How Much Does Spray Foam Insulation Cost?
One of the top questions that we get asked is “How much does spray foam cost?” The cost of spray foam insulation generally ranges from $1.20-$2.50/ board foot. If that seems like a big range to you, that is because it is. Below is an explanation of what that means and the five leading factors, that influence spray foam price. The example pricing is actual pricing to give you an idea of how much your project will cost. Please note that this is intended as a guide, the most accurate way to get a price is to contact us.
One term that you will hear talked about is “Board Foot” This is the unit of measurement that our estimators use when pricing most jobs. One board foot is 1’ x 1’ x 1” of foam. Example: if you have a wall that is 10 feet by 10 feet, and want 1” of foam (not recommended) that wall would be 100 BF (Board feet). Now if you put 3.5” of foam in it, it would be 350 BF. When figuring Board Feet, we do not take out for stud width, but we do generally take out for windows and doors. The “board foot” price is not the end all, be all when it comes to pricing, but it is a starting point. Here Five things that we consider when pricing a job.
Size of Job
If we can set up our equipment one time for a few days, we will be able to install at a lower board foot price than if we have to drive to several different job sites. We have done some large houses (2500+ square foot) for $20-30000 and been able to get our board foot pricing down to under $1.30 per board foot. Compare this to a rim joist that takes us 3-4 hours with equipment warm up, spraying, and travel time, that could cost between $1500-$3000 and only use a few hundred board feet of foam.
The difficulty of the Job
Let's compare two crawl spaces at hunting camps, both 20’x30’, and 3” of foam. One is elevated 4 feet over a concrete slab, and the other is 2 feet above muddy ground. The one over concrete, we could spray for about $2800 (1.55/bf) but the muddy one, we might charge $3330 (1.85/bf) This is because it will take us much longer, and is much harder on our equipment.
How far away the job is
Take an attic in the same 20’ x 30’ hunting camp. We will be spraying against the roof deck, and leave out the gable ends just to keep the math simple. When you factor in the slope of the roof, we will say there is 700 square feet, At 5.5” (R-38), This would be 3850 board feet. If this job was in Binghamton NY, we have about an hour total of travel time and would be able to do a job like this for about $5500. If the same job was in Syracuse NY (about 3 hours of travel time) We would have to bill closer to $6000 on the same job.
Excessive foam usage
If we are bidding a house that has a stacked stone foundation, we know from experience that it will take an extra inch of material to equal the desired depth. Take a rectangle house 26’x40’ no windows and doors (to make math easy) 8’ tall walls, and 8’ tall basement. To do the first floor of that house with 3” of foam it would cost about $ 4500. If that house had a stacked stone foundation, it would also cost about $4500 to do 2” in the basement.
Retrofit vs New building
We have done some retrofit work where people have wanted rim joists sprayed in finished basements, or had flooring and ceiling in before walls were ready for insulating. These tend to be harder to bid, and would probably require scheduling a call with an estimator to get pricing.