The first question our clients ask us as a spray foam insulation contractor is “How much does spray foam insulation cost?” The answer is simple if you know the math behind the figures. Spray foam also referred to as Sprayfoam is normally calculated by a volume called the Board Foot which is 12″ Wide x 12″ Long x 1″ Thick.
The next part of the equation is based on the desired foam qualities and desired thickness which will determine the R-Value. There are two types of spray foam insulation commonly used, “Open Cell” and “Closed Cell“. These foams have different densities (contributing to R-value) and water repelling qualities. Quick examples are; Closed Cell can be used in below grade environments or where contact with water is likely/possible, i.e. basement or where high R-value is needed in a min thickness. Open Cell insulation is great in areas not exposed to moisture and where thickness is not an issue i.e. 2×4 framing and thicker for walls and 2×8 and thicker in an attic or roof assembly.
So after figuring out what type of foam is called for and the thickness needed for a desired R-Value we’re ready to figure out the volume. A quick example would be a 10′ wide wall(W) that stands 8′ tall(L) which has a cavity to be sprayed at 3-1/2” Thick(T) or 10 x 8 x 3.5 = 280 Bd Ft (board feet). We then need to multiply this number by the installed cost of the material per board foot. This number (based on Nov-12 prices) ranges from $0.45 – $0.60 per board foot for “Open Cell” and is based on the amount of prep, waste, trimming, hard to reach places, and other influencing factors. Closed Cell is priced anywhere between $0.98 – $2.00 a Bd Ft depending how confined the space is, i.e., a crawlspace, under a porch, the outside of a foundation wall, as well as the previously mentioned influences. There are other factors that can play into a quoted price like the size of the project. A small project may be on the higher side of the spectrum while a larger project on the lower. Some sprayfoam insulation contractors in the Chicago market have minimum charges.
We hope that this information is helpful in applying a general budget to your upcoming project. If you have any questions, please “Contact Us”