Home & DIY

Spray Foam Insulation Cost Calculator

Board feet, sets and installed cost for open or closed cell.

Enter your values

Results update instantly as you type — no submit needed.

Results
Installed cost
$8,769.23
Board feet
7,015
Thickness needed
5.85 in
Cost per sq ft
$7.31
DIY kits (600 bf)
12

Quick answer

Spray foam is priced per board foot (1 sq ft at 1 in thick); open cell runs about $0.45–0.75 and closed cell $1.00–1.50 per board foot installed.

board feet = area × thickness (in)

At a glance

What it doesBoard feet, sets and installed cost for open or closed cell.
CategoryHome & DIY
Inputs neededArea to insulate, Foam type, Target R-value, Price per board foot
Main outputInstalled cost
Formulaboard feet = area × thickness (in)
CostFree — no sign-up, no download

How to use the Spray Foam Insulation Cost Calculator

  1. 1Enter the square footage of wall, roof deck or crawl space.
  2. 2Choose open or closed cell foam.
  3. 3Set your target R-value and local price per board foot.

Inputs explained

Area to insulate(sq ft)
Enter the area to insulate you are working with.
Foam type
Choose one of: Open cell (R-3.7/in), Closed cell (R-6.5/in).
Target R-value(R)
Enter the target r-value you are working with.
Price per board foot($)
Enter the price per board foot you are working with.

Worked example

Using the values the calculator loads with:

Inputs

  • Area to insulate1200 sq ft
  • Foam typeClosed cell (R-6.5/in)
  • Target R-value38 R
  • Price per board foot1.25 $

Results

  • Installed cost$8,769.23
  • Board feet7,015
  • Thickness needed5.85 in
  • Cost per sq ft$7.31
  • DIY kits (600 bf)12

Frequently asked questions

What is a board foot of spray foam?

One square foot sprayed one inch thick — the standard unit foam contractors quote on.

Is closed cell worth the extra cost?

In crawl spaces, rim joists and roof decks yes: it adds a vapour barrier and nearly double the R per inch.

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.