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Best Air Sealing Products of 2026

Air sealing supplies are the highest-return dollars in the whole insulation aisle. Here is what to buy for each kind of gap.

Updated January 2026 · about 6 min read

Popular picks on Amazon

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Canned foam

Gaps-and-cracks formula for penetrations up to 3 inches; low-expansion window and door formula around frames so you do not bow the jamb. A reusable dispensing gun pays for itself after two cans and lets you leave a can loaded for weeks.

Weatherstripping and door seals

Silicone or EPDM bulb seals last far longer than foam tape. Add an adjustable door sweep or a full threshold kit for exterior doors, and a garage-to-house door seal if the garage is attached.

Gear for this job

Holikme Weather Stripping Door Seal, Shower Door Seal Strip,1.8" W-33Feet | Flexible Door Seal, Seals Gaps up to 1.2", Helps Reduce Air Leaks & Dust, For Doors & Windows

Holikme Weather Stripping Door Seal, Shower Door Seal Strip,1.8" W-33Feet | Flexible Door Seal, Seals Gaps up to 1.2", Helps Reduce Air Leaks & Dust, For Doors & Windows

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Ninsula 33Ft Door Weather Stripping, (1/2in x 1/4in), Strong Adhesive, Sound Proof, Door Insulation, Weatherproof Foam Tape for Doors, Weatherstripping for Doors Frames, Windows

Ninsula 33Ft Door Weather Stripping, (1/2in x 1/4in), Strong Adhesive, Sound Proof, Door Insulation, Weatherproof Foam Tape for Doors, Weatherstripping for Doors Frames, Windows

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Ravinte Weather Stripping Door Seal, Q-Shaped Kerf Foam Strip, 26 FT, Black | Push-In Door Weather Stripping, No Adhesive, Fits 0.35 to 0.59 Inch Gaps, Door Frame and Jamb Seal, Blocks Drafts and Noise

Ravinte Weather Stripping Door Seal, Q-Shaped Kerf Foam Strip, 26 FT, Black | Push-In Door Weather Stripping, No Adhesive, Fits 0.35 to 0.59 Inch Gaps, Door Frame and Jamb Seal, Blocks Drafts and Noise

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VITAM AMO Weather Stripping Seal Strip for Doors/Windows 18 Feet, Self-Adhesive Backing Seals Large Gap (from 5/16 inch to 15/32 inch), Easy Cut to Size

VITAM AMO Weather Stripping Seal Strip for Doors/Windows 18 Feet, Self-Adhesive Backing Seals Large Gap (from 5/16 inch to 15/32 inch), Easy Cut to Size

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Small-gap products

Foam outlet and switch gaskets on exterior walls, fire-rated caulk at top plates, foil tape for duct joints (never cloth duct tape), and house wrap tape for sheathing seams and foam board joints.

Windows

Shrink-film kits are ugly but effective on single-pane windows — often a 10–15% cut in heat loss through that window for a few dollars. Rope caulk on sashes you do not open is another cheap seasonal fix.

Run the numbers

Energy Savings CalculatorHeat Loss (BTU) Calculator

Frequently asked questions

What is the cheapest way to reduce drafts?
Canned foam at attic and basement penetrations plus weatherstripping on exterior doors — usually under $150 for a whole house.
Is duct tape OK for sealing ducts?
No. Use foil tape or mastic; cloth duct tape dries out and fails within a few years.
Do outlet gaskets really help?
Individually they are small, but exterior-wall outlets are a common leak path and a pack of gaskets costs a few dollars.

Insulation gear worth owning

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

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

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Holikme Weather Stripping Door Seal, Shower Door Seal Strip,1.8" W-33Feet | Flexible Door Seal, Seals Gaps up to 1.2", Helps Reduce Air Leaks & Dust, For Doors & Windows

Holikme Weather Stripping Door Seal, Shower Door Seal Strip,1.8" W-33Feet | Flexible Door Seal, Seals Gaps up to 1.2", Helps Reduce Air Leaks & Dust, For Doors & Windows

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Outlet Insulation Foam Gaskets | 50 Pack Draft Sealers for Outlets & Switches | Fits Duplex, Toggle & Rocker Wall Plates | Ideal for Homes, Offices & Commercial Spaces

Outlet Insulation Foam Gaskets | 50 Pack Draft Sealers for Outlets & Switches | Fits Duplex, Toggle & Rocker Wall Plates | Ideal for Homes, Offices & Commercial Spaces

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Duck MAX Strength Window Insulation Kit, Winter Window Seal Kit Fits up to 5 Windows, Heavy Duty Shrink Film Cuts to Size for Easy Indoor Installation, Window Tape Included,62 In. x 210 In., Clear

Duck MAX Strength Window Insulation Kit, Winter Window Seal Kit Fits up to 5 Windows, Heavy Duty Shrink Film Cuts to Size for Easy Indoor Installation, Window Tape Included,62 In. x 210 In., Clear

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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.

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