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The Boat Safety Scheme has a page on solid fuel stoves https://www.boatsafetyscheme.org/stay-safe-advice/solid-fuel-stoves/new-stove-new-chimney/ which lists the British Standards CoP for stoves and lists a source of information from soliftec. Note that a single wall flue has to be kept further away from combustible surfaces than an insulated flue according to the soliftec information.

Are you saying that the single skinned flues on the majority of boats don’t meet current BSS regulations then? You have got to be careful with what is a requirement and what is a recommendation. The link to the Soliftec stove install diagram. http://www.soliftec.com/Boat Stoves 1-page.pdf

The purpose for the air gap is to keep the hot fireboard off the wood. At only 12mm thick and 100mm behind the stove that will reduce to about 80mm with the board and tiles, the rear of the board could be very hot. You could bond a thermocouple to the back of the board when fitting and measure the temp when it's all done for peace of mind. I think you do have enough space for a 25mm board 8mm for tiles, 50mm gap between to the stove and a 10mm air gap as total is 93mm and you have 100mm and will conform to the soliftec recommendation.

I'm going to take the wall board/tiles all the way up on the saloon stove flue but I've used copper sheet behind the Premier flue in the back cabin. Behind the copper is 50mm rock wool on top of the 25mm PU sprayfoam (fire retardant) and then the cabin side steel. The copper is fixed to the battens on top of strips of fireboard. With the Premier going full tilt the copper only gets slightly warm to the touch near the stove. I've "mocked up" the saloon stove installation and did some flue temperature tests a while ago on the flue with the Hamlet Hardy 4 going full tilt. I got about 250°C at the stove top and about 80°C near the roof. This is with a single skin conventional steel pipe flue of 100mm id. The roof collar remains at only about 25 - 30°C due to the enormous heat sink effect of the steel roof. Of course the Soliftec tests on whether a double skin flue pipe helps to reduce fuel consumption are another debate entirely and it would be great if there were some other comparative tests done on that subject another day! Richard

I am also clear that the BSS requirements have never gone into any detail of clearances, type of heatproof board, hearth material etc for solid fuel stoves. Most Mfrs Stove installation instructions will be written around the Building Regs (Doc J) for houses so they often won't work in a boat! Thats why I think it's a good plan to try to have a look at the BS 8511 Code of Practice itself where, provided your stove is built and tested to BS EN 13240 (most are these days - look for a plate on it somewhere), you can use all the "boat friendly" guidance in there. BS 8511 is not a BSS doc and nor is it mandatory and it is also not related to the RCD. (Actually there are no solid fuel stove specific requirements in the RCD ISOs either, just a generalised fire protection document ISO 9094!). I've recently discovered a really easy way for anyone to look at BS 8511 or indeed most other BS or ISO stds. Just join Manchester City Library (anyone resident in UK can join for free), then use their website's link to the BS website (BSOL). Put "8511" into the Search box on the page that comes up and then click on the "Quick View" button to bring up a read only copy of the dreaded CoP. Actually I think you may not even need to join MCL - see if this link works. The well known Soliftec sketch that others have linked to is a splendid precis of 8511 but the full doc gives a much greater variety of options for clearances depending on type of wall board and stove positioning. I've just counted eleven different clearance options! The Soliftec sketch gives a fixed set of "rules" on a rather strange looking picture of a boat and is just one page. 8511 gives a whole lot more in 44 pages and I think their drawings look better! Richard

I didn't realise this thread had got duplicated and put a few words on the other one! Here's what I said:- This is an old chestnut as far as I'm concerned!! The Soliftec drawing is at least available to view by anyone for free which is good but it only gives a reduced set of the recommendations. In particular the recommendations for spacings in the drawing may be pessimistic depending on the actual stove arrangement you have and also the type of fireboard your installers have chosen. The definitive set of recommendations for boats are given in a British Std Code of Practice BS 8511 (the Soliftec drg refers to it as does the Boat Safety Scheme). Unfortunately this document is not available to view for free and costs around £150 to buy. Hopefully your installer has a copy and knows what it says - ask them!! There are drawings in it that are much more detailed than in the Soliftec drg and take account of various possible stove arrangements and fireboard types which will result in a whole host of different spacing figures from combustible material! If your installer is not aware of this document I'm afraid my opinion is that you shouldn't be using them! Richard

This is an old chestnut as far as I'm concerned!! The Soliftec drawing is at least available to view by anyone for free which is good but it only gives a reduced set of the recommendations. In particular the recommendations for spacings in the drawing may be pessimistic depending on the actual stove arrangement you have and also the type of fireboard your installers have chosen. The definitive set of recommendations for boats are given in a British Std Code of Practice BS 8511 (the Soliftec drg refers to it as does the Boat Safety Scheme). Unfortunately this document is not available to view for free and costs around £150 to buy. Hopefully your installer has a copy and knows what it says - ask them!! There are drawings in it that are much more detailed than in the Soliftec drg and take account of various possible stove arrangements and fireboard types which will result in a whole host of different spacing figures from combustible material! If your installer is not aware of this document I'm afraid my opinion is that you shouldn't be using them! Richard

Hello As we speak, my new stove is being installed by professionals (experienced in sheds, wood chalets but not boats). They've referred to the soliftec PDF http://www.soliftec.com/Installation.htm They've removed inch-thick granite previously used as the back board and found scorch marks (turns out there was a crack in the granite). Replacing with 3x5mm fire proof board. Distance to back of stove will be just under 70mm / 7 cm. They say the recommended is at least 50mm. Does this sound right? On the PDF it suggests at least 600mm away, unless protected by a panel (which of course mine will be). Tell me I'm being unnecessarily anxious please?!

OK - a bit churlish not to try to help with a link perhaps so I've spent a moment searching on my PC. The insulation I used back in 2012 on a different flue (not the SF stove one) was this (below), from a firm called Advanced Insulation Manufacturing (clickable link to their home page). 108mm Bore, 25mm Wall Sager Glass Wool Section, 1.2m Long. Cost should be around £35 for two lengths. It doesn't look as though exactly the same stuff in this sort of id size is on their website any more but there may be alternative high temp types. I suggest anyone wanting to do this has a word with them - I seem to remember the fellow I spoke to was very helpful. If the test you do shows that an insulated flue really does make an improvement in fuel consumption while retaining a sufficient overall heat output in a boat installation (The Soliftec report suggests it will!), please do post your results on CWDF! Richard

Well - I am probably the world's slowest shell fitter so no, it still isn't finished and I still haven't done my tests. Many higher priorities will come first so I have to suggest that others have a go at this rather than wait for me! Have a read of the Soliftec test report and see what Glyn Hughes did, then repeat his tests both with and without adding some appropriate high temp capable large pipe insulation to a conventional single skin flue. You'll have to source this insulation carefully using a Google for suitable suppliers of the right stuff and only do it if you are very clear that you know what you are doing!! Any old pipe insulation is definitely NOT a good idea!! Without doing a lot more checking for a similar supplier to the one I used for a different job back in 2012 I'd rather not provide any links here. Sorry! Richard

The Soliftec sketch is a precis of BS 8511 and therefore gives a subset of 8511's recommendations ie not all the possible arrangements that 8511 recommends. You have to read the full doc to see which would work best for you, assuming you feel you want to work to it, as recommended, not required by BSS. Unfortunately getting to read BS 8511, as with any standard published by British Stds is not straightforward. You could buy a copy or borrow one if you know some organisation that will lend it. The way I do it is to join Manchester City Library. It's free and anyone in UK can join (I live in Sussex!) Once you've joined (simple online procedure), MCL allow you to link to British Stds Online (BSOL) via their website for free and then you can read almost any BS or ISO (you can't download or print them). Very few libraries now do this because of the costs and rules imposed on them by BSOL. Richard

Yes and later in his thread I advised that his info was incorrect (see post #14 in that thread). Insulated flues are recommended by the non mandatory BS 8511 code of practice and the BSS but they are not compulsory. Nor are they a requirement of the RCD. It is possible that insurers may require new installations to comply with BS 8511 but this would need to be checked with individual companies. The report linked to by Mac of Cygnet has always intrigued me. It was written by Glyn Hughes, the information officer of Soliftec. At the end he asks for "Real People" (whoever they are!) to write to him with their thoughts and experimental data on this subject. Perhaps some of us should!! Richard

I only linked to the Soliftec report because the OP asked, and I remembered this had been discussed and linked to previously. I did say that I haven't got an insulated flue. I have a stainless steel single walled one, and have no intention of changing. I also have no trouble keeping the stove in all night (and sometimes a lot of the next day) burning only wood on a bed of ash at the base of the stove, as a true woodburner.

I'm another one who has read the report Mac links to above and I also find it intriguing that the "common sense" view about heat from flues many of us have (like Alan de E) may not be right. The report was produced by a Soliftec staff member so ought to be well researched. Soliftec are the outfit that have made public the famous sketch on how best to install a stove on a boat which is here. Unfortunately, as I've said before, the Soliftec sketch is a precis of the (non mandatory) British Standard CoP BS 8511 and does not give all the options for stove installation on a boat. The only way to get the full works is to try to get access to BS 8511 itself eg by checking whether your library can provide that (it's how I've been able to read it!). There are other ways but paying the £150 or so for it from BS themselves might not be a preferred route! If you do get a chance to read a copy of BS 8511 you'll know all there is to know about boat stove installation! It's 35 pages long and full of drawings and tables. Richard

Hi Gavin, I took my stove out to replace the floor underneath it back in October. Did lots of research on correct way to mount stove, heat proof surrounds, hearth etc etc. Have you seen the soliftec handout? http://www.soliftec.com/Boat%20Stoves%201-page.pdf As suggested above it is far too large a subject with too many variables, and a lot riding on not getting it wrong, to start offering advice. But happy to try and answer specific questions if you have any... One thing I will say from doing mine, is don't assume that the last installation was done right! I spent a long time assuming that they would have known what they were doing and that it should therefore go back in the same way, only to find out (luckily before I refitted it) that there was a much safer way... Like I say, feel free to come back with questions...

Once again, this is where a look at the full BS 8511 document gives much more info than the Soliftec drawing which is just a precis of it. The Soliftec drg at least is free to look at but 8511 either costs an arm and a leg or requires you to go through many hoops to get access to a copy! From my studies of it (after I went through the hoops!), there is a trade off between hearth area size and upstand (lip) height. The upstand can be zero for 225mm distance from hearth front edge to stove front, but if it is increased to 12mm, 25mm or 50mm the hearth front edge to stove front distance can be reduced to 200mm, 150mm or 100mm respectively. Richard

We bought the 'Pipsqueak' stove (next size down from the hobbit) and used their Flue kit - it was however on 3" and in stainless steel so not a like for like comparison. Because of the size of the grate on the Pipsqueak, it apparently falls below the minimum size quoted by EU regulations and therefore installation and use is 'free of rules' (we did install it generally in accordance with Soliftec guidelines)

Has anyone used this? Have just purchased this as it will fit my 4kw arada nicely although surprisingly only the flue exiting the cabin is twin wall. They state that this is in accordance with the code of practise BS 8511:2010 but soliftec claim that to conform, both inside and outside should be double insulated! I know the code is not mandatory but this is a little confusing! The link is here http://salamanderstoves.com/portfolio/canal-boat-stove/

Salamander stoves are correct! BS 8511 does not require the flue to be double skin insulated all the way down to the stove, only the bit at the top that starts 150mm below the roof lining and goes through it up to and including the chimney outside. The rest of the flue from there down to the top of the stove can be single skin uninsulated. BUT, and here there is IMHO a flaw in the published document (which I pointed out at the comment stage!!), it says the single skin bit should "preferably" be no more than 1m long - of course it would need to be at least 1.5m long to reach the top of the stove in a normal boat. I keep saying this on here but remember BS 8511 is a document 35 pages long and explores quite a range of options that it considers are safe under different installation arrangements. The Soliftec drawing is an excellent precis of BS 8511 but does necessarily leave out many of the possible options and also, I have to say, looks somewhat unlike most canal boat installations! Soliftec have however done tests that they say show the application of a double skin insulated flue can save fuel costs due to being able to operate a boat stove at a lower burning rate without it going out due to lack of draw from a single skin flue/chimney. Why not have a word with the Salamander tech people and get them to explain the background to the design of their flue etc. I found it was useful to do this with Arada when I bought their Hamlet stove and was concerned about a number of things that were then still up in the air during the drafting of 8511. Richard

Getting ready to put my stove back in place after taking it out to re-floor the saloon. Trying to swat up on regs re hearth, fireboard, etc... It's a valor willow 4kw stove. There have been many references to the Soliftec PDF, but it seems that the link on the website is broken: http://www.soliftec.com/Boat%20Stoves%201-page.pdf Can anyone confirm that this link is not working? If it is would you mind pinging a copy of the pdf off to tomrichmond at gmail dot com... If not working does anyone have a copy saved on their machine? I have read through a copy of the draft BS8511, (I understand there are a few changes in the final version). From the BS doc, and from the manufacturers spec from my stove it seems I need a 5" hearth of non combustible material. This seems frankly insane. I am sure that my stove does not heat up the floor below it above a temp of 100degC, therefore I am sure that I could get away with a 12mm non combustible hearth... However the stove has not been tested to EN 13240, so my assurance would mean diddly squat! I currently have no floor, so I could relatively easily do away with the combustible material altogether, and just drop a slab in on the steel bearers, and bring the floor in to meet that, but it just doesn't make sense!!! Can anyone help? Do the regs on hearths remain so crazy in the final BS doc? Lastly, the section below is taken from the end of the draft BS doc. I would have said that at least three of these four things are pretty common practice among liveaboards. Would an insurance company be able to use this as a get out if they could prove you had engaged in these practices? Never * Leave the craft unattended when the solid fuel appliance is in use * Refuel the fire of the appliance when retiring for the night * Operate the appliance with the door open, except for refueling and removal of ashes * Fill any petrol tank or replace gas bottles when solid fuel appliance is in use.

The link you found is from the Soliftec website and this is a precis of the requirements given in BS 8511. As a precis it doesn't describe all the variations and options that are in the full document. Hopefully if you find a good installer, they will know the full scope of the code of practice. Soliftec have also carried out an experiment to try to quantify the benefits of an insulated flue. An unexpected conclusion of this is that having one can save you fuel. This arises from their view that stoves on boats with an uninsulated flue generally have to be run hotter (ie draught controls opened wider) to ensure enough air flow to keep the stove burning and not going out. With an insulated flue, the better flue draw allows the stove draught controls to be shut down more, still giving sufficient heat but without it going out. While I've seen a copy of their paper (if you email them they will send it to you) I'm still a little sceptical about their study and will be doing my own experiment one day! Richard

Thanks. Single skin flue it is. I was looking at the Soliftec guide and it says insulated flue pipe so wanted to see if it is really necessary.

Thanks for your reply. I did not know that insurance companies needed an out of the water survey to be carried out. It's good to know. As mentioned previously, I do plan on getting the boat out of the water and surveyed before deciding to purchase it. I do not believe the mooring comes with the boat. I have asked the seller. Also, thanks for the Soliftec guide.

The soliftec guidance, attached, gives recommendations for the heat barrier between a stove and combustible materials, and is sensible to follow. The guidance relating to twin skin insulated flues inside the boat is not. installing-stoves-on-boats.pdf

The only things 4 different BSS inspectors have ever looked at in relation to my stove installation were: secure fixing to the floor; I think the first one put a smoke pellet in there to see if it was drawing and there was any spillage into the boat. One noticed that a blanking plate on an unused flue outlet was starting to come away and gave me an advisory for that. That was it. All you can do is try to follow the stove manufacturer's advice as best as you can within the limitations you have on a boat. You won't achieve a 3.5m - 4m minimum combined chimney & flue length for example, which is what many stove manufacturer's call for. Plus go through the document that Alan has posted. So do what you can to make it safe and then stop worrying.... Edit: Actually, the only thing I disagree with in the SOLIFTEC document that Alan posted is the bit showing a cemented joint in the flue pipe. Best practice is to have a one piece flue and not to have any joints inside the boat (other than the one to the stove). Fire cement is brittle. The boat might hit a lock wall hard and a joint in the flue becomes loose without anyone realising that it's emitting CO into the boat. You shouldn't be relying on a CO detector/alarm. That's your last line of defence.