Foam Cavity Wall Insulation Problems

I ve seen a number of houses with problems even though they re insulated with spray foam.

Foam cavity wall insulation problems. 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. So how is cavity wall tie failure linked to problems with cavity wall insulation. If left unaddressed long term it can lead to all manner of problems include mould and mildew. In some cases the damp and mould resulting from cwi can cause health problems or exacerbate existing conditions particularly respiratory conditions.

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. 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. When we went undercover to investigate the quality of insulation suitability inspections in 2011 our findings suggested that you can t always rely on assessors to carry out thorough inspections or warn of potential damp problems even those from big brands such as marks spencer npower and tesco. Better yet remove it.

Reinsulate with dense packed cellulose still my personal. So here s the part that sucks for me what has to be done to fix the problem. Cavity wall insulation can cause damp. A cavity wall is a double layered masonry wall on the exterior of a home.

What is a cavity wall. 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. Yes you can use expanding foam insulation in cavity walls.

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. Remove the foam to reinsulate. 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. In order of prevalence here are the problems i ve seen with explanations following the list.

Find out if your home s likely to be affected. 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. Spray foam installers missed some of the air leakage sites.