How can I fix this hole in the wall?

[googlealchemist]

There is a backdrop to our wood stove...some sort of concrete panel that had tiles on it. The tiles all fell or got ripped off (we are putting up sheet metal instead for a heat shield) but as shown in the picture there is a large chunk of the wall where the panel and the old drywall behind it has just been destroyed.

I'm not sure how to address this, it's odd in shape and way bigger than just some little hole I can throw some filler into. And it's partially behind where the old panel is vs just all straight exposed drywall. There is a draft there and exposed insulation so it's not good either way.

Thanks for any advice.

 

[hj]

If you are putting up sheet metal, just cover it up.

 

[Sponsor]

 

[Reach4]

Put piece of wood (longer than hole) behind, and attach with screws through intact wall on two ends. If you cannot screw, maybe glue on one end would be sufficent, but screw the other end. Cut cement board or whatever to shape. Use drywall screw to attach the cement board, through a clearance hole, to the stick. Fill gaps somehow, maybe plaster or whatever. Put up your steel.

Alternative is to get metal lath back there and across hole. Apply plaster. I don't know the right plaster.

I am not a pro.

 

[Jadnashua]

I'd probably cut a bit more out until I had access to the studs which will give you something easier to attach new backing. You'd want to cut the material half-way across the stud so it was attached, and the patch can be screwed in.

To help support the upper edge and maybe the lower one, you could screw a slat on the back side of the existing material that would give you some support to then attach the new patch to on the horizontal sections as well.

A draft implies either the lack of a house wrap, or a very poorly installed one, and something you should budget for to resolve long-term as it will save you a lot of money and improve comfort considerably. FWIW, packing in some cellulose or rock wool insulation in the wall will also work better at stopping air than fiberglass, which acts more like a big air filter unless things are air sealed well.

 

[Dana]

I'd probably cut a bit more out until I had access to the studs which will give you something easier to attach new backing. You'd want to cut the material half-way across the stud so it was attached, and the patch can be screwed in.

To help support the upper edge and maybe the lower one, you could screw a slat on the back side of the existing material that would give you some support to then attach the new patch to on the horizontal sections as well.

A draft implies either the lack of a house wrap, or a very poorly installed one, and something you should budget for to resolve long-term as it will save you a lot of money and improve comfort considerably. FWIW, packing in some cellulose or rock wool insulation in the wall will also work better at stopping air than fiberglass, which acts more like a big air filter unless things are air sealed well.

+1 on the cutting out enough to make a stud-supported air-tight patch!

High density fiberglass like R15s (for 2x4) or R21s (for 2x6) are as air retardent as rock wool, but not as air retardent as cellulose.

If replacing the insulation, in this location rock wool would be the preferred material since it's extremely fireproof. Fiberglass will melt at surprisingly low temperatures, and when subjected to very high temperatures over time the fire retardents in cellulose dissipate.

 

[googlealchemist]

Thanks guys
I think I'll stuff some rock wool in there or just spray foam to squash draft then put the sheet metal over it to visually cover the mess.
The kitchen it's in needs a total revamping anyways so I figure I'm not going to waste time/money over it.