Flue without chimney stack.

[Guest Gimlet]

I'm not to worried about that. I've been in the building trade a very long time and I know I can reinstate a roof covering around a flue flashing without leaks. But before potentially putting in an offer, I want to know that I can exit a liner from a chimney stack that's within the roof space without falling foul of regulations.

[Dan Maynard]

We did it the other way round, kept upstairs and top of chimney stack supported on a steel. (In the 70s renovation they rebuilt the lounge chimney with no foundation, oak mantel exposed to flue, and was leaking enough to burn rafters.)

 

Now we have insulated solid flue going from stove up between rafters and up a little way into the old stack, then transition to uninsulated Flexi liner up the old stack through roof and to top of chimney.

 

I'm not an installer but sounds like there should be an answer to what you need, maybe insulated through the roof.

[Peasgood]

I'd say insulated through the roof was best option. 

Sounds like you are as experienced as any already though. Son had "reputable" firm fit insulated through a slate roof and they made a right balls of it. 10 gallons of silicon and it still leaked.  

[dumper]

12 hours ago, Gimlet said:

I'm not to worried about that. I've been in the building trade a very long time and I know I can reinstate a roof covering around a flue flashing without leaks. But before potentially putting in an offer, I want to know that I can exit a liner from a chimney stack that's within the roof space without falling foul of regulations.

So look on product website see what joints are available for liner to insulated flue how will you hold it up to clear the pitch on the roof ?

[Guest Gimlet]

58 minutes ago, dumper said:

So look on product website see what joints are available for liner to insulated flue how will you hold it up to clear the pitch on the roof ?

I'd fix the rigid flue to the brickwork of the stack in the roof-space using a plate and clamp and flaunch it in, as you would on a conventional installation for an over-roof stack. I wouldn't like the idea of the brick void remaining open in the loft when there's a live liner in it. Anything could fall in/build a nest.  

 

Failing that, I'd fabricate a steel bracket and fix it to the rafters from underneath. HETAS consultation first though. 

If I did put an offer in, there's a good bloke locally who I'd buy the stove from and get to do the install signing off so I'd get him in for a discussion before completing. 

 

It would exit near the ridge and there's no taller structures or windows anywhere near so 1.8 m above the ridge should be ample.

Edited January 3, 2023 by Gimlet

[Sugarshaw]

Hi there, new member just registered 

I’m hetas, and yes you can fit a liner upto the top of the stack, then twin wall through the roof. 
Iv done two installs like this before, you need an anchor plate which clamps onto your flexi liner, then screws down onto the top of the stack, and has a twin wall coupling on top. 
you then need 600 above the ridge if you land within 600 of the ridge, you could always use a couple of 45 bends to kick it to one side. 
hope that helps! 

[Guest Gimlet]

On 08/01/2023 at 21:33, Sugarshaw said:

Hi there, new member just registered 

I’m hetas, and yes you can fit a liner upto the top of the stack, then twin wall through the roof. 
Iv done two installs like this before, you need an anchor plate which clamps onto your flexi liner, then screws down onto the top of the stack, and has a twin wall coupling on top. 
you then need 600 above the ridge if you land within 600 of the ridge, you could always use a couple of 45 bends to kick it to one side. 
hope that helps! 

Cheers Sugarshaw. Top man. 

 

I'm still going to view this property but I've put an offer in on another one. Slightly different proposition. It's a 1950's house which was fitted from new with a gas stove in the living room. There is a brick flue which is 18" brick work external dimension (so 9-10" internal clearance). I've inspected the roofspace and it appears to be a vertical drop. Stack exits near the ridge and is about 2' above ridge height. 

There won't be a fireplace within the chimney breast in the living room but if I buy it, I'm hoping I can fit a stove onto a stone hearth into the room and, fill in the space where the gas stove was and pass a twin-wall vitreous flue through the wall and up the brick flue to the top of the stack. 

 

I'd also like to put a wood-burning stove in the kitchen, but that would need an external flue up the side of the house. Just wondering how high that would have to terminate above the eaves and the other complication is the house has been fitted with external insulation, so the flue would have to pass through that and somehow be made good.