Spray Foam Cost Calculator – Board Feet, Price & Coverage Estimate
Estimate the cost of spray foam insulation based on area, thickness, and foam type. Compare open cell vs closed cell spray foam pricing per board foot.
Spray Foam Cost Calculator Formula
Board Feet = Area x Thickness; Cost = Board Feet x Price per BF
How to Calculate Spray Foam Cost
- 1. Calculate board feet: Board Feet = Area (sq ft) x Thickness (inches)
- 2. Determine price per board foot: Open cell = $0.44/BF, Closed cell = $1.50/BF
- 3. Total cost = Board Feet x Price per board foot
- 4. Coverage = total area in sq ft at the specified thickness
Example Calculation
Let's say you're insulating a 1,500 sq ft area with 3 inches of open cell spray foam.
- area: 1500
- thickness: 3
- foamType: open_cell
Board feet: 4,500 BF, estimated cost: $1,980.00, coverage: 1,500 sq ft
Tips
- Open cell spray foam is best for interior walls and soundproofing — it expands to fill cavities completely
- Closed cell spray foam provides a moisture barrier and higher R-value per inch — ideal for basements and exterior walls
- Board feet is the standard unit for spray foam measurement: 1 board foot = 1 sq ft at 1 inch thick
- Get at least 3 quotes from licensed installers — labor can significantly affect the final price
Frequently Asked Questions
How much does spray foam insulation cost per board foot?
Open cell spray foam costs approximately $0.44 per board foot, while closed cell costs about $1.50 per board foot. A board foot equals 1 square foot at 1 inch of thickness.
What is the difference between open cell and closed cell spray foam?
Open cell foam is softer, more affordable, and great for sound dampening with an R-value of about R-3.7/inch. Closed cell foam is denser, acts as a moisture barrier, and offers R-6.5/inch but costs significantly more.
How many board feet do I need for a 2,000 sq ft house?
It depends on the thickness. For 3 inches of foam on 2,000 sq ft, you need 6,000 board feet. At open cell rates that is about $2,640 and at closed cell rates about $9,000.
Is spray foam worth the cost?
Spray foam has a higher upfront cost than traditional insulation but provides superior air sealing, moisture control, and long-term energy savings. Most homeowners recoup the cost within 5-7 years through reduced energy bills.