provider may require cavity barriers.
Consideration needs to be given to the internal finishing of the wall to maintain airtightness.
ψ Value Calculator
To calculate overall U-value and ψ values follow the following steps:
