When it comes to insulation, one of the first questions is: How much do I actually need? The answer depends on the size of your project and the type of product you’re using. Let’s break down the basics so you can make the most cost-effective choice.
How to Calculate Spray Foam Insulation Needs
Calculating how much spray foam insulation you need for a project is pretty straightforward: Measure your project in board feet (square feet × thickness in inches).
Once you know how much spray foam insulation is required, you can choose the option that best fits your project.
2K Kits Vs. Canned Spray Foam Insulation
Two-component kits, often called 2K kits, include two pressurized tanks connected by hoses to a spray gun. When the components mix via the gun applicator, they expand into spray foam insulation.
2K kits are sized by coverage in board feet. One board foot equals 1 square foot sprayed at 1 inch thick. Common sizes include:
- 210 board feet (small kit)
- 650 board feet (large kit)
While they’re convenient for large, continuous projects, 2K kits can be tricky for smaller jobs. If you don’t use the whole kit in one go, the hoses and gun can seize up, leaving you with expensive leftover material that’s wasted.
Cost of 2K Kits
Here’s where things get real. 2K kits carry a hefty upfront cost:
Hidden costs also creep in, including:
- Unused foam that cures in the tanks
- Hoses that clog
- Partial kits that can’t be saved for later
Waste adds up fast, especially on small projects.
A Better Option for Small Jobs: Thermospray
Tytan Professional® Thermospray is a single-component, professional-grade spray foam packaged in individual cans—no hoses, no bulky equipment, no wasted material.
Thermospray shines in small to medium sized projects as well as in repairs where a full 2K kit would be overkill. For example:
- Filling around outlets in new builds
- Repairing insulation in existing walls
- Workshops, sheds, or garages
- In-home noise reduction
Individual cans and cases of Thermospray store well for over a year (when stored properly according to the TDS). So you can buy by the case and use as needed—without worrying about waste or 2k kit costs.
Calculating How Much Thermospray You Need
Each can of Thermospray covers about 21 board feet at 1 inch thickness. So to calculate how much you need for your project, figure out the number of board feet (see above) and divide by 21.
Keep reading to see an example of a real project with our board feet measurements and cost comparison analysis.
Thermospray Costs Less
Thermospray makes it easy to match your budget to your project size. For example, we insulated a backyard shed with Thermospray, and here is the project by the numbers.
Project size: 315 board feet (8×12 shed)
With 2k kits, we would have had to buy more than the project required.
Option 1: Two 210 kits (420 board feet)
- Cost: $914
- Waste: 105 board feet of insulation
Option 2: One 650 kit (650 board feet)
- Cost: $1,010
- Waste: 335 board feet of insulation
Option 3: 15 cans of Thermospray (21 board feet each)
- Cost: $300
- Waste: None
- Any leftover cans can be used later
In this real example, Thermospray cost about 70% less compared to 2K kits, with no waste leftover.
The Bottom Line
2K kits are great for large, one-and-done projects. But for small to mid-sized jobs, they often leave you paying for foam you can’t use. Thermospray, on the other hand, is cost-effective, flexible, and easy to use, making it the smarter choice when you don’t need a full kit.
So, when you’re asking yourself, “How much Thermospray do I need?” just calculate the project’s board feet, divide by 21, and stock up with confidence. For a job well done, choose Tytan Professional Thermospray.
