Multi fuel stove and wooden fire surround regs

[Doug71]

Any experts out there on fitting multi fuel stoves etc?

I have to make a wooden fire surround for a multi fuel stove. It's a typical set up where the stove is set in the chimney breast where I presume there used to be an open fire.

Am I correct in thinking nothing combustible can be within 450mm of the stove? The customer was hoping the surround would come closer than this to the stove, the surround will be painted so could I make part of the surround out of some kind of cement board like hardiebacker? Is it okay to clad pieces of wood that are closer then 450mm with cement board? Can it be 6mm or does it need to be 12mm?

It all seems a bit daft as I know they will have perfect looking logs (which will never be burned) stacked around the stove for decoration once it's all finished and up and running

Thanks, Doug

 

[Cabinetman]

Hi Doug, The regulations are probably best looked up online, it’s complicated!
There is a way of shielding with steel and a gap, which seems daft to me as it will transmit the heat as well as if it wasn’t there!

 

[Sandyn]

A good place to start is the HETAS Site. you should be able to find most things in there and links to some building regulations. It takes ages to dig through all the info.

 

[Fergie 307]

I had a similar problem, an oiled oak bean across the front of the opening. I was concerned that heat from the stove would at the very least dry out the beam. I fitted a piece of 2mm thick stainless steel in an L shape. The longer section inside the chimney and the shorter section just under the bottom edge of the beam, leaving a gap of about 5mm between the two. It's not noticeable but protects the beam from the heat.

 

[Fergie 307]

Hi Doug, The regulations are probably best looked up online, it’s complicated!
There is a way of shielding with steel and a gap, which seems daft to me as it will transmit the heat as well as if it wasn’t there!

No it wont, think of the safari roof on a Land Rover, same principle. You have a second roof panel stood off the "real" roof. This reflects the heat so the real roof stays much cooler, the gap allows heat to dissipate so that although the safari roof will get hot enough to fry your breakfast on it, the roof under it remains relatively cool.

 

[Phil Pascoe]

I had a similar problem, an oiled oak bean across the front of the opening. I was concerned that heat from the stove would at the very least dry out the beam. I fitted a piece of 2mm thick stainless steel in an L shape. The longer section inside the chimney and the shorter section just under the bottom edge of the beam, leaving a gap of about 5mm between the two. It's not noticeable but protects the beam from the heat.

I think the problem is the regulations more so than the practicalities.

 

[Sandyn]

here is Approved Document J for England. See section 2.22

 

[gregmcateer]

Maybe talk to whoever is installing the stove - in my experience they're good blokes and happy to share knowledge

 

[Krome10]

Do you know which stove they are getting?

RE cladding the combustibles, I think there's something in the regs which stipulates an air gap between the non-combustible "shield" and the combustible it's shielding.

 

[Ollie78]

When I did my fireplace I replaced the plasterboard above with 12mm cement board and put a massive bit of slate in the hearth.

A quick tip the stove guys told me, which I did use was if you are going to plaster or cement render anywhere near the fire, use monocouche render. Like k-rend etc.
It won't crack in the heat like cement or plaster, working great 5 years now.
Was going to do a mantle above but because of the regs it would have needed to be strangely high and would look odd.

Ollie

 

[Bod]

It all seems a bit daft as I know they will have perfect looking logs (which will never be burned) stacked around the stove for decoration once it's all finished and up and running

Thanks, Doug

This is a dangerous practice. Logs stored like this WILL get too hot, and burn! (even if they are soaking wet, covered in snow)
At least 6 inches/150mm gap should be left whenever the fire is in use.

Bod

 

[Fergie 307]

Agree, that is a very dangerous thing to do. Other thing you need to consider is ventilation, you need to make sure there is an adequate supply of air to feed the stove, otherwise it will suck all the oxygen out of the room, also not a good idea!

 

[Sandyn]

That's covered in part J1 of the Approved Document J

 

[Woody2Shoes]

It's a while since I last looked at this, but you've got three sets of 'rules' to work to:
The manufacturers installation instructions, HETAS, and Building Regs as mentioned above.
I remember being a bit shocked by how relaxed the rules were about a combustible mantlepiece above, I'm not sure about sides/back/underneath.
As already suggested, you do need air gaps all round really, otherwise - apart from the fire safety and ventilation aspects - there won't be proper covection currents to move the heat out of the stove into the room. A 'boxed-in' stove has to rely pretty much solely on radiation to heat the room.

 

[Sandyn]

You need to confirm what type of stove has been installed, but from what I remember my stove was classed as an appliance which cannot cause the hearth temperature to exceed 100C. What I can't remember is if this is a requirement of a HETAS approved stove?? Section 2.29 diagram 27 a shows the construction of the hearth for such a stove
Needs to be 12mm thick, non combustible material . Dimensions come from diagrams 24 and 26.

What caused me a bit of concern was the hearth size in front of the fire. My one has a door, so it needs to be 300mm from the firebed opening, but the door is huge, so when swung open fully, it extends beyond the hearth and often has burning embers sitting on a ledge on the door. I extended the hearth an extra 130mm for safety.

 

[D_W]

I can tell you something that works - I have a large forge (like the ones you see on forged in fire). It's stainless steel on the outside, which I thought would be a good idea so that it doesn't oxidize. Come to find out, it's double lined with refractory blanket and firebrick in the bottom. The inside of it can be bright orange for an hour and you can touch the steel on the outside.

My point being the refractory blanket will probably not transmit heat fast enough for the opposite side of a divider to get hot (the heat will dissipate from it faster than it can heat) if you make a clad setup with an inch or so of it sandwiched between.

But it will also prevent the heat from traveling laterally and heating the hearth, which is sort of a bummer if you're used to a hearth radiating slow even heat.

That said, I wouldn't do anything that doesn't meet code not for legal trouble, but for issues with insurance adjusters if you should ever have an issue.