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When sealing and insulating large cracks or openings, two names always rise to the top — Great Stuff Big Gap Filler and DAP Touch ’n Foam MaxFill.

When sealing and insulating large cracks or openings, two names always rise to the top — Great Stuff Big Gap Filler and DAP Touch ’n Foam MaxFill. Both products are designed to expand and fill big voids, providing a strong seal against air, moisture, and pests. But which one actually expands more and delivers the best results for your DIY project? Let’s find out.

Great Stuff Big Gap Filler – Powerful Expansion for Big Jobs

Great Stuff Big Gap Filler Insulating Foam Sealant is specifically formulated for filling larger openings and wide cracks up to 3 inches in diameter. Once applied, it expands to fill the entire cavity, sealing out air, moisture, and pests while adding a layer of insulation.

Its closed-cell formula creates a durable, airtight barrier that adheres to most building materials — including wood, metal, masonry, glass, and plastics. This makes it perfect for around plumbing penetrations, attic joints, rim joists, and garage framing.

The cured foam is firm, easy to trim, and can be painted or sanded after full curing. For the price of just $7.98, it delivers professional-grade expansion and coverage in a simple one-can solution.

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DAP Touch ’n Foam MaxFill – Maximum Expansion for Oversized Voids

DAP Touch ’n Foam MaxFill is one of the most powerful expanding foams on the market. Designed for the largest gaps and voids, this foam can expand up to three times its original size, completely sealing spaces that other standard foams struggle to fill.

Its unique polyurethane formulation provides superior adhesion and long-term durability, even in extreme temperature conditions. Once cured, MaxFill is water-resistant, helping prevent moisture infiltration, wood rot, and mold growth.

One of its biggest advantages is its high-density structure, which provides extra strength and rigidity once set. It’s ideal for exterior gaps, utility penetrations, rim joists, crawlspaces, and even gaps between framing where stability is crucial.

At $7.55, it’s a highly affordable option that delivers massive expansion and coverage, making it perfect for large, difficult-to-reach voids.

👉 Buy DAP Touch ’n Foam MaxFill on Amazon: https://amzn.to/4nwCkBi

Which One Expands More?

When it comes to pure expansion, DAP Touch ’n Foam MaxFill takes the lead. Its formula is engineered to expand up to 3× more than standard foams, making it better suited for filling oversized cracks and cavities where volume coverage is key.

However, Great Stuff Big Gap Filler still offers impressive expansion — ideal for gaps up to 3 inches — with slightly finer control during application. That means it’s easier to use for precision work, sealing around windows, pipes, or smaller areas without excessive overflow.

In short:

MaxFill = Maximum Expansion + Structural Strength
Big Gap Filler = Controlled Expansion + Clean Finish

Performance and Ease of Use

Both products are simple to use — just shake the can, attach the straw applicator, and spray. But their behavior once applied differs slightly.

Great Stuff Big Gap Filler cures into a medium-density foam that’s firm yet easy to trim and paint. It’s excellent for indoor and moderate outdoor use.

DAP MaxFill, on the other hand, cures into a denser, tougher foam that’s harder and more resistant to physical damage. It’s perfect for sealing exterior voids or heavy-duty construction areas where strength matters.

Both foams dry tack-free in about 15 minutes and fully cure within 8 hours, depending on temperature and humidity.

Final Verdict: Which One Should You Buy?

If your project involves massive voids, structural gaps, or outdoor conditions, go with DAP Touch ’n Foam MaxFill. Its extreme expansion and high density make it the best choice for demanding applications.

If you’re working on smaller or medium-sized gaps where clean finish and precision control are important, Great Stuff Big Gap Filler is unbeatable. It offers reliable expansion, easy trimming, and smooth results with minimal mess.

Both are affordable, easy to use, and deliver professional results — making them must-have tools for any DIYer or contractor.

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