Woodburners and dry lining

[4-LOM]

I'm planning to dry line the walls of a room with 2" battens, 2" polystyrene between them and 1/2" plasterboard on top. The plasterboard will then be painted (no plaster or wallpaper). I also want to install a woodburner in the room (obviously I will have to allow for a hole in the wall for the flue to go into the chimney, which will be lined with a flexible flue liner).

What I need to know is: how far should the woodburner be from the walls in order to stop it damaging them. Although I know that plasterboard is fire retardant, I assume you can't have a heat source too close to them permanently. Is the 6" of hearth enough, or do I need more?

[Grunff]

You need *a lot* more. Wood burners radiate a huge amount of heat when they get going. I don't think you want any plasterboard within 2-3 feet of the wood burner.

In reality, this means that you need to surround it with brick/stonework.

[Dave Liquorice]

erm, no mention of any DPM or ventilation. You are just asking for condenstation to form on the, now cold because of the insulation, wall behind polystyrene.

[The Natural Philosopher]

No. just use multibiard instead of plasterboard.

Don't use polystyrene insulation anywhere near tho. That IS dangerous.

>

[jacob]

I'm doing the same except 3" battens with 2" kingspan i.e. 1" gap between plasterboard and insulation. Re condensation - seal gaps in insulation with tape or foam filler and use plasterboard with foil vapour barrier in back. The 1" gap is extra insulation and also sound transmission reducing. The woodburner will be about 6 to 9" from the wall and I intend to put that asbestos substitute board whose name I've forgotten, behind the stove and flue pipe. Or, if I can afford it - steel plates with black stove finish - to absorb heat and radiate it back into the room. This will even out heat transmission to the wall itself and reduce hot spots. I've already fitted the stove, a 'Firebug' from

and we are very pleased with it. It also burns sawdust by virtue of it's pyramid shape - i.e. the sawdust heap in the stove settles slightly making an air gap all round and combustion then takes place over the surface. i.e. 2 or 3 shovelfulls at a time.

cheers

Jacob

[The Natural Philosopher]

Polystyrene is a vapour barrier by and large. You can drink coffe out of it without it dripping through.

Its only rockwool/fiberglass that really needs a vapour barrier.

Just make sure its not polystyrene behind it.

[4-LOM]

I know. My original post was specifically asking about how close you can safely put a woodburner to plasterboard so I didn't mention every detail of the dry lining.

However, this leads on to another point that I'm not sure about: I've read that the DPM can be attached with "staples". What kind of staples?

[4-LOM]

Can I assume that any other commonly used insulation material IS safe? And if I use multiboard, will this be sufficient to protect the wooden battens behind it?

I do have the option of leaving the brick walls bare in this corner, but they don't look very nice and I'd prefer to have them insulated somehow.

[The Natural Philosopher]

More or less. All the others char and fume but don't really burn.

Not sure about IMM's famous celullose stuff tho. That probably burns better than a baby soaked in Napalm.

Its all a matter of how hot/how near. You can heat pslaterbaord up to red heat. The cvardboard burns, teh gypsum goes crimbly and falls to pieces. It is quite a good insulator.

Mutltiboard you can do the same to. It holds together better if you do.

Neither of them will protect woodwork directly behind if you play a blowlamp over the top for long enough.

OTOH if its just a couple of hundred C, i'd say yes.

ell, get teh stove in, light it, and nail a small piece of batten to the hottest part of teh wall, and see if it chars. Then nail a bit of plasterboard ovet the top and see what that does. If its obvious that ist getting too hot, use multiboard. If necessary use sapcer strips betwen the main board and the batten to increase insulation.

[Steve Taylor]

Loaded with Boron, like suspended ceiling tiles - I can weld on them.

Steve

[The Natural Philosopher]

What? Babies soaked in Napalm? Or were you referring to IMM's and simply misspelt Boron?

[4-LOM]

If it definitely IS too hot and I have to use multiboard, how should I fix it? If I use metal screws or nails, won't these conduct the heat right into the battens?

Also, what to do about joints? Where it meets the normal plasterboard will necessarily be at a safe distance but there will almost certainly be a corner join between 2 multiboards which is not at a safe distance, so presumably joint tape is out. And if I don't seal it somehow that could be an easy way for heat to get through and melt the DPM. Aaarrghh! it's all so complicated...

Or am I just being paranoid?

[The Natural Philosopher]

I think you are being too fussy.

The point of using masterboard etc. is to add a little more fire barrier and insulation. If the wall is getting that hot, then nothing short of cast iron will be good enough anyway.

All you are really concerned about is not having e.g. bare painted wood near the fire. That will bubble smoke and char. Stivking sud behind plasterboar will take a fair bit of heat, up to the point where the board starts to crumble. The wood should be fine up to thatpoint.

Masterboard etc is not so much something that does any better than plasterboard in normal terms, but simething that, in the event of a serious fire, or total overheatuing of your fire, will protect the wood longer, becaus it maintains physical inegrity at higher temps aywy.

But by the time you get that hot, any painted plasterwork is going to be seriously blackened.

To summarise. If it gets that hot round teh stove, a paint fih is not going to survive, in all probability: Use a metal plate screwed down or smething.

If it doesn't get that hot, plasterboard will outlast the paint its covered with, but mulitibard will outlast that in a fire.