Open Cell Foam Insulation Moisture Problems

The spray foam insulation chemicals weren t mixed properly.

Open cell foam insulation moisture problems.

Open cell s vapor permeability enhances an assembly s ability to dry out via diffusion should it become wet open cell spray foam may absorb moisture if subjected to hydrostatic pressure but will allow moisture to drain through open cell spray foam will not wick water or contribute to capillary action. Remember that open cell spray foam is also an air barrier. According to the epa spray foam insulation is one of the best insulation materials used to minimize moisture related problems that are caused by random air leakages that fill all the cracks and crevices where air can enter into the environment. Foil faced rigid foam insulation 2 in.

Compared to traditional insulation whether fiberglass or cellulose spray foam has the potential to provide better performance via its air sealing properties high r values per inch of thickness and in the case of closed cell spray foam ability to repel moisture. Choose open cell spray foam when insulating roofs since closed cell foam can trap water from a leaking roof damaging the framing material and roof sheathing. Thick applied beneath and spanning the floor joists held on with cap nails and seams taped edges sealed with a foam sealant is a tested good solution. Lstiburek takes blame for bad language.

It s the wood decking that stores the moisture though. For example icynene open cell spray foam must be installed at 3 inches before an air barrier is created. Be sure to have that discussion with your licensed contractor and don t be afraid to double check the information before the project begins. Open cell spray foam insulation doesn t store the moisture.

50 pascals of air movement is equal to about 16 mph wind. 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. It is lower cost than closed cell foam and has the plus of flexing with the building but can be tricky to get good paint skin coverage. It has a relatively high vapor permeance 3 perms at a thickness of 6 allowing water vapor to migrate to the roof decking at night and back into the attic air in the daytime.

According to frank moisture can be a concern if you construct a home and insulate it with open cell spray foam. It s just a pathway. Over time trapped moisture can cause serious problems. Oh and when you put it in your attic spray foam.

Many homeowners love spray foam insulation and it s easy to understand why. Open cell spray foam will allow moisture to get to the metal surface.