Foam Cavity Wall Insulation Problems

Cavity wall insulation can cause damp.

Foam cavity wall insulation problems.

Yes you can use expanding foam insulation in cavity walls. If your cavity is full of insulation and no moisture water or water vapour is getting into the cavity then you re probably going to be fine. Remove enough siding to jimmy the foam out probably 2 3 pieces per story per wall cavity. Better yet remove it.

However if moisture is getting into the cavity the insulation can hold that moisture against the metal wall ties and speeding up the rusting process. So how is cavity wall tie failure linked to problems with cavity wall insulation. Until the recent fad for cavity wall insulation took hold the only times rainwater penetration was a problem was when the steel wall ties were dirty with mortar droppings and or built sloping downwards from outer leaf to inner leaf or the cavity itself was blocked at low level with mortar droppings or other debris. Expanding foam insulation has increased in popularity as the manufacturers have praised its uses and abilities and its applications have reached to include cavity walls.

Spray foam isn t thick enough. Spray foam insulation is a better insulator than mineral wool loft insulation as you need less of it to get the same insulating effect. A cavity wall is a double layered masonry wall on the exterior of a home. Reinsulate with dense packed cellulose still my personal.

Some spray foam insulation sets rigid and can also be used to help reinforce roofs that are suffering from nail fatigue when the nails used to hold slates in place rust or support cavity walls where the wall ties are failing causing cracks and bulges in walls. So here s the part that sucks for me what has to be done to fix the problem. I ve seen a number of houses with problems even though they re insulated with spray foam. When retrofit cavity wall insulation is installed into a property that is located or built in a way that means it should not have the cavities filled or if the work is undertaken incorrectly the first and most obvious sign of a problem is almost always internal dampness.

Find out if your home s likely to be affected. Spray foam installers missed some of the air leakage sites. In some cases the damp and mould resulting from cwi can cause health problems or exacerbate existing conditions particularly respiratory conditions. Damp walls as one of the most well known problems with cavity wall insulation damp is an issue that no homeowner wants to see.

What is a cavity wall. Incorrectly installed cavity wall insulation causes water to seep into a property s walls causing structural problems and damp patches that may also manifest into mould. In order of prevalence here are the problems i ve seen with explanations following the list.