woodburners. we need some.

[tycarregydwr]

I know a bit about woodburners, we bought a lovely one for our previous house. In our current project we currently have two open fireplaces. They have hideous 60s tile surrounds, and the fireplaces themselves are quite small and shallow, designed for coal I guess, not wood. We plan to fit woodburners in both - I know this isn't period, but on this there's just no way we can sacrifice the efficiency for historical accuracy. And my understanding is that running a woodburner will be good for the house from a ventilation/damp/etc perspective. Having not considered period property things with regard to woodburners before, I would appreciate any thoughts, advice, lectures, and opinions!

In our previous house the fireplace had been all walled up, when we had it broken open luckily the original brickwork arch was high enough to accept the stove we had so it was a simple matter to fit. Given that these fireplaces are so small, it won't be as straightforward. Does anyone have experience of enlarging old fireplaces in order to set stoves in?

We haven't decided what kind of burner we are looking for yet, we are thinking about getting another one from the company we had before as we really loved it and it's good value (definitely not period though!), though having had a trawl around ebay I'm somewhat tempted by a range with cooking facilities if one could be found to fit our budget.

So, sorry to be asking yet another broad question, but all contributions on stoves, styles, sourcing, fitting, and so on, would be most welcome.

 

[plasticpigeon]

Usually behind a fireplace there is a builders opening of some sort. Sometimes these are about the right size for an insert, and sometimes quite big, perhaps 5 feet or so which would then have had extra bricks built into it to accommodate an insert of the correct size. When you rip out the current fireplaces there may well be a constructional arch just right for what you want already there. I know nothing about stoves, but am looking forward to getting the fireplace back into my front room, I think they look so much nicer. On a slight digression, Stovax make a solid fuel insert with a convector fan that blows hot air heated by the fire out of a small slot in the insert. Has anyone used one of these, they claimn them to be much more efficient than a simple open fire

 

[tycarregydwr]

That is very helpful information, thank you so much. I can't wait to get rid of the tile monstrosities!

 

[88v8]

Clearview and Esse both make good-quality woodburners, either freestanding or as inserts in a fireplace.
http://www.clearviewstoves.com/
Clearview better quality.

The choice will depend to an extent on room dimensions/heat losses blahblah, but try to choose two that take the same log size. It is not efficient to feed a large stove with short lengths, and it will save a lot of logistics compared to running two different-length woodpiles.

Btw, depending how long ago your previous installation, there may be a lot more hoohah now about t'Regulations...

Ivor

 

[tycarregydwr]

Thanks. You make a good point, but we will definitely be getting two different sizes as they are for very different room sizes. One is a small, self-contained sitting room (currently has an open fireplace but no radiator), anything more than 4-5 kw would be overkill, and the other is a much larger space in the middle of the house (open fireplace, also has radiators) so we're planning on at least a 9 or possibly 11 kw stove here with the aim of warming much of the house that way. We were looking at a cute 11 kw stove that is cheap for now, and thinking that in a few (many?) years' time when finances are different we could think about upgrading to something more powerful with a back boiler.

Our previous installation was not even 3 years ago, so I don't think much has changed in that time? Though I thought that we'd have slightly fewer restrictions now, as we are not in a smoke-control zone as previously.

 

[AMc]

Stovax make a solid fuel insert with a convector fan that blows hot air heated by the fire out of a small slot in the insert. Has anyone used one of these, they claimn them to be much more efficient than a simple open fire

My parents had a "jetmaster?" open fire with a mechanism to circulate air around it to reduce loss up the chimney. It didn't work well and they got rid of it for a stove.
On the advice of the installer they didn't attempt to set the stove into the fireplace opening as this means 3 or the 4 sides radiate heat into the stack (a great big thermal mass). By setting the stove slightly proud they were able to fit a lower capacity stove with roughly the same thermal output.

so we're planning on at least a 9 or possibly 11 kw stove here with the aim of warming much of the house that way.

Building regs will insist on an air brick or vent for anything over 5KW (IIRC) regardless of how draughty (or not) your house may be already. This is a protection against CO poisoning and any HEATAS installer will be unhappy to install a bigger stove without the regulation vent as it won't comply.

In general it's recommended to burn a smaller stove at a higher temperature than a large stove "idling" as the hotter burn gets more heat per Kg from the wood and the hotter flue gases reduce condensation which results in longer life for the flue liner.

 

[eezageeza]

somewhat tempted by a range with cooking facilities

We have a stove with a flat top (flue exits from behind) and although it wasn't part of the plan when we bought it, we cook on it a lot - boils a kettle in minutes, and you can obviously cook anything on it that you'd normally do on a hob. You can even do baked potatoes (wrapped in foil, in a cast iron cassserole).

 

[tycarregydwr]

[

so we're planning on at least a 9 or possibly 11 kw stove here with the aim of warming much of the house that way.

Building regs will insist on an air brick or vent for anything over 5KW (IIRC) regardless of how draughty (or not) your house may be already. This is a protection against CO poisoning and any HEATAS installer will be unhappy to install a bigger stove without the regulation vent as it won't comply.

In general it's recommended to burn a smaller stove at a higher temperature than a large stove "idling" as the hotter burn gets more heat per Kg from the wood and the hotter flue gases reduce condensation which results in longer life for the flue liner.

That's different info than we were given by the HETAS installer 3 years ago - they said it was dependant on the size of the room, and the 5 kw limit referred to the a specific room size. I will check this out again, but the area that would be heated by the stove is vastly bigger. In our previous house we had a 7 kw stove fitted, in a room that required extra ventilation, but our hetas installer said the gaps between the floorboards were sufficient ventilation and signed it all off (and it was checked by building regs guy who was there on another matter) - so I'm surprised? Maybe I've misunderstood something.

But thank you for the info about the 'idling', I will investigate the matter more.

 

[Lime]

May I remind everyone who will be using a solid fuel enclosed fire this winter about the danger of overheating cast iron?
Many older fires and flue pipes were made from cast iron, like parts of a tortoise stove for instance and maybe some new fires too.
When cast iron gets very hot (near to dull red) it is porous to carbon monoxide.
i.e. the gas goes straight through the hot metal as if it wasn't there.
Consequently very hot cast iron allows carbon monoxide from the flue gases (and only carbon monoxide, no other fumes) to filter into the living accomodation.
Carbon monoxide is odourless, colourless and deadly poisonous.

 

[MdB]

Never rely on what someone tells you when you can go direct to the regs in question.
http://www.planningportal.gov.uk/buildingregulations/approveddocuments/partj/approved

Section 2 (page 29) is what you are after. There is no mention of room size that I can see in a quick reread. I wouldn't have thought that floorboard gaps would be acceptable as they could easily be covered over.

 

[jackpoint]

Currently loving the thought that has gone into this stove.....http://www.fhtstoves.com/

 

[tycarregydwr]

May I remind everyone who will be using a solid fuel enclosed fire this winter about the danger of overheating cast iron?
Many older fires and flue pipes were made from cast iron, like parts of a tortoise stove for instance and maybe some new fires too.
When cast iron gets very hot (near to dull red) it is porous to carbon monoxide.
i.e. the gas goes straight through the hot metal as if it wasn't there.
Consequently very hot cast iron allows carbon monoxide from the flue gases (and only carbon monoxide, no other fumes) to filter into the living accomodation.
Carbon monoxide is odourless, colourless and deadly poisonous.

I didn't know that, thank you. We always have a CO detector anyway, but I will pass this important information on to my parents who have a 160 yr old cast iron stove that has parts that glow dull red.

 

[MdB]

May I remind everyone who will be using a solid fuel enclosed fire this winter about the danger of overheating cast iron?
Many older fires and flue pipes were made from cast iron, like parts of a tortoise stove for instance and maybe some new fires too.
When cast iron gets very hot (near to dull red) it is porous to carbon monoxide.
i.e. the gas goes straight through the hot metal as if it wasn't there.
Consequently very hot cast iron allows carbon monoxide from the flue gases (and only carbon monoxide, no other fumes) to filter into the living accomodation.
Carbon monoxide is odourless, colourless and deadly poisonous.

I'm going to ask for a citation for that. I'm not saying you are wrong Lime, just that I can't find any reference to this online.

Fitting a carbon monoxide detector is essential though.

 

[tobydog]

Well, it looks like an old book but then proven physics / science shouldn't date!

It's not definitive but it might help.

http://books.google.co.uk/books?id=tLMOAAAAQAAJ&pg=PA221&lpg=PA221&dq=can+carbon+monoxide+pass+through+cast+iron&source=bl&ots=-N8F5iQ0yo&sig=y7UHHSnHL_kt6Q1IjRyS_EiH4bY&hl=en&sa=X&ei=yA-AUMfBLKr64QT0pIHgCg&ved=0CDcQ6AEwBA#v=onepage&q=can%20carbon%20monoxide%20pass%20through%20cast%20iron&f=false

 

[MdB]

Well found. It is also mentioned here:
http://forum.downsizer.net/archive/cracked-top-on-woodburner__o_t__t_58952.html

I'm surprised that there isn't more on this though.

 

[plasticpigeon]

Well it only says is believed to be able to in that book!!!

 

[tobydog]

I agree which was why I thought I should mention that it wasn't actually definite. Interesting book though and quite appropriate for the 'ventilation v. warmth' thread.

 

[88v8]

A flue thermometer is pretty useful, I think.
http://www.amazon.co.uk/Stove-Pipe-Thermometer-Magnetic-Fluesystems/dp/B0071LGST8/ref=sr_1_2?ie=UTF8&qid=1350579804&sr=8-2

Saves overheating the liner.

Surprising how one's perception of how well the fire is burning differs from the reality.

Ivor

 

[agbagb]

I'm on with the same job at the moment, two (Multifuel - we might end up burning some coal) stoves in the Whitby Cottage. Once I've finished rebuilding parts of the stack ( more on that shortly) and we've got the council to let us put scaffolding to re-roof and to rebuild the top of the stack, I'll be dropping two 150mm liners down. These will be 904 grade as I don't want to doing it again in my lifetime.

We won't be adding any insulation around the flue, I can't see that it is necessary especially as the stack is internal. (We've been burning a lot of larch in our normal abode for 3 years and have no traces of creoste build up). Although I will have some rockwoll flexislab on top of the register plate just to keep a little more of the heat in the room.

The register plates I'll make from 1.6mm steel, it's fairly easy to cut with an electric jigsaw.

The Stoves will propably be from Town and Country. I like the quality and simplicity of design. They do some insets that could work well without having to change your openings. We have a "Thornton Dale" that heats our five bed house for most of the winter. I've written a bit about our experience with a wood burning stove here

As for enlarging openings, it''ll depend on what there already, making it taller is a lot easier than making it wider (normally). With proper precautions a brick arch can be rebuilt higher up. Self corbeling will hold up most of the stack above it. There might be something in this about rebuilding an arch that gives you some idea of the job.

Hope this helps