Is Great Stuff Great?

[Steve B]

I need to use a bunch of this product this spring to patch up some holes in my cabin where the carpentryship wasn't exact. I notice they have two formulas, one expanding more than the other one.

Tips on usage appreciated.

In some places, the gap is up to an inch. Would I be better to poke shredded fiberglass in there using a dowel as a poker, then seal it with Great Stuff? Or even seal it with a nice shade of caulking? Or fill it mostly with Great Stuff, then smooth or cut smooth, then caulk over for a nice finish?

Probably going to use a couple of dozen cans in all. It depends on how much I fill up with shredded glass first, or just use the foam for the entire void. What would you do?

Steve

[Rick Brandt]

The big issues with "Great Stuff" are...

Wear gloves and clothes that you won't mind tossing when you're done. It is near impossible to get off of skin and even harder to get out of fabric. Do not be tempted to shape it like caulk. Let it harden and then "shave" excess off with a razor knife.

The power of the expanding foam CAN damage stuff. Be conservative. It can crack drywall and bow metal thresholds enough that the door rubs.

[DanG]

If you are really going to use large quantities, get into the commercial size stuff.

This system requires that you have cleaner for the gun. The advantage is that you do not use up the entire can. I buy the door and window product to avoid collateral damages. Triple expanding can be deadly depending on the situation.

[Bob M.]

Or crack windows if put in between window frames & studs. As was mentioned, don't shape the stuff. Wait until it dries, then cut it with a knife.

[SteveF]

There's three types - Cracks/Gaps in the red can, Big Gaps in the black can and Doors/Windows in the blue can.

I've found if you fill a big area with the Big Gaps stuff (2" x 5" x 22") it cures and then over the next couple of weeks shrinks and leaves an 1/8" -

1/4" gap all the way around. The Door/Windows version cures to a harder skin than the Cracks/Gaps plus doesn't push very hard against things so I've settled on that kind.

For air sealing, lay a bead down all the way in and let it expand. Put in less than you think you need until you get the hang of how much it expands. Put some insulation on top of that if you want after it cures.

For void filling, I've found the best bet is to fill as much as possible with a piece of XPS foam board (the pink stuff at Home Depot). Cut a piece so there is a 1/4" gap all the way around, put it in the gap and foam around it. Nothing magic about the 1/4" number - that's the size of the dispensing tube.

Comes off your skin easily with acetone. Of course, acetone isn't particularly good for you so wear thin gloves if you got 'em. My work clothes have paint, caulk and glue on them so I can't tell if I ever got any GS on it.

When in doubt, read the instructions on the can.

Steve.

If you are just going for air sealing

>

[Louis Geoffroy]

I will be giving a off-topic comment now:

To easily removing this product from you skin, Use baby powder before and after the use on your hand or part of skin it touch. It do work great.

Louis

[Steve Barker]

Brake or carb cleaner takes it right off also. (brake cleaner's a bit less harsh)

[Steve Barker]

One thing to remember, be prepared to use the whole can once you begin. You'll never come back to a partial can and have it work.

[SteveF]

Good point. Also, I've had a couple of cans that wouldn't work at all so buy a couple extra if you live 15 miles from the nearest hardware store like I do.

Steve.

[Steve B]

Yeah, I found a couple of partially used cans in the shed from the previous owner, and no way to get any more out of that spout. I figured getting it all ready and using whole cans start to finish. It is 7.2 miles down to the hardware store from my cabin, not bad. The next settlement is 30 miles from that store.

I'm ending up with a small hardware store up there, but every time I can go scrounge something and save a trip to town, I have to high five the nearest tree limb.

Steve

[Steve Barker]

Yes, and be sure to take them back eventually. There's no excuse for crap like that.

[LayPerson Tom]

imho:

Since this is just an option question, I dislike "great stuff" I've had much better results with the latex competitor. The stuff doesn't over expand, and cleans off clothes.

As for a finish, I've heard people tooling it(razor scraper) after it cures and painting the stuff.

BTW, for larger gaps you can use backer rod with caulk, instead of expanding foam.

tom @

[Rick Blaine]

I think you are talking about the DAP product. I've used both. The DAP latex material is a little softer and less dense than Great Stuff. Depending on what you plan to put on top of the foam (if anything), Great Stuff provides a slightly stronger base for material like plastic wood.

[LayPerson Tom]

imho:

I would use backer rod if you want to confine where you squirt the stuff. In the future you might want to check the expanding foam that is latex based. It cleans up with soap and water, and can be painted over.

Just thinking out loud....

tom @

[[Corncobb]158]

I think your choice of contractor is the bigger concern. But if you need 12 cans to fill something, I would suggest using the same material that is missing from this void in question.

[[Corncobb]158]

I've got a question for all of you guys. I mean everyone! Since I'm seeing many years of postings here, it may be a good place to start this topic! "The HomeDepot" is the spot light. How the great hardware chain goes from "how doers get it done to , how do we control the market so that we can absorb 70% out of all contractors pockets and still make them try and use this shipped in crap and call it professional!