We’ve just had our fireplace opened up for a stove, but the guy who was going to fit it isn’t available for a bit. Looking at doing it myself, so getting stuck into the building regs.

I’m pretty sure there’s only one brick thickness to the next room at the back of the hearth. Got a 5kw stove to put in, probably with 50mm airgap at the back. We’ve taken out a 2″ thick fireback which has had open fires in it for 80 years without incident.

So I’m guessing the wall thickness we’ve got and the planned install isn’t dangerous, but is it important? Or anything building control would actually check?

thanks for any pointers.

Bumpster!

Any thoughts?

Have you checked Document J?

Page 38-40 of Part J.

Sorry, missed some words that would have made it more obvious where my starting point was:

so getting stuck into the building regs part J which state on page 40 that min. thickness of a back wall in a fireplace recess of 200mm

I’m pretty sure there’s only one brick thickness to the next room at the back of the hearth. Got a 5kw stove to put in, probably with 50mm airgap at the back. We’ve taken out a 2″ thick fireback which has had open fires in it for 80 years without incident.

So I’m guessing the wall thickness we’ve got and the planned install probably isn’t dangerous, but is it important? Or anything building control would actually check?

Or do I need to get the builder back to strip the fireproof board off and put another row of bricks in?

Check what the stove’s manual says. That trump’s part J.

For example, if your stove is a convection one, or has a heat shield on the back, it likely allows far smaller clearances to combustibles at the back. If it’s a straight radiation stove then you’d need the extra row of bricks

Different stoves are better insulated. The manual will say how much gap you need at the back. If the bricks are within that, you need additional insulation. Most are 100-200mm but check the fireboard performance, as this may reduce the temperature sufficiently.

Thought about doing it myself. Looked at what was involved. Decided to get someone in.

Booked them in July, fitting is next week!!

Not much help with building regs etc but just not something I was willing to take on…

We looked at it a few years ago and felt the fitters were taking the piss. Did it ourselves. Might remove it when we move. 5 years ago and no deaths/fires to report here.

My experience is the same as neilnevill its all about the specs in the stove brochure, every Stove has its own min distances. I did find one that was in the 40mm all round region, but most are a fair bit more. I ended up having to put in an offset Stove pipe to get the gap at the back, for the stove I wanted.

Are you sure stove instructions override building regulations?
I was always under the impression that you worked with whatever was the most stringent. Which is unlike working with gas or oil appliances.
And clearances to combustibles can’t be got round with heat proof board.

Stove instructions definitely override the regs.

B.nana. You’ve misread. You can go closer to a non combustible, but that then needs to be 200mm thick.

neilnevill, the only documents that can be accepted in lieu of compliance with an approved document is compliance with a BS,ISO or DIN standard, Agrement Board Certificate.

Where does your information come from? 🙂

Sorry, missed some words that would have made it more obvious where my starting point was:

so getting stuck into the building regs part J which state on page 40 that min. thickness of a back wall in a fireplace recess of 200mm

Diagram 28? That refers to Fireplaces for open fires (referenced from para 2.30 p38)

I suspect that para 2.32 (p40) and diagram 30 to which it refers (p42) are relevant, noting that the wording in para 2.32 allows thinner material with equivalent fire protection.

Note that para 2.33 says that “…clearances shown in diagram 30 may be reduced to manufacturer’s recommendations…”

It’s a while since I fitted mine, but I recall it being pretty clear if you work through the AD systematically (I’m not about to do it again 😉 )

It will be fine to install like it is

Thanks all for the assistance, building regs are contradictory and the BC lady round these parts doesn’t visit beforehand to tell you what they’ll be looking for to sign off, just after you’ve finished to tell you it’s fine or to tell you you need to redo some things.

josh, I’m confident it will be fine, I just don’t want to install it like this, then have the lady tell me I need to pull it out, brick out, reline, buy elbow joints and get her back in again.

Given that there’s a guy who’ll come and do it for me and sign it off for not much more than I can do it for plus £266 BC visit, I’m tempted to do that.

edit: tillydog – I’m sure there’s more clarity if I go looking for it. Reading though them and the advice on stovefittersmanual, it seems there’s a lot down to interpretation and the bottom line is that you just need to make sure whoever’s signing it off is happy with it, and checking in advance doesn’t seem to be an option.

Also, the manufacturers data card in the manual says clearance to combustibles in front of the stove needs to be 900mm. so unless you’ve got a stone or tile floor, you need close to a metre of hearth?!

Also, the manufacturers data card in the manual says clearance to combustibles in front of the stove needs to be 900mm. so unless you’ve got a stone or tile floor, you need close to a metre of hearth?!

BR says 30cm so I’d go with that.

So you can just go around all the regs and guidelines and pick the smallest numbers? 😀

yep 😉

[clearance to combustibles in front of the stove distance is ,AFAIA, in case something falls out of the stove when the door is opened… 900mm seems pretty excessive!]

ive done all my stoves myself bar one, i’ll come to that.

the stove manual outweight everything.

dont worry about building regs unless you are planning to sell the house. but do refer to them for installation, as said though, the stove’s instructions outweigh them.

you do not necesarily need a flue liner although every installer will tell you you do. good way of adding more 000 to the invoice.

DO get your flue checked by someone you can trust. it helps that my in law is a sweep, but the danger from co2 in an old leaky flue cannot be stressed enough.

that one installation i didnt do… for my holiday let i obviously needed everything checked off and although i easily could have put in the stove and flue i decided it best (sic) to use an established company.

i am not a hetas qualified installer, but even i could see that when they had finshed and signed it off as safe there were some massive breaches of regs and downright common sense. i’m talking scraps of wood used as chocks in the attic space to wedge the flue pipe amongst other things. threats of legals sorted it but i tell the tale to prove that even when using a ‘professional’ be careful and definitely make sure you have co2 alarms.

The whole HETAS thing is an absolute rip off.

So many horror stories.

It’s a 3 or 5 day course FFS.

the whole building control thing is a rip off too. £266 for a 20 minute visit?

The decorative hearth rules are for ’ember protection’, normally 300mm but more if stove is raised on tall legs. The constructional hearth (if needed) is about heat going to the floor, seems excessive to me but it’s usually 450mm iirc. Clearance to combustibles in front of stove is stuff off the floor, furniture, I thought it was a metre but perhaps that’s from my stove manual. Clearance to side ways combustibles is usually 300mm.

Hetas is a self certification scheme, they shouldn’t (but probably do) certificate your work.

Are you worried about CO2 or CO?
Pretty sure catalysts on cars convert CO to CO2?

Given that there’s a guy who’ll come and do it for me and sign it off for not much more than I can do it for plus £266 BC visit, I’m tempted to do that.

After weighing it all up, that’s what I did. The HETAS guy who came and fitted it (£300 incl materials), who also happened to be a fireman in his day job, seemed far less fussy about min dist to combustibles than I was. In order to fit the stove instructions, I had planned on an offset stove pipe and was still a tad short sides and back, but he seemed happy and was fitting a straight pipe, until I insisted otherwise. He also didn’t question what materials the builders had used in the fireplace, it just generally seemed to be what he considered was not dangerous rather than rigidly adhering to regs and instructions, which suited me, I’ve got the signed HETAS certificate anyways.

I know a fireman who has his HETAS and fits stoves on his days off, a total numpty, hasn’t a clue.
Probably a crap fireman as well.
I love these threads, you learn so much. 😕

As a competent DIY .. I was going to have a go at fitting a stove.

But after I looked at all of the above like you guys have and wondering “what if” I’ve decided to get a Bio-mass “stove”.

It’ll probably not give out much heat (I dont really need it for that) but at least we’ll not be stinking the neighbourhood out and we’ll be able to light it easily, as well as not have to clean it.

I’ll let you know if its any good.

This guy didn’t fill me with confidence, that’s for sure. despite it suiting me (the slight infringements on min dist to combustibles), I was left from the whole experience, thinking that HETAS cert / DocJ / appliance install instructions etc was all a bit of a farce if HETAS certified installers were just ignoring convenient bits to do the install. Hey Ho.

I love these threads, you learn so much.

twinw4ll, I was hoping you’d chime in. There’s plenty of scope for interpretation e.g. distance to combustibles from flues can be halved by heat shields, but there’s nothing to say that distances from stoves can be reduced)

My current thinking is that “signoff” via HETAS or BC is only worth as much as the person doing it, somewhere between nothing and something. You may as well make yourself aware of the various aspects of the regs, which bits are very important and where the areas of interpretation are, make your choices based on not wanting to destroy your home or and/or kill your family and neighbours, do it yourself and find someone suitable to give you a bit of paper for it.

Obviously the safety of that approach depends entirely on the person doing it, as much as the signoff depends on the person doing the signoff, but I think I’m on the right end of the safety bell curve. And no-one who’s reading this will know whether I am or not, going back to the point “I love these threads, you learn so much”

make your choices based on not wanting to destroy your home

For most instances Isn’t that just not ever leaving the door open whilst unattended, getting the flue / chimney swept regularly and maybe not massively overloading it?, none of which are controlled by regs. It’s a sealed box at the end of the day. Mine was short by 5% on distance to combustibles which I was ok with, but unsure it would get signed off, turned out I didn’t have to worry.

and/or kill your family and neighbours

see above, CO2 detectors (that’s obv a basic requirement) and take professional advice on flue or not, or just get a flue installed no matter. My chimney is within houses, so for me as a decent person, it was a no brainer, I absolutely did not want to cause any impact or issue to my neighbour, a few hundred quid on a flue was worth that peace of mind.

Nowhere have I seen that you can halve distances to combustible materials with a heat shield. Can you link to where it says that in the approved document.

Ignore me think I’ve just found it! Been a while since I did anything solid fuel related!