Types of cell foam insulation

Let's talk about the differences between and applicatoins for open cell and closed cell foam.

Open Cell

Open cell foam contains loosely packed bubbles filled with air. It is very light weight, about 1/2 pound per cubic foot, and it is a good vapor barrier above a few inches of thickness. It is not, however a moisture barrier. Think of it as a thick sponge. When dry, it has the consistency of dry pancake batter or the foam inside a seat cushion. It is resilient, so it can be pulled off if necessary and jammed back into place. It will not move or be damaged if you have to replace the shingles on your roof.
Open cell foam is typically applied in 3-5 inch layers If you've been searching for a cost-effective way to make your home more comfortable, open cell foam insulation is an excellent option. Open cell is typically applied to roofs, attic gable-ends and 2x6 walls. It is also absorbs sound so it will make your home quieter.

Closed Cell Foam

Closed cell foam is rigid and very dense, at about 2 pounds per cubic foot.  It is incredibly efficient.  It creates bubbles using a chemical process and the bubbles do not overlap, which is why it is called closed cell.  It is both a vapor and a moisture barrier.  Closed cell foam is similar in density to the styrofoam in a beach cooler.  As you know, a 1 inch thick styrofoam cooler can keep ice and drinks cold all day even in the hot sun. 

Closed cell foam is usually applied in 1-3 inch thicknesses.  It is used in crawl spaces to keep moisture off of the subfloor and out of the house and in 2x4 walls.  Closed cell foam also has the unique quality of adding to the structural rigidy of a home when applied to walls. Because it is denser than open cell and it uses a different agent to create bubbles, it is more expensive than open cell foam.   

Why use spray foam instead of batting or blown in?   

The main difference between foam and traditional insulations like batting and blown in insulation (cellulose or fiberglass) are significant.  

• Spray foam is an air barrier,  Batting and blown-in insulations are not.  If you've ever worn a loosely knit sweater, you know it isn't as effective as a parka. 
• Spray foam completely covers surfaces, similar to paint.  Batting is installed by cutting and fitting squares into the wall or ceiling cavities.  If you've ever felt a draft blow through an electrical switch or outlet on a cold night, you have experienced the limitations of batting.  It does not cover 100% and anywhere there is no coverage, the R-value is zero.  Gaps are why the effective R-value for a ceiling with R-30 insulation is closer to R-20.  
• Spray foam does not degrade with age.  Blown-in insulation and batting both degrade with age because they settle, collapse or are moved.  Batting under homes collapses because the little coat-hanger like stays rust and fail.  In many crawlspaces, the batting streams down like icicles because moisture weighs it down.  Spray Foam will last the life of your home. 
• Batting and blown-in insulation can harbor insects, birds and critters. It is a pretty natural nesting material.  Spray foam is solid and closed cell foam used in crawl spaces is too stiff for critters to break through or nest in. 
• Spray foam covers gaps and cracks, making it nearly impossible for small insects to enter your home. 

You don't have to break the bank to insulate your home in the Hilton Head Island, SC area. Learn more about using open cell foam for insulation by calling 843-540-3401 now.