Opening a fireplace and fitting a stove

[Bilabong007]

Hi,

Hope to open a bricked up fireplace with the intention of fitting a multifuel burning stove. Started looking at it today and took off some of the plaster to find what's in the pictures

Untitled

• Bilabong007
• 6 Jul 2014
• 1

Untitled

• Bilabong007
• 6 Jul 2014
• 1

Can someone help with sizing up the opening a showing where the edges are. I hoped it would be obvious but I'm not really sure what I'm looking at.

Any advice much appreciated

Graeme

 

[Norcon]

I just tore out a big hole and then poured concrete into a form.....
http://tinyurl.com/mcgefs7#

That's it sitting ready for the pour. Edges didn't really concern me as I made new ones.

This is the finished product....
http://tinyurl.com/nuy7qn4

http://tinyurl.com/mus75qs
That's it part way through the digging. It hadn't done a fred dibnah at that stage. Just me on the breaker.

 

[Bilabong007]

Won't show the mrs pic 3

I thought the lintel and brick lining would be obvious on mine

 

[Norcon]

I can delete 3 if you want.


Have to admit it was a real bomb site for a while.

 

[saladdays]

I'd remove a bit more plaster to see the bricks. Then you can work out what to remove. I've done something similar. Ripping out the old lintel and opening it right up. My chimney breast is 6 bricks (1.37m) wide. This is my effort: //www.diynot.com/forums/your-projects/opening-up-a-fireplace-and-installing-a-stove.379469/

PS. spray with water to keep the dust down.

Edit: http://www.stovefittersmanual.co.uk/articles/opening-up-a-fireplace/

 

[Bilabong007]

Well I opened a bit more when the wife went for a haircut.

Found this

Untitled

• Bilabong007
• 2 Aug 2014
• 1

Untitled

• Bilabong007
• 2 Aug 2014
• 1

Untitled

• Bilabong007
• 2 Aug 2014
• 1

Untitled

• Bilabong007
• 2 Aug 2014
• 1

Untitled

• Bilabong007
• 2 Aug 2014
• 1

Looks like a precast flue of some sort. Anyone got any experience of these and what to do from here?

Flue ID - 200mm

Opening;
345mm deep
650mm height to lintel
810mm height to flue
400mm wide at throat
550mm wide at lintel

Should I be looking at removing the lintel and fitting something else to give space?

Any advice appreciated

Graeme

 

[Justin Passing]

It would be a good idea to test the thing at this stage.
It might be a flue that was made by pouring concrete around a sausage down the middle - not a method which is approved now, because of problems I'm not clear about. You can still use them though, if they're in good order

Get some smoke pellets (Plumbers merchant) at least 5m³ 30 seconds type. You'll need a few. Don't get red smoke ones - easy to see but they stain things.
Warm the flue (blowlamp for a minute) then light the pellet under it. A foot below the edge, say. All the smoke should get taken up, and out of only the right chimney pot, without getting into any other chimney through the feathers, or into any room or the loft. You'll need a few pellets while you run about. Binoculars are useful.
You might want to start with smoking paper in case it's blocked . If it won't pull, try warming it longer. If it still fails get it swept, (which you'd have to do anyway). Spiders webs can be a pretty effective blockage

If anything's wrong you cannot just line it.
If you don't have to line it, you still need the right sort of termination/pot.
Check the Manufacturers instructions for your intended stoves, for chimney and opening requirements. Only an approved geezer who knows his chimney/flue stuff, should install the thing and retest the flue.

 

[Bilabong007]

Thanks justin,

From the look of the twigs poking down and debris at the bottom I will get it swept first and go from there

If it's lined in concrete and draws ok maybe I can do this without lining, but just fitting a cowl on the open pot. Don't know how BC would feel about that?

Graeme

 

[Justin Passing]

Ooh missus, no cowls, though I don't know owt about multifuel stoves specifically. Look up the stove instructions, they're probably online. It'll refer to BS flues or "Classes" of chimney.
I imagine instalation of anything which might kill you has to be done by someone registered (as would be the case with gas) and "notified" to BC. BC don't get involved in whether it needs a liner themselves.
If you have to get it lined, then there will probably be a specified terminal thing to go on top. Lining isn't really a huge deal though some installers are inclined to make it one..
I'd test it before you get it swept - cheap and may show a fracture in the loft, etc.

 

[ree]

The twigs and twig debris is probably from a bird's nest or nests - you definitely need to sweep the chimney flues, and have the stack terminals examined.

Find the Mfr's dimensions for the stove you have in mind, and work to them for the new opening.

 

[Bilabong007]

Update

Had the flue swept and certified ok.

Sweep said steel lining a concrete lined chimey was a waste of money as it's absolutely fine to use.

Have read that runoff of condensation back down the chimney can be a problem if it's not flashed properly so intend using http://www.fluesupply.co.uk/en/installation-accessories/73-internal-fit-clay-liner-adaptor.html

Does anyone have any experience of getting this sort of thing passed BC?

Many thanks

Graeme

 

[stuart45]

It would be a good idea to test the thing at this stage.
It might be a flue that was made by pouring concrete around a sausage down the middle - not a method which is approved now, because of problems I'm not clear about.

Are you sure about that, as there are still firms where I live using the method of a lightweight concrete liners.

 

[Bilabong007]

It would be a good idea to test the thing at this stage.
It might be a flue that was made by pouring concrete around a sausage down the middle - not a method which is approved now, because of problems I'm not clear about.

Are you sure about that, as there are still firms where I live using the method of a lightweight concrete liners.

That's essentially what the sweep said: two options for lining a brick chimney
1. Cheapest: steel liner - 20 or so years out of it
2. Expensive: concrete liner - 50 or so years out of it

Turns out I have a concrete liner that was put in when the house was built and has never been used. Would seem silly to re-line a liner.

My issue is whether Building control will see it that way and how the expansion from a 125mm to 200mm pipe will affect the stove.

Graeme

 

[stuart45]

You won't need BC if a HETAS fitter installs it. That's a pre cast flue system such as Isokern. The dove tail brick you took out is for access to flaunch the fireback.
A liner the correct size is more efficient for the stove, but can last only a few years if you burn wet wood on a slow burn.

 

[Bilabong007]

Would like to diy it if poss and therefore must run it through BC

It looks like its concrete pots stacked on each other. Any idea if/what the void behind this is filled with?

I would like to take out the lintel but don't want half a ton of sand in my living room if possible. Should I drill a hole in it or? Before breaking it out

Many thanks

Graeme