Welding backer inside house

[BMan2005]

I’m going to be welding up 1/4” plate in the room of our house. House is under construction and bare cement floors. My question is, what is the best thing to use against the walls between the 1/4” plate and wood stud walls for one prevention of fire welding on the plate against the studs, two fire insulation from outside the room.

I was thinking blanket rock wool sheets, then I read it’s advised to keep away from direct heat. Same for Sheetrock that I know a lot of retail store safes use.
My last idea is sone type of cement board? I could fasten it to the walls and ceiling and lay the plate to it and weld up. Ideas?

 

[Rustyiron]

Is this for a regular welding area?
Are welding sparks your only concern?
18ga sheet metal is enough protection from welding sparks.
I'd kinda be concerned about trying to cover wood framing to the point where you can't visibly check for something smoldering or douse it with water. I'd come down the wall with sheet metal with a 90* bend at the bottom that turned into the room 1-2" then just lay your 1/4" sheet over it at the floor/wall.
Overall, it would take a crazy amount of welding or grinding sparks to set the framing on fire.
Maybe I'm not understanding what you are doing.

 

[Topzide]

I would use drywall with a cement board on top of it. Just like a safe with the steel, then drywall inside. JM2C.

 

[BMan2005]

Is this for a regular welding area?
Are welding sparks your only concern?
18ga sheet metal is enough protection from welding sparks.
I'd kinda be concerned about trying to cover wood framing to the point where you can't visibly check for something smoldering or douse it with water. I'd come down the wall with sheet metal with a 90* bend at the bottom that turned into the room 1-2" then just lay your 1/4" sheet over it at the floor/wall.
Overall, it would take a crazy amount of welding or grinding sparks to set the framing on fire.
Maybe I'm not understanding what you are doing.

No this is for a gun room/vault. It will be 1/4 plate but to weld it I need something fire proof between the steel and wood stud walls

 

[BMan2005]

I would use drywall with a cement board on top of it. Just like a safe with the steel, then drywall inside. JM2C.

You think drywall then Cement board wound be best? Or two layers of cement board instead?

 

[Hay Dude]

I used cement board when I had to weld a beam across lally column poles and had a fireman stand by with garden hose

 

[Topzide]

Cement board is providing the fire and heat protection from the welding. The drywall will act as a fire buffer if you house caught fire. Have you tried to burn drywall? The paper goes up, but the drywall just glows. We used to build townhouses that had two 1" drywall layers between units!

 

[BMan2005]

Cement board is providing the fire and heat protection from the welding. The drywall will act as a fire buffer if you house caught fire. Have you tried to burn drywall? The paper goes up, but the drywall just glows. We used to build townhouses that had two 1" drywall layers between units!

Sounds like a plan. I’ll get a material list tomorrow. Thank you!

 

[BlueKnife]

Any reason you can't do the welding first and then frame around it? Are you building a steel box, of sorts?

 

[etpm]

If you really need to weld this safe in place then get some Hardi backer board, wet the studs, put the Hardi backer board in place, wet it, then start welding away. You will have no problems with charred studs.
Eric

 

[square1]

If you really need to weld this safe in place

Good point. I've done removals that I sure wish the original builder would have thought about how future owners were ever going to get that out. Most recent was a player piano that was put in a basement before the house was build (1950s). New owner wanted it out of there.

 

[2manyrocks]

I've read that mig welding can throw sparks 30 -35 feet to also worry about. When I had no choice other than to weld a support column in my parent's house, I wet the wood, and made a deflector shield to try to catch all the sparks. Then I kept checking the basement area afterwards to be sure nothing unexpected was burning.

If this is new construction, I'd clean up all the sawdust everywhere nearby before welding.

 

[Topzide]

Also, have a helper as a "fireman"! Another setup of eyes will help. Welding blankets can also be suspended to help catch stray sparks.

 

[California]

What about welding brackets on the inner side of the panels, that you can line up after the panels are in place. Then weld only the brackets.

 

[BMan2005]

What about welding brackets on the inner side of the panels, that you can line up after the panels are in place. Then weld only the brackets.

All the welding will be done inside the steel room. No exterior side of the welding will be done.

So long story short we got hit by Helene and it’s really just thrown everything sideways. From trying to get our current house live able I haven’t had time to weld the room up before framing started after the hurricane. I also couldn’t get anyone because everyone is so booked out fixing industrial damage. So I will be doing this inside the framed house now.

 

[newbury]

Good point. I've done removals that I sure wish the original builder would have thought about how future owners were ever going to get that out. Most recent was a player piano that was put in a basement before the house was build (1950s). New owner wanted it out of there.

Unless that is a metal piano a good chainsaw should help in disassembly.
I've got a situation with a cast iron piano sitting in my now deceased MIL's garage. It's been sitting there for 40 years. It is untuneable (bent frame), unsaleable and probably weighs over 500lbs. My wife my BIL inherited it a year ago. I'm thinking of trying to use my new plasma cutter to make it into pieces one can carry. Of course there is also a lot of wood structure and I might get a new Stihl 500i to handle the wood

 

[California]

Unless that is a metal piano a good chainsaw should help in disassembly.
I've got a situation with a cast iron piano sitting in my now deceased MIL's garage. It's been sitting there for 40 years. It is untuneable (bent frame), unsaleable and probably weighs over 500lbs. My wife my BIL inherited it a year ago. I'm thinking of trying to use my new plasma cutter to make it into pieces one can carry. Of course there is also a lot of wood structure and I might get a new Stihl 500i to handle the wood

Try offering it free to a high-end piano dealer, anywhere within a day's travel.

A Los Angeles dealer came up 400 miles to get the ancient Steinway upright that Mom had bought when her church moved. We had it on Craigslist for a month @ $600 with no inquiries. The dealer said it was rare, it preceded the common design that started about 1890, so it would sell for a lot after he put a lot of work into it.

The pro piano movers who showed up said this was the heaviest upright they had ever seen.

 

[5030]

Aunt and uncle passed and wife was the executrix and she had to dispose of a Diebold floor safe in the basement. I don't even want to get into that fiasco except to say it weighed well over 2 tons and it wasn't on wheels either.

 

[2manyrocks]

Piano strings and the frame are under a lot of tension.

 

[square1]

Unless that is a metal piano a good chainsaw should help in disassembly.
I've got a situation with a cast iron piano sitting in my now deceased MIL's garage. It's been sitting there for 40 years. It is untuneable (bent frame), unsaleable and probably weighs over 500lbs. My wife my BIL inherited it a year ago. I'm thinking of trying to use my new plasma cutter to make it into pieces one can carry. Of course there is also a lot of wood structure and I might get a new Stihl 500i to handle the wood

The metal skeleton weighed about 350# per the scrapper. The wood cabinet was busted / cut up and might still be providing the homeowner kindling almost year later. Most interesting was some of the specialized fasteners used during the build of that piano.

Aunt and uncle passed and wife was the executrix and she had to dispose of a Diebold floor safe in the basement. I don't even want to get into that fiasco except to say it weighed well over 2 tons and it wasn't on wheels either.

Ugh!

To get the skeleton (tuning board I guess, I'm not a piano man) up the stairs (the piano as one piece never would have fit) several 2x's were screwed into the nose of alternating stair treads, about every 3rd tread, making a ramp, The 4 ton winch on the truck was run through a snatch block connected to the trailer hitch of a vehicle positioned to give a straight pull up the stairs, out the door and into the garage across plywood sheets, and onto a HF 4 wheel flat dolly. The dolly was carefully wheeled out of the garage to the scrappers truck.