How to shoot foam into this gap.

[Aaron Fude]

Hi,

In the following picture, you are looking at a gap between my roof (with a skylight) and an interior stone wall (which used to be exterior before the addition). The roof structure is old and the roof shingles were recently installed by a fantastic roofing company. There are no leaks of any kind so that's not a worry.

However, there is lots of cold air coming through that gap. So I would like to shoot some foam into that space. But how can I do it and make sure that it sticks and also, how do I make sure that I don't muck up the stone that I am leaving explosed. That beam that's runs along the stone looks like a 2x8 so I want to shoot the foam 7 1/2 inches high. I can just see the stuff you buy at HD in cans falling out and messing up the stones and not really insulating all that well. (Maybe I can put a longer attachment that will place it deaper?) Anyway, I'm looking for advice on how to deal with it.

Many thank in advance,

Aaron

[ransley]

To me the stone looks rough, dirty with mortar on it. A chisel will remove mortar, Muriatic acid will clean it. For foam sheet plastic ductaped under the opening to keep foam off then cut it. Foam cans need to be upside down, to just extend the hose it will come out real slow or almost not at all. If I remember I slipped a bigger hose over the cans hose and heated the can in hot water to get it out. it expands so its hard to control.

[aemeijers]

If air is coming through the crack, sounds like the top edge of the roof and the stone wall was not flashed and sealed properly. Did they cut a notch in the stone and use overlapping flashing (2 interlocked L shapes?) If water isn't coming in, but air is, I'd try shoving fiberglass up there with a stick, and maybe finish with some of that plastic foam rope caulk, AKA backer rod, that they sell for driveway cracks, to provide a tight seal at the bottom. Foam in a can would likely make a mess, with a less-than-experienced user. A commercial foam gun with an experienced operator could probably do it, but unless you have other work on site for him, would be rather expensive.

-- aem sends...

[hallerb]

one MUST work carefully around chimneys lest heat transfer cause a housefire.

a old friend insulated great, had a fire caused by his insulation:(

One needs code enforcement officer info before proceeding

[DanG]

Aaron, this it the approach I would take:

Get some this visqueen with tape to cover your entire wall face, just in case. "

"Get a long enough one to cover your wall.

Buy, borrow, one of these:

similar. The last one I bought was about $40. Make sure you buy minimum expanding (little or no pressure/expansion) foam You can add a length of clear plastic tubing to the tip to get back in farther if you need to.

I'm glad you made me look - they have a foam that is already black and doesn't require painting, even outdoors, that I didn't know about:

and a can of cleaner for the gun if you intend to keep it for other work. If you don't clean the gun, throw it away - there is no other way to salvage the gun. Buy several cans of foam, especially if you can return what you don't use. Just looking I would guess at 6 cans from what I see in the picture.

Once the foam is set up - next day- saw any excess foam off with a serrated knife, Sawzall, hacksaw blade or similar. I would paint it flat black to loose in the shadow line. Forget this one if you use the black stuff.

They have a new fire version also:

[Aaron Fude]

Thanks!

Is there a retailer that sells touch n seal products?

[ds549]

i stapled some thin strips along the gap to cover it, drilled some holes in the strips and shot the foam in thru the little holes i drilled .this worked well for me. after cured you could remove the strips or leave them there. some strips on the outside can be used if you want to control the mess..

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[Jimw]

They sell a round foam "rope" in many sizes. It's designed to fill gaps like yours prior to calking. Buy several sizes and push it into the gaps according to the size of the gap. Then use some clear silicone caulk along the edges and any gaps to seal it. The clear caulk will not hurt the look of the stone, and the rope will be inside the gap. This rope is usually gray, so it will look like mortar. Ace Hardware sells this rope, and probably other places.

[Steve Barker]

the canned stuff works just fine. As a matter of fact the off brand stuff in the green can at walmart works better than the named brand (great stuff). and is a dollar cheaper. Two cans will do what you have there. Contrary to what one moron said here, the can does NOT have to be upside down. They work equally well in any position.

steve