is spray foam moisture proof?

My main question is more or less is it mildew resistant?
I would like to use a product like great stuff to fill in a SMALL gap line in my foundation where the block meets the slab. I can not get a caulk gun in there to fill it and the little plastic hose that comes with the great stuff cans would be perfect to get in there and semi fill it before sheet rock goes up.

It wont be holding back intrusive water as far as i can tell since i already tore those parts up and repaired PLUS i still will be doing more repairs outside to stop any intrusion of water. This idea is more piece of mind then anything else.

thanks
tried googling but got no true answer and I just dont have a can I can read at the moment

 

Not something I'd use....though I don't know if it is mold resistant.

Why not just tape a flexible straw (or 4 or 5), or a length of flexible tubing to your caulking gun nozzle?

 

Closed cell spray foam will not allow water to flow through it. It becomes a vapor retarder at a thickness of 2 inches or more. I know one manufacturer sells an anti-microbial version of their foam. It is to prevent surface growth of mold on the foam itself. I don't get the impression that the mold eats the foam.

I think the most important thing in this situation is that if there is enough moisture for mold grow on the foam, then you have a larger problem on your hands and will have mold growing everywhere else behind the wall.

 

i am only looking to fill a thin gap line between my slab and wall. There does not appear to be any moisture or mold since there is also a horizontal 2x3 runner right there that is in like new condition (but probably about 20 years old). There was some rot on part of it which i was able to cut out and repairs the problem areas but i just wanted something to fill the gap since im puttting sheetrock back up. More or less i want something simple where the nozzle will fit through the tiny gap and keep LOW moisture and critters from getting in.

was able to find this this morning
Prevent Mold with GREAT STUFF?| Ice Dam Solutions

 

because i would not be able to get anything in there (like my finger) to press and seal the caulk. Spray foam is SUPER stick and will expand and seal on its own.

 

If the gap is fairly large I would use hydraulic cement rather than foam as that will hold much better that any foam ever will. I have also heard that insects will tunnel through some types of foam but will never try that with cement. Small cracks any kind of caulk or foam will do but big cracks no not unless you will use it in the center only and then fill it with cement.