Cavity wall insulation is the full or partial filling of the air cavity between the inner and outer leaf of a cavity wall with insulation material, such as mineral wool, EPS beads or PUR foam. It is one of the most commonly applied forms of retrofit insulation.
Application
Many older homes have a cavity wall with an open, uninsulated air gap. By filling this cavity afterwards, heat loss through the facade is greatly reduced without having to demolish the wall. The insulation material is blown or injected through holes drilled into the joints, after which the holes are closed again with matching mortar.
Characteristics
The cavity must be wide enough and free of debris to be filled properly. Mineral wool and EPS beads are blown in, while PUR is injected and expands on its own. It is important that the cavity is dry and that open perpend joints are retained for ventilation and drainage. A well-executed cavity wall insulation delivers immediate comfort gains and lower heating costs.
Related terms
- cavity
- cavity wall
- insulation
- mineral wool
- facade
- joint
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