OT How fireproof is drywall

Was wondering if I can run a woodstove pipe (singlewall) through a piece of drywall. Want to seal up the fireplace opening. I know thw gypsm is fire proof, but will the paper catch fire from thr radiant heat?

They make a "through the wall" kit and sell them at the home depot, then you can put the sheetrock right up to box they give you, which has triple wall with insulation already in it, much more safe.

Yes, the paper will burn.

You can get fire-rated drywall, but it's primarily because it's thicker.

If you can't leave an airspace, the only truly safe way to run singlewall is through masonry or cement board.

An alternative is to get a short section of triple wall or Metalbesos (or other brand name of same construction) to use as a "thimble" and as far as I know THAT won't meet code if you get an inspection.

Have you folks got access to Fermacell products? Sheets like drywall but harder and completely fireproof. Costs not much more than drywall here and much easier to work with.


Dave

You need a insulated thimble to go through a studwall to a chimney. You can get by with non-insulated one if you use double-wall pipe, but if you use single-wall, you need insulated. They're not cheap (about $200), but cheaper than your house burning down the next time you have a chimney fire. If you use a non-insulated thimble with single-wall pipe, you probably won't have any problems under normal operation, but you have to assume that at some point there will (or could be) a chimney fire.

Selkirk Saf-T Thimble
http://www.selkirkcorp.com/WorkArea/downloadasset.aspx?id=7280

BDM Insul-Flue
http://dalsinmfg.com/insulflue.html

Google those names, and you'll see lots of them for sale from online stores.

Also the wiring, insulation lumber, mouse nests, and anything else in there will burn. You'd better talk to your loacal heat/ac store.

Gordo

You need a class A chimney. That is all

Thanks for all the replys. It is a working fireplace, I'm sticking a woodstove in front of it and just want to cover the fireplace opening, and run the pipe through the cover. Nobody around here sells a through the wall adapter that will work with simple stove pipe. They want to sell you a whole chimmney system that cost a few hundred dollars. I know all about triple wall, class A etc. I will just pick up a piece of sheetmetal tomorrow.

I wouldn't fool with fire.... What if you just bricked up the opening and stucco'd it?



Dave

Like the others said, you definitely need a through wall penetration assembly that is acceptable for this purpose, for the specific wall type or other condition you are penetrating with a chimney pipe.

Simply put, the wall type, whatever it may be ie; typical wood framing, sheathing + any other components making up the wall type, typically interior sheathing of drywall, fiber glass insulation, exterior sheathing ie; plywood, osb + siding, are all combustible, so the through wall assembly must completely isolate the heat from the combustible wall assembly.

Aside from that, sounds like you are blanking off the fireplace, which may be non combustible material and using a stove in front of it, I would most certainly NOT use any kind of gypsum drywall period, same theory will apply as mentioned above, you need to completely isolate the nearest combustible material, from the heat of the stove pipe.

Gypsum drwyall, is a material that can provide a fire rating for a wall, say like a common wall between 2 occupied spaces, or a ceiling below an occupied space, but is absolutely not fireproof by any means, even the thick shaft gypsum drywall boards, used to line mechanical chase's and or shafts, trash chutes etc. in high rise buildings will only provide a specified hourly rating. The purpose of that design in conjunction with other rated components of a building is to achieve a uniform fire rating for an occupied space, so that in the event of a fire, you have that amount of time before the rating is exceeded, to get out and or get to a safe area. Structural steel is fireproofed with spray applied fire proofing, but that does not mean it is fire proof, it is done to provide a specified rating, once enough heat is applied and or the fireproofing material is compromised by excessive heat beyond its design, the steel will heat up and ultimately fail from deflection because its strength is weakened, so it no longer can carry its load.

One excellent reference standard for all kinds of rated assemblies is the UL Fire Resistance Directory, each one listed in their 2 volume book, has been tested.

Way more than your asking for, but maybe of some help. Probably a good idea and get something designed for the purpose, and know it's done right, and your home is safe.

Couple thoughts...
You NEED it to be non-combustible. Not flame retardant or sort-of-won't-burn. Drywall's paper facing will burn. Fire rated drywall is meant to slow the fire spread from one area to another (various assemblies yield different hourly ratings)
Wonderboard/Durock/cement backer baord like you use for underlayment of a tile floor can work and you can always tile it later for a better look
Hardi panels. Made by James Hardi co. (there's other similar mfgs out there). These are fiber cement boards, relatively easy to cut, and paint up nice.
In either option, I would advise light gauge metal stud framing behind it instead of wood studs.
Last, make sure it's installed per code and mfgr. specs. and take pics as you install it. From what I've heard, an improperly installed system is an easy out for the insurance company to not cover anything after a fire.
Good luck.

Thanks But like I said I'm NOT going through a wall, just running the woodstove pipe into the fireplace opening and am going to shut off the fireplace opening. The stove pipe will only be going through the blank I am putting in the opening. I just wanted to get it together tonight. I'll finish it tomorrow.

Sheet metal is your friend in your situation.
Been there done that works good no worry.
Could close it up with sheet rock and put a two foot square piece of sheet metal in for the pipe to go through if $$$ is a problem and no worry about it.
Ken

Heyseed, I know of two homes that have a woodstove piped into a fireplace opening. They both used a sheet of 1/4" steel with a collar welded on for the stovepipe. Both have been in use for 25 years or so. You must seal around whatever you use. If you don't seal it tightly, you can't control the airflow in the event of a chimney fire. You really want to be able to shut off ALL sources of air to the chimney.

Good luck - be safe,
Paul

they sell fire rated gyp board

Single wall stove pipe needs 18 inch clearance from combustables.Sheet metal is the only way and you will need a clean out hole.This is not place for poor work.Make some careful measurments and have a sheet metal shop make it.Fire place chimneys tend to run dirty when a stove is piped into them.