Open Cell or sometimes called “soft cell” Spray Foam Insulation weighs approximately .5 lbs. per cu. ft. and has an R-value greater than R-3.8 per inch. Open Cell foam is ideal for walls that have cavities of at least 3.5″ of available space and also the underside of roofs in an attic spaces. Attics and structures insulated with open cell foam are a cost effective insulation solution that provides the highest levels of insulating properties as well as a true “air barrier system”.
Open Cell foam is by far the most common type of spray foam used in the Atlanta area and the Southeastern climates. It provides the highest levels of insulation values with all the benefits of an expanding liquid that seals and envelopes the structure and does so in the most cost effective way.
Closed Cell or sometimes called “hard cell” Spray Foam is denser than open cell and weighs approximately 2.0 lbs. per cu. ft. and has an R-value of greater than R-6.9 per inch. Closed cell foam is typically used in places where moisture is present crawlspaces, basements, under slab, or an exterior applications. Closed cell is also ideal where greater R-value is needed in a tighter space like a masonry wall with 2″ furring strips or cathedral ceilings with limited rafter space. Structures insulated with closed cell foam have the highest level of insulation properties in the industry as well as providing a moisture / vapor barrier and adding increased structural integrity to the walls and/or roof. FEMA has also determined that closed cell spray foam is an acceptable material to use in a flood zones with continuous contact with flood water without the need to be replaced, unlike traditional insulations like fiberglass or cellulose.