aberal
Veteran
- Location
- Midlothian
I'm an architect and am against cavity fill insulation in principle. Have you ever thought why there is a cavity there in the first place? It's to create a gap between the wet outer skin and the dry inner skin. Wall ties should be free of mortar droppings and should, technically be angled down from inner to outer to ensure that there is no bridge to allow no water to penetrate from outer to inner skin. Cavities are ventilated to ensure that they remain dry. Cavity fill insulation negates all that and creates a bridge between outer and inner skin that can , but not necessarily will, allow water to migrate. It's basically a risky thing to do. Also, how can you be sure that the cavity fill insulation, which you have paid for and assume that will fill the cavity, does indeed fill that cavity. I don't believe that its a fail safe process and have always assumed that large areas can be left unfilled either by accident or design.