Spray Foam Insulation Roof Problems

It s not coming from above the roof and it s not some new moisture source resulting from the spray foam.

Spray foam insulation roof problems.

So what are the problems with spray foam insulation. A properly done spray foam job not only insulates but also greatly reduces the air leakage of a home. The main argument against it for many years has been that any dampness getting in or condensation being caused lead to rotting of roof trusses and battens and purlins. Poor application of the spray foam insulation.

In an unvented attic scenario to limit air leakage as well as any associated condensation at the roof line a continuous air barrier is required. Insulating with spray foam insulation at the roof line will cause moisture problems with the roof sheathing. Incorrectly installed spray foam insulation can trap moisture in the home encouraging rot and mold problems. Placement errors during installation attics are the main spots in a home that are filled with unusual shapes gaps and spaces where air bubbles have the potential to form when you spray foam insulation.

But that only works if the installer can get it into the places where most of the air leakage happens. However there are still some issues with spray foam insulation on the roof that can be avoided. 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. An internet search reveals nightmare anecdotes about lingering odors having to excavate badly installed foam and health issues attributed to improperly applied foam.

Poor ventilation equals condensation when using spray foam insulation you can achieve an entirely waterproof and airtight solution but this can mean that warm air can become trapped in the space. Cost is certainly a factor spray foam is more expensive than fiber insulation but there s another side to the issue. Below we are going to list the most common problems with using spray foam insulation in your home s attic or in any area inside of your home. Spray foam insulation is a better insulator than mineral wool loft insulation as you need less of it to get the same insulating effect.

Poor application includes off ratio spraying of the material bad odors and the lack of adhesion. Moisture generated indoors or that infiltrates into the home is responsible for the bulk of the moisture in an attic insulated with spray foam on the underside of the roof sheathing. The poor application of spray foam insulation by an untrained or unlicensed contractor can lead to several problems according to fine home building. Spray foam insulation is an incomplete name.

Over time trapped moisture can cause serious problems. Lstiburek takes blame for bad language.