Can I install External Wall Insulation on a house with cavity walls?

Yes, External Wall Insulation can be installed on properties with cavity walls, but the condition and construction of the cavity should be assessed first. Ventilated cavities can allow heat to escape before it reaches the external insulation, so details such as cavity vents and cavity closures may need to be addressed to maximise thermal performance.

If cavity wall insulation is already present, its condition should be checked. Any failed or water-saturated insulation may need to be remediated or removed before installing the EWI system.