Open Cell Foam Insulation Moisture Problems

Over time trapped moisture can cause serious problems.

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. According to frank moisture can be a concern if you construct a home and insulate it with open cell spray foam. 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.

For example icynene open cell spray foam must be installed at 3 inches before an air barrier is created. Sealection500 the open cell spray foam used at iowa spray foam only allows 0 001 l sm2 of air to pass through at 50ps. 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. 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 s the wood decking that stores the moisture though. 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. Foil faced rigid foam insulation 2 in. 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 s not coming from above the roof and it s not some new moisture source resulting from the 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. 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.

50 pascals of air movement is equal to about 16 mph wind. If closed cell is used the moisture cannot make its way to the wood and present. 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. It s just a pathway.

The spray foam insulation chemicals weren t mixed properly. Oh and when you put it in your attic spray foam.