Need an expanding polyurethane foam spray to seal gaps, insulate, and block drafts? This guide highlights five top options, each suited to different projects—from large gap filling to precise door and window work. The selections help DIYers, homeowners, and professionals choose the right foam for indoor and outdoor use, with clear reasoning for why each is a good fit.
| Product | Best For | Key Benefit |
|---|---|---|
| Red Devil 0909 | Large gaps and cracks | Versatile interior/exterior use |
| Great Stuff Smart Dispenser | Fast, clean gaps | No-drip, easier application |
| Kraken Bond 2x12oz | Cold climates, controlled fill | Moisture-curing with straw |
| Stanley F905 | Windows, doors, penetrations | Low expansion for tight spaces |
| Akfix 805 2×12 Oz | Penetrations and large gaps | Ozone-friendly formula |
Note: Each product has unique handling and cure times. Always follows manufacturer instructions for ventilation, PPE, and cleanup to ensure a safe, effective seal.
Red Devil 0909 Spray Foam
Brand: Red Devil | 12 oz | Off White
- Fills large holes, gaps, and cracks to prevent drafts.
- Indoor or outdoor use, offering versatile application around the home.
- Sandable, paintable, and stainable after curing for a seamless finish.
Best for: Home projects needing substantial gap filling around windows, eaves, or exterior penetrations. Choose this if you expect a robust, paintable seal and plan to finish the surface.
Caution: Heavier expansion can lead to overfilling if not controlled; apply in layers and trim excess after curing.
Great Stuff 99108824 Smart Dispenser
Brand: Great Stuff | 12 oz | Cream
- Gaps and cracks attack with reduced drafts and energy loss.
- No-drip formula helps prevent mess and wasted product.
- Foam stops where you stop, aiding cleaner application.
Best for: Quick, clean sealing of medium to small gaps; ideal for DIYers who want straightforward application with limited cleanup.
Caution: The nozzle can sputter if held too close; apply in steady, controlled motions for best results.
Kraken Bond Gaps & Cracks (2x12oz)
Brand: KRAKEN BOND | 2×12 oz | Straw Use
- Easy dispensing with straw adapter; moisture-curing one-component foam.
- UL certified for safety and reliability; designed for window and door gaps.
- Best results at about 68°F; works in 41°F to 86°F with acclimation in cold climates.
Best for: Controlled fills around windows and doors where you want reliable, safe expansion and good adhesion. Choose this if you value temperature guidance and UL certification.
Caution: Let the can acclimate to room temperature in cold weather to maintain performance.
Stanley F905 Gaps & Cracks Sealant
Brand: STANLEY | 12 oz | One Pack
- Versatile foam for gaps up to 3 inches wide; designed for DIYers and pros.
- Waterproof and weather-ready to protect against air and moisture.
- Straw dispenser enables precise targeting in tight spaces with low expansion.
Best for: Window and door systems or penetrations where tight control and waterproof performance matter. Avoid overly large fills if you need minimal expansion.
Caution: Low expansion means multiple applications may be needed for larger gaps; plan for staged fills.
Akfix 805 Gap Filler (2×12 Oz)
Brand: Akfix | 2×12 oz | Pack
- Single-component, moisture-curing and self-expanding foam with straw dispensing.
- Suitable for windows, doors, big gaps, joints, cavities, and penetrations.
- Dries rigid and can be trimmed, shaped, and sanded after curing.
Best for: Broad gap filling with accessibility to various tight areas; choose this for ozone-friendly formulation and flexible use around structures.
Caution: Requires protective gloves and eyewear during application; ensure proper ventilation and allow full cure time for best results.
Buying Guide
What should I look for when selecting expanding foam?
- Expansion rate: High expansion is good for large gaps; low expansion helps in tight spaces near frames.
- Temperature range: Some formulas perform best around room temperature; check recommended use temperatures.
- Application method: Straw dispensers aid precision; nozzles or straws affect reach in tight areas.
- Cure and finish: Sandable, paintable, or stainable foams simplify final finishes; consider surface goals.
Indoor vs outdoor use
Outdoor foams should resist moisture and UV exposure; indoor foams should be safe for occupied spaces and offer smoother finishes.
Safety and preparation
Wear protective gear, work in well-ventilated areas, and follow can instructions for venting and cleanup. Some products require trimming after curing, while others can be painted or stained immediately after curing.
FAQ
- What is expanding foam used for? It seals gaps, prevents drafts, and improves energy efficiency by filling cracks around windows, doors, pipes, and penetrations.
- Can I paint expanding foam? Yes, many foams are sandable, paintable, or stainable after curing; check product data for compatibility.
- Do all expanding foams work indoors and outdoors? Some are designed for both environments; select a formula rated for the intended conditions.
- How do I avoid overexpansion? Use low expansion foams for tight spots and apply in thin layers; allow curing between applications if needed.
- Is it safe to use around electrical outlets? Yes, but follow safety guidelines and ensure the foam does not interfere with electrical components.
- What temperature should I use expanding foam? Most foams perform best at room temperature; extreme cold or heat can affect cure and performance.