Log burner

[Gav22]

Hi.

 

I have a static caravan and would like to install a log burner. I’m capable of doing it myself, but would like to know the correct way for the flue to go through the ceiling and roof.

I will be using a 125mm twin wall flue, but need to know how much of a gap needs to be around it. Is there some type of fitting that is needed to be fixed between the ceiling, void between and roof or is it ok to fit the flue on its own.

I want to make sure that the flue doesn’t get to hot and starts scorching things.

thanks.

[2seaside]

this website may help

https://salamanderstoves.com/installing-stove-caravan/

 

Presumably you have the static on your own land - if not, you need permission from the site owner before starting. 

Bear in mind that if you are in a smoke free zone, and if you want to stay on good terms with everyone downwind of the static, you need to fit a modern clean burning stove and make sure you use properly dried kiln wood.

Also bear in mind that the extra weight of the hearth and stove combined may affect the static balance, you may need to put extra supports underneath.

ADDED:

You'll also need to check with your insurance - could be an extra premium, or could simply invalidate your insurance, especially as you plan to fit it yourself so will not have any compliance certificates.

Edited September 30, 2019 by 2seaside
missed a line

[Paul1957]

I often think it is not a good idea to put holes in a roof since good sealing against water ingress is needed. I would also consider putting the flue through a wall, this seems to be normal for houses with log burners.

[Gav22]

Thanks both.

 

its on my own plot whilst I’m building a house, so I don’t need any permissions.

Ill take a look through that site, thanks.

I originally planned to put it through the wall, but was advised against it as the flue will now have 2 bends. Due to this the draw on the smoke will be reduced and so I was told to go straight up.

[Guest]

And remember to install a good carbon-monoxide detector.

[Mr Plodd]

Log burners rely on convection currents to remove the smoke  etc, once it’s warmed up there will be plenty of heat to ensure a decent updraught. The flue is about 4” in cross section. Bends in the flue will be a max of 45° and the cross section big enough for the bends not to be an issue. Many houses have 2 x 45° bends in their log burner flues and the bends are manufactured for them so I would question the “advice” you quote. 

 

Don’t forget to ensure there is sufficient air getting INTO the static to “feed” the log burner AND be sure to have a good quality Carbon Monoxide alarm (or two!) 

 

If you don’t have a source of well seasoned timber (which is VERY important) I would suggest you check out how much it costs (delivered) then work out how long a delivery will last you. Softwood burns MUCH quicker than hardwood. I have two friends and both have multi fuel burners, the amount of timber they “eat” is pretty considerable so storage of it, as well as cost, needs to be considered. 

It’s entirely possible that gas or even electric space heating COULD actually work out cheaper in your situation. (But of course it may not) 

 

Do your research very thoroughly before committing to a log burner. 

 

Andy

[Steve05]

6 hours ago, Gav22 said:

Hi.

 

I have a static caravan and would like to install a log burner. I’m capable of doing it myself, but would like to know the correct way for the flue to go through the ceiling and roof.

I will be using a 125mm twin wall flue, but need to know how much of a gap needs to be around it. Is there some type of fitting that is needed to be fixed between the ceiling, void between and roof or is it ok to fit the flue on its own.

I want to make sure that the flue doesn’t get to hot and starts scorching things.

thanks.

 

I'm no expert but I recently researched/ installed a log burner at home.

 

First thing that comes to mind is distance to combustibles,  assuming the caravan won't be classified as 'non-combustible' I'm not sure how you'll be able to achieve the minimum gap between the back of the stove and wall?

 

Different types of twinwall have different clearances, I used Poujoulat which is 50mm to combustibles but other brands can be more than that. Transitioning the ceiling void(x2) I used ventilated fire stops, basically just spacers to achieve the gap.

 

If you go through the wall be aware that this will likely make the burner much harder to light as it'll be a 'cold' chimney.

 

I'd strongly recommend a burner with an external air supply. This gives a much better through draft, makes it easier to light and also means the burner isn't taking it's air from the room which is more efficient and a lot safer.

 

The burner is a nice feature but I don't think I'd fit one in a caravan,  just a bit too risky for me.

 

[Guest]

Talking as an ex-narrowboat owner, I'd say the air supply is better internal as this helps ventilate and dispel damp.

[Bolingbroke]

3 hours ago, Mr Plodd said:

.... I would suggest you check out how much [firewood] costs (delivered) then work out how long a delivery will last you. Softwood burns MUCH quicker than hardwood. I have two friends and both have multi fuel burners, the amount of timber they “eat” is pretty considerable so storage of it, as well as cost, needs to be considered. It’s entirely possible that gas or even electric space heating COULD actually work out cheaper in your situation.

 

Indeed. I have a wood burner (8kW) and luckily have a free supply of fuel for it.  I usually have it lit only for about 2 hours on winter evenings but nevertheless It gets through an enormous amount of fuel.  I spend a lot of time in winter cutting up wood, and if I had to buy the stuff it would certainly not be worth while. 

 

[Guest]

Consider smokeless solid fuel (briquettes) if the stove is multi-fuel.  They can burn very slowly, such that the fire stays 'in' all night.  The only disadvantage is that you need to empty the ash daily.

[Steve05]

18 minutes ago, kelper said:

Talking as an ex-narrowboat owner, I'd say the air supply is better internal as this helps ventilate and dispel damp.

 

I can understand why a 6" hole might not be a good idea in the floor of a boat but IMO  it's the way to go in a land based dwelling.  You're not burning the air you've just heated, cold direct air means a better burn, no danger of cold drafts as the fire sucks air across the room and most importantly a much reduced risk of carbon monoxide poisoning, a real danger in such an enclosed space. A cheap/easy thing to do at the build stage.

 

Still don't think I'd be happy with one in a caravan though, my wife fancied one for the garden room - it's keeping the fan heater.

 

[Stevan]

My son in law heats his house with a log burner and just spent £400 on 5 cubic metres of seasoned logs which he hopes will see him through the winter. He will still need to spend considerable time cutting/splitting them to size.

[Guest]

You can never have enough logs, but I've ran out of space to build log stores so I've had to turn my greenhouse into one..

 

 

[Paul1957]

20 minutes ago, Stevan said:

My son in law heats his house with a log burner and just spent £400 on 5 cubic metres of seasoned logs which he hopes will see him through the winter. He will still need to spend considerable time cutting/splitting them to size.

That might be not far off what our gas fired central heating costs to heat the house and water. We have changed gas/elec supplier again and the prediction is about £800 for a full year for the gas and elec. There seems to be many low offers now.

[Gav22]

15 hours ago, Mr Plodd said:

Log burners rely on convection currents to remove the smoke  etc, once it’s warmed up there will be plenty of heat to ensure a decent updraught. The flue is about 4” in cross section. Bends in the flue will be a max of 45° and the cross section big enough for the bends not to be an issue. Many houses have 2 x 45° bends in their log burner flues and the bends are manufactured for them so I would question the “advice” you quote. 

 

Don’t forget to ensure there is sufficient air getting INTO the static to “feed” the log burner AND be sure to have a good quality Carbon Monoxide alarm (or two!) 

 

If you don’t have a source of well seasoned timber (which is VERY important) I would suggest you check out how much it costs (delivered) then work out how long a delivery will last you. Softwood burns MUCH quicker than hardwood. I have two friends and both have multi fuel burners, the amount of timber they “eat” is pretty considerable so storage of it, as well as cost, needs to be considered. 

It’s entirely possible that gas or even electric space heating COULD actually work out cheaper in your situation. (But of course it may not) 

 

Do your research very thoroughly before committing to a log burner. 

 

Andy

I have already bought a carbon monoxide detector ready for it.

Ive worked out the costs between gas and logs. I’ve got about 5 tonne bags worth of logs on the site already and there are a couple of trees on site that need cutting down. I’ve hopefully got enough free wood for a few years.

Ill work out what’s best between going through the wall and roof.

 

thank you.

[Mr Plodd]

Any timber from a tree you cut down will need at LEAST a year to season (dry out) that’s why you see great piles of the stuff in so many French  gardens. Invest in a cheap damp meter (I got one from ALDI for a tenner) So you can check the water content of your firewood. Damp wood really doesn’t burn at all well! 

 

Andy

[Gav22]

Thanks Andy.

the wood I have now should last this winter and the plan is to cut the trees down in a few weeks, so they should be ready for next winter and the one after.

I should have the house built then, so I’m not to bothered about using it after that.

Ill get a damp meter and check it.

[Guest]

You won't use the damp meter once the novelty wears off, you can tell how seasoned the logs are by their weight, they get considerably lighter, feel dryer, and after a while you can 'just tell' when they are ready.

[Gav22]

Is it best to leave the logs whole and chop them when they have dried or will the dry quicker if they are chopped up straight away?

[Stevan]

24 minutes ago, Gav22 said:

Is it best to leave the logs whole and chop them when they have dried or will the dry quicker if they are chopped up straight away?

My SIL tells me that split logs dry quicker, but dry logs split easier.

[Mr Plodd]

If you have a large number of logs to split it’s well worth investing in a powered splitter, they are about £150-£200 but save a LOT of axe swinging.

 

Andy

[Gav22]

The ones I started splitting yesterday were cut around 12 months ago. One swing and they split pretty easy. I haven’t tried a fresh cut log yet, but I’m guessing they won’t be as brittle.

ill look into a log splitter.

thanks.

[ReggiePerrin]

Log burning stove in a static?  Why not?

 

Romany Gypsies always had one in their Vardo wagons, workmen in their portable messing cabins,  soldiers in their wooden barrack huts,  Fred Dibnah in his wooden caravan...  many narrow boat owners in the lounge space of 6'10" wide boat...

 

As long as it is done properly in all respects, why not?

 

 

 

 

 

 

[Wunny]

Things I've learned about our log burner.

 

They give off a nice cosy warmth, but like a baby require constant attention.

 

Ours needs feeding every hour and with 24 hour burning, the ash needs emptying every day.

 

Don't leave the ash in a bucket indoors, like charcoal, it may look like it's out, but there will be smouldering embers giving off carbon monoxide.  Take it outside and empty into a metal dustbin, not a plastic one.

 

While wood is free, it's cheap to run, but if you ever need to buy in wood, then gas is a cheaper option.

 

Over the 1st winter, I got through 3 tonnes of dried wood.  It all came free, but did require cutting to the right size for the fire box.

 

With wood, you get warm three times:

1, When you collect it.

2. When you cut it.

3. When you burn it.

 

Have fun, stay warm!

 

My log burner project

 

 

[JCloughie]

Regards fitting through wall or roof.  I know the building regs don’t directly cover mobile homes but they could be a good guide.  As you are building your own place you may already have a copy.  The regs proper can be difficult to read but there are some books which make them more accessible.

 

https://www.amazon.co.uk/s?k=building+regulations+explained&adgrpid=51600151325&gclid=EAIaIQobChMIz4mY2uT65AIVgbTtCh3zYQirEAAYASAAEgKF9fD_BwE&hvadid=259106807225&hvdev=t&hvlocphy=9045572&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=14475007868537786710&hvtargid=kwd-317738253497&hydadcr=18518_1817324&tag=googhydr-21&ref=pd_sl_32tc78u0u1_e

 

I have built many brick flues and it was believed by the ‘old timers’ that all flues need two bends for the draw.  This is rubbish, straight is best.  Sometimes we could put 4 bends in, two to pass through a bedroom at a corner or bypass an upstairs fire, and two to get through the roof in the desired position.

 

However, I believe the minimal amount of bends needed would make a negligible difference.

 

The flue supplier will do a ‘slate’ (I think that they still call them hat), for flat roofs.

 

John