Open Cell Vs Closed Cell Spray Foam Roof Humid Climate

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.

Open cell vs closed cell spray foam roof humid climate.

Spray polyurethane foam spf can do stuff that no other stuff can do. The microscopic cells within open cell foam are just that open which give it a soft fluffy feeling. So what is it with the family food fight. Kit 105 sf coverage.

We often compare the texture of open cell foam to a sponge or even angel food cake. Murmurs and hearsay about open cell spray foam insulation have been gaining traction for a while. Open cell spray foam insulation doesn t store the moisture. It s the wood decking that stores the moisture though.

Since vapor retarder paint wont work unless drywall is first installed on the interior side of the closed cell spray foam and since installing drywall is expensive most cold climate builders avoid the use of open cell spray foam in attics. Closed cell foam is made up of cells that are as the name suggests completely closed. It s just a pathway. In addition to the situation specific considerations there are more general considerations to make when deciding between open cell and closed cell foam.

It rots roofs people have told me. Closed cell foam is much denser than open cell foam. Quick cure best seller kit 605 sf coverage best seller kit 205 sf coverage. Kit 60 sf coverage.

Most open cell foam has. Because of this closed cell foam is much more rigid and stable than open cell foam. Low density open cell is better than high density closed cell or is it vice versa. Because the open cell structure allows some vapor to pass through open cell foam is a good choice in hot humid climates and under roof sheathing such as in conditioned attics where water vapor caught between insulation and sheathing could promote wood rot.

Kit 205 sf coverage. Folks i have got news for you regarding the open cell closed cell thing. There is no wrong answer. On the interior side of any open cell spray foam installed on the underside of roof sheathing.

For example closed cell foam is really the only option for residential roofing adhesive due to its strength characteristics. Fire rated e84 kit 605 sf coverage. Not long ago someone even told me that in florida roofing companies won t let their workers go up on roofs with open cell spray foam because the roofs are so spongy the guys fall right through. The cells are pressed together so air and mositure are unable to get inside the foam.

Closed cell spray foam on the other hand is also called medium density or 2 0 lb foam.