Wood burners

[Peter009]

Just wondering if I can check this as am looking up the regulations and cannot find specific details.  I am installating a Hamlet multi fuel stove with back boiler  4.9 kw I am proposing to use 20 mm granite on a 30 mm non combustible base as the hearth and would like to use a steel sheet for the wall mainly for decorative reasons but also I understand that steel is heat resistant am I correct that is right or is there something in the regulations that says that I cant use steel.  The steel is 1.2 mm 18x SWG and would be powder coated.  I will keep the stove at least 10 inches from the wall as well.  The flue is double skinned thanks in advance am hoping I am right and somebody can confirm that I am going the right way with this the last thing I want to do is get this wrong !!

 

[LadyG]

Read this recent thread:

 

[Alan de Enfield]

2 hours ago, Peter009 said:

I understand that steel is heat resistant

The steel is heat resistant in that it will not melt - however it will conduct all of the heat 'straight thru'.

The idea is to have a material that is non-heat conducting so as to avoid scorching (and potential fire) of the walls behind it.

 

I built a surround with a framework giving a 1" air gap, this was covered in the 12mm thick fireproof calcium silicate sheeting, which was finished with porcelain tiles.

The other side of the wall still became quite hot (more than just warm) 'to the touch'.

 

I would not suggest using steel.

 

The industry recommendations are :

 

Heat PROTECTION PANELS

Stoves and uninsulated flue pipes can easily get hot enough to set fire to paint, wood or other combustibles a distance away. A single fireproof panel fastened straight to a wall is no use – heat can pass straight through it. One way of making a good protection panel is to have: a 10mm air gap (supported on offcuts), then 25mm thick calcium silicate board (which can be tiled) then at least a 45mm gap to the stove body, all extending at least 200mm above the stove. (7) (This construction can be used as the hearth underneath a stove with legs, if topped by a 15mm cement-board panel.)
 

This was a 3Kw stove I installed :

[Peter009]

1 hour ago, Alan de Enfield said:

The steel is heat resistant in that it will not melt - however it will conduct all of the heat 'straight thru'.

The idea is to have a material that is non-heat conducting so as to avoid scorching (and potential fire) of the walls behind it.

 

I built a surround with a framework giving a 1" air gap, this was covered in the 12mm thick fireproof calcium silicate sheeting, which was finished with porcelain tiles.

The other side of the wall still became quite hot (more than just warm) 'to the touch'.

 

I would not suggest using steel.

 

The industry recommendations are :

 

Heat PROTECTION PANELS

Stoves and uninsulated flue pipes can easily get hot enough to set fire to paint, wood or other combustibles a distance away. A single fireproof panel fastened straight to a wall is no use – heat can pass straight through it. One way of making a good protection panel is to have: a 10mm air gap (supported on offcuts), then 25mm thick calcium silicate board (which can be tiled) then at least a 45mm gap to the stove body, all extending at least 200mm above the stove. (7) (This construction can be used as the hearth underneath a stove with legs, if topped by a 15mm cement-board panel.)
 

This was a 3Kw stove I installed :

Hi thanks for that I was going to use calcium silate boards under the steel sorry did not make that clear as I dont want tiles for the look of our boat so wondering if using calcium silate boards under the steel would be OK or in your opinion definitely a no to steel over it.  thanks

Just now, Peter009 said:

Hi thanks for that I was going to use calcium silate boards under the steel sorry did not make that clear as I dont want tiles for the look of our boat so wondering if using calcium silate boards under the steel would be OK or in your opinion definitely a no to steel over it.  thanks

By the way lovely stove and fireplace 

[Peter009]

Also can these boards be cut and joined have seen some on ebay but a bit small so wondered if I could join them or should they not be cut sorry an area where I really lack knowledge thanks for your answers

[Alan de Enfield]

2 minutes ago, Peter009 said:

Hi thanks for that I was going to use calcium silate boards under the steel sorry did not make that clear as I dont want tiles for the look of our boat so wondering if using calcium silate boards under the steel would be OK or in your opinion definitely a no to steel over it.  thanks

By the way lovely stove and fireplace 

I'm no expert but would suggest that the steel will be decorative only and do nothing to reduce the heat transfer. Folk have used copper-sheet so I suppose it can be done.

 

Suggest using thick (25mm) calcium silicate sheet and leaving a vented air gap (not sealed at the top) so the excessive heat can dissipate.

If you follow the industry guidance at least your insurers cannot say the installation was faulty - should the worse happen.

[rjasmith]

As you are "looking up the regulations" (ref your OP) why not have a go at using Manchester City Library's excellent website to read the definitive advice on boat stove installation from British Standards Code of Practice, BS 8511:2010. The "Soliftec" guide drawing everyone quotes is merely a precis of BS 8511 and is very helpful but doesn't give all the options by any means. The Boat Safety Scheme also extensively refers to BS 8511 as I'm sure you already know.

 

I have endlessly explained on CWDF before how to access this doc using the library site and here's a link to an earlier post that does this as it's not completely obvious! The MCL site allows any UK resident to view BS docs for free and you do not have to be a library member.

 

Using a metal shield is completely acceptable to BS 8511 and is Option B (para 7.3). Option A is the usual insulated board and Calcium Silicate is clearly the best.

 

For Option B the type of metal is not specified so steel would be fine. The way the metal shield is fixed is vital and there must be an air gap at the bottom as well as the top to let convection air currents pass up behind the shield. Also the metal sheet must be fixed to the combustible wall behind using insulated stand offs. BS 8511 gives excellent sketches of how this can be done and specifies a whole range of acceptable gap dimensions etc. 

 

Richard 

 

[Lizette]

Hi All

 

I have used calcium silicate board , it was tiled with flexible grouting . It also has an air gap. It is sitting on stone with the recommended calcium silicate underneath. I have refurbished the Valor willow and replaced many parts , replaced flue , chimney and rope.

 

I have lit the fire for the first time and the tiles in certain area is getting too hot! I am , to say the least quite peeved.

 

I have got it at an angle ,with approx 3 inch gap to wall ..

 

Is there some kind of guard I could use between the  tile and fire or will I have to move the fire further away. 

 

I just do not understand it.

 

Any advice?

 

Lizette

 

[Tracy D'arth]

5 minutes ago, Lizette said:

 

 

I just do not understand it.

 

Any advice?

 

 

 

I do, you have insulated the tiles from losing any heat into the substrate, quite rightly.

 

They will get hot. Question is, how hot is too hot? Are they cracking? I would be very surprised if they could not stand the radiated heat, they are a fired clay component at much higher temperature than your burner.

 

 

[mrsmelly]

9 minutes ago, Lizette said:

Hi All

 

I have used calcium silicate board , it was tiled with flexible grouting . It also has an air gap. It is sitting on stone with the recommended calcium silicate underneath. I have refurbished the Valor willow and replaced many parts , replaced flue , chimney and rope.

 

I have lit the fire for the first time and the tiles in certain area is getting too hot! I am , to say the least quite peeved.

 

I have got it at an angle ,with approx 3 inch gap to wall ..

 

Is there some kind of guard I could use between the  tile and fire or will I have to move the fire further away. 

 

I just do not understand it.

 

Any advice?

 

Lizette

 

It doesnt matter if the tiles are getting hot if mounted on fireproof board with a gap between that and any combustibles. How far away is the stove from the tiles anyway?

[Lizette]

Hi Both

 

I would say 3 inches but maybe a little less at corner. The tiles are very difficult to touch in one particular area. It is not just warmth, it is hot . I am planning throughout the winter leaving it ticking over through the night but I don't feel happy with the tiles being too hot.

[Mac of Cygnet]

No-one seems to have mentioned this, but the colour of the surround is important, especially if using metal.   Most of the heat reaching the surround is radiant, which is absorbed much more by dark colours, especially black.  I have a polished beaten copper surround which very rarely gets more than warm, which is good because I have no idea what is behind it.  If I let it get a bit dirty (surely not!) the temperature difference is very noticeable.

[mrsmelly]

2 minutes ago, Lizette said:

Hi Both

 

I would say 3 inches but maybe a little less at corner. The tiles are very difficult to touch in one particular area. It is not just warmth, it is hot . I am planning throughout the winter leaving it ticking over through the night but I don't feel happy with the tiles being too hot.

Like many of boats for some reason that is fitted very close to the tiles but it wont set on fire if mounted as described. mine is fitted in top left corner and is 8 inches away from the hull and 18 inches away from the front bulkhead. Why they are often stuffed tight into the corner always amazes me. Can you not move it 3 inches out and re jig the flue?

[Lizette]

Hi 

 

My tiles are a medium grey. Not sure what to make of that?

[Ally]

What tiles have you used? The worst really is that a glaze on then would craze. They aren't going to catch fire. As long as you have used the fireboa4d and have a good airgap, ideally with venting so any hot air can escape, then it shouldn't be a problem.  3 inch is a bit tight though really, not ideal, but within recommendations.  Minimum recommendations to protected surfaces are 45mm, then 25mm fireboard then minimum 10mm gap.

[Chewbacka]

My tiles can be above boiling as a tested with a damp finger, so hot.  I did use a high temp adhesive to bond the tiles, and so far not fallen off.

Edited November 29, 2020 by Chewbacka

[Mac of Cygnet]

3 minutes ago, Lizette said:

Hi 

 

My tiles are a medium grey. Not sure what to make of that?

 

Fine.  The colour thing is most important with metals, which will conduct heat very rapidly to the other side, affecting whatever is there.    Tiles are not only thicker but less conductive.  I bet black tiles will get very hot to the touch, though.

[Lizette]

2 minutes ago, mrsmelly said:

Like many of boats for some reason that is fitted very close to the tiles but it wont set on fire if mounted as described. mine is fitted in top left corner and is 8 inches away from the hull and 18 inches away from the front bulkhead. Why they are often stuffed tight into the corner always amazes me. Can you not move it 3 inches out and re jig the flue?

I guess if I turned it , so it wasn't tucked in to corner at an angle and had it facing straight down the boat , it would leave me with a gap of about 6 or 7 inches. Although I would not be able to see the glow of the flame if sitting beside it , at least I would feel happier and safer.

I must admit , I personally hate things on an angle but I was working with what was here as much as possible.

Just when I thought I had completed the job!! I shall move it tomorrow , unless anyone has anything else to add.

 

Thanks all and I hope you are all staying positive during this weird time

 

[Tracy D'arth]

I reckon you are OK but if you want peace of mind, an infra red thermometer is handy to have and they are less than a tenner on eBay. Good for Covid temperature checks too.

#

I would not bother moving it, it will make very little difference IMHO.

Edited November 29, 2020 by Tracy D'arth

[Lizette]

8 minutes ago, Ally said:

What tiles have you used? The worst really is that a glaze on then would craze. They aren't going to catch fire. As long as you have used the fireboa4d and have a good airgap, ideally with venting so any hot air can escape, then it shouldn't be a problem.  3 inch is a bit tight though really, not ideal, but within recommendations.  Minimum recommendations to protected surfaces are 45mm, then 25mm fireboard then minimum 10mm gap.

Yes, I agree, it is tight . I think I will move it ,  Thanks

3 minutes ago, Tracy D'arth said:

I reckon you are OK but if you want peace of mind, an infra red thermometer is handy to have and they are less than a tenner on eBay. Good for Covid temperature checks too.

#

I would not bother moving it, it will make very little difference IMHO.

Yes, good idea - Oh no , now I don't know what to do.

 

[Tracy D'arth]

Mine is the same, quarter turned in a corner, tiles are on black steel sheet, with insulation and a small air gap behind. I can stoke the bejaysus out of it and have done so for years, its absolutely fine,

You are well insulated from the wood behind, the tiles will stand it just fine, in manufacture they are fired at 1150 C  !!!!

[noone]

10 minutes ago, Lizette said:

Yes, I agree, it is tight . I think I will move it ,  Thanks

Yes, good idea - Oh no , now I don't know what to do.

 

Pretend to move it,but don't tell any one!.?...If any one asks..."it was like that when you got there!".??

[Lizette]

ok, thanks. I do think I have been reading all the horror stories about fires on boats and I have got myself a little freaked out

 

1 minute ago, Leggers do it lying down said:

Pretend to move it,but don't tell any one!.?...If any one asks..."it was like that when you got there!".??

Lol?

[mrsmelly]

4 minutes ago, Lizette said:

ok, thanks. I do think I have been reading all the horror stories about fires on boats and I have got myself a little freaked out

 

Lol?

To be honest if the tiles are fitted onto fire proof board with an air gap between that and the hull sides etc you will have no problem. Still think its too near the sides and always wonder why peeps fit em like it? theres plenty of space for small stuff like a squirrel to be further out and heat will circulate better rather than heating the tiles up.

[noone]

5 minutes ago, mrsmelly said:

To be honest if the tiles are fitted onto fire proof board with an air gap between that and the hull sides etc you will have no problem. Still think its too near the sides and always wonder why peeps fit em like it? theres plenty of space for small stuff like a squirrel to be further out and heat will circulate better rather than heating the tiles up.

Job done!....I always wonder why people fit small burners that you constantly have to feed...I have a villager "kitchener" fitted across the boat.