Woodburner fitting

[jonnym]

Hi,

 

I am fitting a wood burner into an old stone fireplace, and I am not sure how to deal with the combustible materials around the edge of the fireplace.

 

I had some insulation fitted via a grant and didn't have a lot of say over how it incorporated the fireplace. You can see from the pictures that the wood studding is directly around the fireplace with insulated plasterboard ontop. 

 

My question is can I cover it with some type of fireproof board and fill any gaps with a fireproof cement, or do I need to cut it back from the fireplace entirely to a safe distance from the stove. Which is about an extra 200mm in my case as the spec for the stove is 500mm either side from combustible materials. Currently the distance from the side of the stove to the side of the fireplace is 300mm. 

 

The fireplace itself is stone and the chimney is lined, so pretty much good to go apart from the combustible surrounding surface.

 

Cheers,

 

Jonny

[ProDave]

Have you bought the stove yet?  Mine only needs 150mm each side to combustibles.

[jonnym]

3 hours ago, ProDave said:

Have you bought the stove yet?  Mine only needs 150mm each side to combustibles.

Afraid so, it is just the little one in the photo. I bought it second hand, so just a cheapy (£120), so a different stove might be an option. Thanks

[carlos21]

That last photo looking up doesnt look great to me, the new wood looks very close, im no expert though.

I have had our linner catch fire before and it generates a lot of heat.

Could you cut back the drylinning around the fireplace ?  

[Alan Ambrose]

Personally I’d stick to the letter and not have any combustibles even if hidden from sight. Use cement board, mineral wool etc.

 

Agree with @ProDave though - modern stoves are much better made in terms of efficiency, air leaks etc.

 

BTW you know that this is notifiable work and should either be under BC control or by a Hetas person? I did mine under local BC. A carbon monoxide monitor one of the requirements. Might want to look at your liner to check that it’s properly airtight.

[Onoff]

All the required clearances are here. Manufacturer's instructions also need to be taken into account in case greater:

 

https://assets.publishing.service.gov.uk/media/6336e58be90e0772dc9651a2/ADJ_2022.pdf

[ProDave]

13 minutes ago, Onoff said:

All the required clearances are here. Manufacturer's instructions also need to be taken into account in case greater:

 

https://assets.publishing.service.gov.uk/media/6336e58be90e0772dc9651a2/ADJ_2022.pdf

Or in my case, less, and building control accepted the manufacturers figures.

[saveasteading]

If there was no bco, the question I'd ask myself is " can this go on fire due to being hot"?

Timber being obviously a combustible material creates confusion.

If it is completely enclosed so that flame can't reach it, and there is no oxygen supply, then it cannot burn.

But the risk is of someone damaging or penetrating the protective boarding.

 

 

The insulated plasterboard is a great concern though. It will fail purely through heat,and then maybe some air can get in. Or eps of pir at a joint might be exposed directly.

 

I think you must remove that area of insulation. The effect on insulation is minimal.

 

BUT it is a BCO  matter so you not only should do it but must do it. And most bcos I've discussed it with think timber burns even when encased, so perhaps change the timber to something else too, just within the zone distance stated. 

Metal stud? Multiple layers of cement board?

If you must regain the insulation then squeeze in some rockwool if you can. 

 

Then you can relax in front of the fire.

 

NB new burners have direct air intake from outside. Yours probably doesn't have that facility so will fail regs.

 

[jonnym]

14 hours ago, carlos21 said:

That last photo looking up doesnt look great to me, the new wood looks very close, im no expert though.

I have had our linner catch fire before and it generates a lot of heat.

Could you cut back the drylinning around the fireplace ?  

 

14 hours ago, carlos21 said:

That last photo looking up doesnt look great to me, the new wood looks very close, im no expert though.

I have had our linner catch fire before and it generates a lot of heat.

Could you cut back the drylinning around the fireplace ?  

Yes it looks like a problem. I have done a quick scan of the  building guidance, and it is too close to the flue. The distance above the appliance seems okay - it is about 650mm, but the distance of that bit of timber to the chimney liner is only about 200mm.

[jonnym]

14 hours ago, carlos21 said:

That last photo looking up doesnt look great to me, the new wood looks very close, im no expert though.

I have had our linner catch fire before and it generates a lot of heat.

Could you cut back the drylinning around the fireplace ?  

There is what I am thinking. Either take the whole wall back to stone, or expose more of the stone work to give the correct/ample clearances. 

[jonnym]

3 hours ago, Alan Ambrose said:

Personally I’d stick to the letter and not have any combustibles even if hidden from sight. Use cement board, mineral wool etc.

 

Agree with @ProDave though - modern stoves are much better made in terms of efficiency, air leaks etc.

 

BTW you know that this is notifiable work and should either be under BC control or by a Hetas person? I did mine under local BC. A carbon monoxide monitor one of the requirements. Might want to look at your liner to check that it’s properly airtight.

Yes, I had heard that, and you promoted me to reach out to them to get a discussion going.

I am a little concerned they will say that the chimney needs doing first. The liner seems okay, but the masonry on the chimney itself needs work and I am hoping I can do that later, rather than as part of commissioning the stove -- purely for cash flue priorities.