Great Stuff 99108860 Smart Dispenser Big Gap Filler, Cream

Why it's worth it

Great Stuff's high-expansion foam with the Smart Dispenser straw, sold as a single can. It fills voids up to 3 inches and stops flowing the moment you let go, which makes it the least frustrating straw can for a one-weekend draft hunt.

This one expands hard, and that's both the point and the risk. Bob Vila's published review reports it swelling to roughly three times its dispensed volume, ahead of rivals on gaps over an inch. That's exactly what you want in a rim joist bay or a hole through a block wall. It's exactly what you don't want anywhere near a window jamb, where the pressure can bow the frame.

The Smart Dispenser straw is the real upgrade over the old design. There's no tip to cut and no drip when you pause — foam stops when you stop. Great Stuff rates the can as reusable for up to 30 days, and in practice you'll get a second session out of it if you clear the tip. It sticks to wood, drywall, metal, masonry, glass and most plastics.

From our review of 7 spray foam insulation cans, by David Sinclair, Managing Editor

What we like

• +This one expands hard, and that's both the point and the risk
• +The Smart Dispenser straw is the real upgrade over the old design
• +For a single can, you're getting the same chemistry the pros use without buying a tool first

What to know

• –Overhead work is rough
• –The expansion also means you should underfill on purpose
• –It's cream-colored and it yellows in sunlight, so outdoor joints need paint or trim over them