Spray foam is sold in board feet: one square foot, one inch thick. Enter area and depth to get kits.
How it works
Area × depth in inches gives board feet. Adds 10% for yield loss, then divides by kit yield.
Before you order
- Warm chemical tanks and the surface to the temperature on the label, since cold kits yield far less.
- Spray closed-cell in passes no thicker than the product allows.
- Foam in occupied spaces usually needs a thermal or ignition barrier, so check local code.
Common questions
What is a board foot of spray foam?
One square foot at one inch thick. A 600 board foot kit covers 300 sq ft at 2 in, in ideal conditions.
Open cell or closed cell?
Closed cell gives about R-6 to R-7 per inch and resists moisture. Open cell is about R-3.6 per inch and costs less per inch.