Foam Cavity Wall Insulation Problems

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.

Foam cavity wall insulation problems.

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. Spray foam installers missed some of the air leakage sites. Better yet remove it. What is a cavity wall.

A cavity wall is a double layered masonry wall on the exterior of a home. Damp walls as one of the most well known problems with cavity wall insulation damp is an issue that no homeowner wants to see. 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 enough siding to jimmy the foam out probably 2 3 pieces per story per wall cavity.

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. So how is cavity wall tie failure linked to problems with cavity wall insulation. In order of prevalence here are the problems i ve seen with explanations following the list.

I ve seen a number of houses with problems even though they re insulated with spray foam. Remove the foam to reinsulate. Cavity wall insulation can cause damp. Yes you can use expanding foam insulation in cavity walls.

If left unaddressed long term it can lead to all manner of problems include mould and mildew. Find out if your home s likely to be affected. 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. 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.

Spray foam insulation is a better insulator than mineral wool loft insulation as you need less of it to get the same insulating effect. Reinsulate with dense packed cellulose still my personal. In some cases the damp and mould resulting from cwi can cause health problems or exacerbate existing conditions particularly respiratory conditions.