SmartInsulationCalculator

Buying Guides

Best DIY Spray Foam Kits of 2026

Two-part kits give you contractor-grade closed-cell foam without the rig. They are unforgiving about temperature and technique, so match the kit to the job before you buy.

Updated January 2026 · about 7 min read

Popular picks on Amazon

As an Amazon Associate we earn from qualifying purchases. Product links on this page may earn us a commission at no extra cost to you.

Sizing the kit

Board feet = square feet × inches of thickness. Rim joists in an average basement need about 150–250 board feet at 2 inches. A 1,000 sq ft crawl wall area at 2 inches needs 2,000 board feet — at that scale get quotes from a contractor before buying kits.

Add 15–20% to whatever you calculate. Advertised yields assume perfect conditions.

Temperature is the whole game

Most kits want tank and substrate at 70–80°F. Cold tanks give poor yield and off-ratio foam that stays sticky. Store kits indoors overnight before use and warm the space if needed.

Gear for this job

Great Stuff Gaps and Cracks Insulating Foam Sealant,12 Ounce - Case of 12

Great Stuff Gaps and Cracks Insulating Foam Sealant,12 Ounce - Case of 12

Check price on Amazon

BEEST FullStop Spray Foam Insulation Kit - 240 Board ft/sq.ft. Fire Rated Spray Insulation Foam for Walls & Attics with Thermal & Soundproofing - Includes 12x Cans, 1 Cleaner, Pro X Gun, Safety Gear

BEEST FullStop Spray Foam Insulation Kit - 240 Board ft/sq.ft. Fire Rated Spray Insulation Foam for Walls & Attics with Thermal & Soundproofing - Includes 12x Cans, 1 Cleaner, Pro X Gun, Safety Gear

Check price on Amazon

BEEST FullStop Fire-Rated Spray Foam Insulation for Walls & Attics - 240 Board ft/sq.ft - High Density Expanding Spray Insulation Foam Sealant for Thermal & Soundproofing - 12 Pack (12x26.8 oz)

BEEST FullStop Fire-Rated Spray Foam Insulation for Walls & Attics - 240 Board ft/sq.ft - High Density Expanding Spray Insulation Foam Sealant for Thermal & Soundproofing - 12 Pack (12x26.8 oz)

Check price on Amazon

Magic Chems Spray Foam Insulation, Expanding Sealant, 2 Pack-25.4 oz | Closed Cell; High Density; Covers up to 40 sq ft; Cans Only, No Gun Included

Magic Chems Spray Foam Insulation, Expanding Sealant, 2 Pack-25.4 oz | Closed Cell; High Density; Covers up to 40 sq ft; Cans Only, No Gun Included

Check price on Amazon

As an Amazon Associate we earn from qualifying purchases. Product links on this page may earn us a commission at no extra cost to you.

Canned foam for the small stuff

For gaps, penetrations and window frames, single-component cans are the right tool. Use low-expansion around windows and doors, gaps-and-cracks formula for everything else, and a reusable foam gun if you'll be at it for more than one can.

Safety

Organic vapor respirator (a dust mask is not adequate), full skin coverage, goggles and ventilation. Keep everyone else out of the space during spraying and for the manufacturer's re-entry window.

Run the numbers

Spray Foam Board Feet CalculatorRim Joist Calculator

Frequently asked questions

How many board feet does a spray foam kit cover?
Kits are sold in 200, 600 and 1,000 board foot sizes; real yield typically lands 10–20% below the printed number.
Can I spray foam in cold weather?
Only if you warm the tanks and the surface to the manufacturer's range, usually around 70°F. Cold spraying wastes chemical and can cure badly.
Do I need a respirator for canned foam?
For small single cans, ventilation and gloves are usually adequate; for any two-part kit, a fitted organic vapor respirator is required.

Insulation gear worth owning

The tools and materials that show up on almost every insulation job.

BEEST FullStop Spray Foam Insulation Kit - 240 Board ft/sq.ft. Fire Rated Spray Insulation Foam for Walls & Attics with Thermal & Soundproofing - Includes 12x Cans, 1 Cleaner, Pro X Gun, Safety Gear

BEEST FullStop Spray Foam Insulation Kit - 240 Board ft/sq.ft. Fire Rated Spray Insulation Foam for Walls & Attics with Thermal & Soundproofing - Includes 12x Cans, 1 Cleaner, Pro X Gun, Safety Gear

Check price on Amazon

Great Stuff Gaps and Cracks Insulating Foam Sealant,12 Ounce - Case of 12

Great Stuff Gaps and Cracks Insulating Foam Sealant,12 Ounce - Case of 12

Check price on Amazon

Loctite Tite Foam Gaps & Cracks Spray Foam Sealant, 12 fl oz Can, 1 Pack - Polyurethane Expanding Insulation

Loctite Tite Foam Gaps & Cracks Spray Foam Sealant, 12 fl oz Can, 1 Pack - Polyurethane Expanding Insulation

Check price on Amazon

Respirator Mask with Filters set - Reusable Respirator Mask for Chemicals, Painting, Spraying, Epoxy Resin, Dust, DIY etc

Respirator Mask with Filters set - Reusable Respirator Mask for Chemicals, Painting, Spraying, Epoxy Resin, Dust, DIY etc

Check price on Amazon

As an Amazon Associate we earn from qualifying purchases. Product links on this page may earn us a commission at no extra cost to you.

Keep reading

Buying GuidesBest Insulation Blowers of 2026Rental machines vs owning a blower, hose length, hopper size and what to look for before you blow an attic yourself.Buying GuidesBest Radiant Barriers of 2026Perforated vs solid foil, single vs double sided, emissivity ratings and how to install radiant barrier so it keeps working.Buying GuidesBest Safety Gear for Insulation WorkRespirators, coveralls, gloves and eye protection for fiberglass, cellulose and spray foam — what rating you need for each material.Buying GuidesBest Thermal Leak Detectors of 2026Spot thermometers, thermal leak detectors and phone-attachment IR cameras compared for finding missing insulation and drafts.