Hi Jason, I just bought a house, and I have a fireplace that has been painted on the inside and out. Also it has been permanently sealed with expanding foam and foam board. I would like to open up the fireplace so it can be used again. Im wondering if I just cut the foam out and start a fire will i have a problem with the paint and leftover foam? Will that just burn off? - RM
Hi RM, Well, the previous owners were obviously not interested in using that fireplace, because they took some semi-permanant measures to decommission it. They are typical DIY mistakes really, but they will take some effort to undo. First of all, if you just rip out the foam and fire up some logs you are going to have some toxic off-gassing of the foam and paint. It is not going to be good, so you have to do your best to get that stuff stripped.
1) Cut the foam out. Do your best to cut out as much of the expandable foam. You will have to use a scraper and wire brush to get all of it off. The good thing is it looks like they used it over the area that was painted. If you get that Great Stuff foam into bare brick it soaks in deeply, and it is a nightmare to get off. The paint may have kept it from soaking into the brick pores. DO NOT try to burn the foam it off at all. The smoke from burning expandable foam can straight up kill you. No joke, it is bad news if you burn it.
2) Get that paint off the walls next. There is a gel paint strip called Lightning Strip. You will probably have to buy it online. I don't know of any chain store that sells it, since it is a specialty low vapor paint remover. Do not cut corners on this and get any old paint stripper. You are working in a tight space with this project, so you cant be using any old heavy vapor stripper. I have used Lightening Strip quite a bit to get latex paint off concrete and brick. You spray it on, and it releases the paint so you can scrape or scrub it off. Porous brick takes a few applications to get the paint out of the nooks and cranny's.
3) Now that you have it back to original, size it up for a Chimney Balloon. The reason the previous owner plugged it was because it was drafty. So get that thing plugged right with a Chimney Balloon. If I was to take a guess on size (just by the photo). I bet it takes a 24x12 Chimney Balloon, but go ahead and measure and pick a Chimney Balloon size from your measurements.
4) Before you have your first fire have the chimney inspected by a CSIA chimney sweep. Make sure they do a level 2 inspection that includes fishing a camera down the flue to see how the flue liner or flue tile look. If they say you need a new liner get an inspection report with photos and have it quotes by 3 contractors.
RM, I'm sure you were hoping I would say: "Rip out the foam board and fire up the logs!" but that would be dangerous solution for many reasons. Painting and foaming up a fireplace interior are very common mistakes well meaning homeowners make, and it takes some work to undo. But if you follow these steps you can have a usable fireplace and still have it sealed tightly in the off-season. - Jason