Open Cell Vs Closed Cell Spray Foam Roof Humid Climate

Kit 340 sf coverage.

Open cell vs closed cell spray foam roof humid climate.

Closed cell spray foam on the other hand is also called medium density or 2 0 lb foam. Murmurs and hearsay about open cell spray foam insulation have been gaining traction for a while. We often compare the texture of open cell foam to a sponge or even angel food cake. So what is it with the family food fight.

Closed cell foam is much denser than open cell foam. It s just a pathway. The role of open cell spray foam. 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. On the interior side of any open cell spray foam installed on the underside of roof sheathing. Kit 60 sf coverage. For example closed cell foam is really the only option for residential roofing adhesive due to its strength characteristics.

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. Spray polyurethane foam spf can do stuff that no other stuff can do. Kit 105 sf coverage. The microscopic cells within open cell foam are just that open which give it a soft fluffy feeling.

Because of this closed cell foam is much more rigid and stable than open cell foam. Most open cell foam has. Kit 205 sf coverage. 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. 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. Folks i have got news for you regarding the open cell closed cell thing. 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. Quick cure best seller kit 605 sf coverage best seller kit 205 sf coverage. Low density open cell is better than high density closed cell or is it vice versa. The cells are pressed together so air and mositure are unable to get inside the foam.

Open cell spray foam insulation doesn t store the moisture.