GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Audio Play Icon Headphones Icon Plus Icon Minus Icon Check Icon Print Icon Picture icon Single Arrow Icon Double Arrow Icon Hamburger Icon TV Icon Close Icon Sorted Hamburger/Search Icon

Community and Q&A

Closed or open cell foam?

Brian Lengel | Posted in General Questions on

Is Great Stuff (in the can from Lowe’s or Home Depot) open or closed cell foam? A google search said closed cell but I recall a GBA article on adding water vapor increases it’s expansion during curing so that implies open cell, doesn’t it? Thanks. (brand new to GBA subscription). Brian Lengel, Austin, TX

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. User avatar GBA Editor
    Martin Holladay | | #1

    To the best of my knowledge, many moisture-cured one-component spray foams (including Great Stuff) are closed-cell when fully cured.

    Here is a link to a document that declares that at least one Great Stuff product -- a canned spray foam called Great Stuff Pond and Stone Filler -- is both moisture-cured and closed-cell: Great Stuff Pond and Stone Filler.

    I don't think the fact that a foam produce is moisture-cured has anything to do with whether or not the cured foam is open-cell or closed-cell.

  2. Brian P | | #2

    Some advice, the cans with a straw aren't that easy to use. It's absolutely worth getting a dispensing gun for anything more than very small projects:

  3. Brian Lengel | | #3

    Thanks. I wish I could find the GBA article about can spray foams because I do not understand the economics:
    The foam dispensing gun costs $49.95. The 24 oz of Great Stuff PRO costs $12.47. Half as much, the 12 oz can with the straw, costs $4.25....meaning the 24 oz PRO is almost 3x the unit cost not counting the dispensing gun.
    I've became very adept at using (being a DIYer) of using drip irrigation tubing in lieu of the straw (must wire it at the nozzle tho) so as to get the can upside down in every circumstance. Alternatively, with foresight, a straw nozzle fits nicely into some 3/8" OD potable water white tubing (caulk applied to "glue" the arrangement so the straw won't 'blow out' under pressure). One has to be careful about application of the foam, of course, and not merely window dress it like paint...the nozzle end needs to get into/inside the crack and crevices and holes.
    What am I missing here? Seems like the cheaper way is can way, especially before the big box stores increased the 12 oz price by a dollar. Granted, more cans to waste but I recycle those.

  4. User avatar GBA Editor
    Martin Holladay | | #4

    I'm with you. My $99 gun got irreparably clogged. I went back to the $4 cans from the hardware store.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |