Opening up a fireplace from gas fire to wood stove, old stone house - Builders opening

[Stevec678]

Hi

I am replacing a gas fire with a wood stove and after much research and looking at many forum posts seek advice as I'm not sure what exactly is going on with my situation.

The house is stone built 1904, the chimney is on a gable end, rubble style finish externally. Internally it is lath and plastered finished. Behind the gas fire surround brick can be seen but looks to be infill to allow the gas fire install. On close look it may be there have been two occasions of recess reduction. At the far extremes close to the plaster on the picture 1, stone uprights can be seen, these are 47" high with a 42" span. These may or may not have been more decorative in the past and been hacked back to allow a plaster finish and small fire...

The plan is to install a concrete lintel across these uprights, remove all infill to make the recess for a wood stove, final finish dependant on type of surround we end up with.

Queries though, I thought I could see a brick arch lintel sitting back a little when looking internally, the upright bricks can be just seen behind the laths on the right of centre in pic 1. However, now the fire has been removed, I removed more plaster from the laths to the left and there were no upright bricks there, just a large stone butted up to the bricks to the right. Looking up behind the laths it looks like stone continues all the way up, including above the bricks at the top to the right. Looking to the edges of the stone uprights in the gaps made I can see the stone wall. I should mention, there is no room projecting chimney breast, all recess and flue is within the stone masonry wall. Is it likely there is no single lintel?

Can I take out the course of bricks above the stone uprights and fit a 1300mm concrete lintel to cover the 1060 (42"") span? A couple of the bricks on the RHS look higher than the upright so will have to come out first as well to enable the lintel to go in.

It is about 75mm course so can I pack it the lintel with mortar to provide the support or should I use slate as well.

On first seeing what I thought was brick arch (with bricks similarly coloured to the chimney stack) I assumed I had a brick chimney, from the description provided is it more likely it is simply a flue within a stone opening in the main stone walls with just an external brick stack at the top of the gable?

Thank you very much for any info.

 

[ted456]

Can you take a photo showing the whole fireplace wall from left to right, and a pic from outside the wall showing any external chimney breast up to the chimney stack? If no c/breast can you simply pic the wall?

You have been very lucky with that dangerous gas fire installation - do you have any other gas fires in the house?
Is there a fireplace or chimney breast in the room above?

Do you have the installation dimensions for the wood stove you've selected?

 

[Stevec678]

Photos provided. There is no external chimney breast and there is also a two storey extension so the pics are of the identical other side. It is rubble masonry wall up to the gable then a chimney stack. there are 4 flues, 2 each side and was essentially a 2 up 2 down so a fireplace in each room. Only 1 fire exposed which is this gas fire (now removed), others are blocked.

I do have the dimensions for the stove. 450mm wide, 350mm deep and 560mm high. Recommended min 50mm air gaps but obviously going for larger.

Never liked the gas and hardly used it the time we have been here, concerned with your dangerous installation comment so glad it's gone. How was it dangerous. Thank you.

 

[dontbelieveawordofit]

the simple answer is yes you can fit a concrete lintel.
at some point the opening will taper in . look up to see where and set the lintel just under that point.

 

[dontbelieveawordofit]

Photos provided. There is no external chimney breast and there is also a two storey extension so the pics are of the identical other side. It is rubble masonry wall up to the gable then a chimney stack. there are 4 flues, 2 each side and was essentially a 2 up 2 down so a fireplace in each room. Only 1 fire exposed which is this gas fire (now removed), others are blocked.

I do have the dimensions for the stove. 450mm wide, 350mm deep and 560mm high. Recommended min 50mm air gaps but obviously going for larger.

Never liked the gas and hardly used it the time we have been here, concerned with your dangerous installation comment so glad it's gone. How was it dangerous. Thank you.View attachment 202098 View attachment 202099 View attachment 202100

dangerous? how he can tell from those pictures is anyones guess.

 

[dontbelieveawordofit]

are you fitting the burner yourself?

 

[Stevec678]

dangerous? how he can tell from those pictures is anyones guess.

Yes, hence the concern. We rented the property out for a few years due to work commitments and the gas fire and boiler were serviced and certificated as required in Scotland each year so was wondering if there was anything obvious in the photos (other than it has been moved, gas was capped under the floor boards near the alcove where it split from the gas meter on entry so well away from the fireplace, but the pipe at the back of the fire hadn't been cut for removal during that photo).

Thanks for the confirmation on the lintel, it's hard to see up inside with such a small opening at present but it is clear that is infill as essentially there is an V shape of brick/infill below the flue that meets inverted V of the taper. This appears close to the height of the stone uprights.

What is the method of supporting the stone wall/chimney above whilst the lintel is installed.

 

[denso13]

the gas fire and boiler were serviced and certificated as required

Perfectly fine if serviced properly each year, the flue pull would have been checked as part of that. Nothing in the photos suggest it is dangerous.

 

[denso13]

What is the method of supporting the stone wall/chimney above whilst the lintel is installed.

A Strongboy or similar. If the brickwork is sound above the proposed lintel position you may get away with just cutting a slot for the lintel and sliding it in and fixing with no support. You can then remove all the unwanted brickwork below it. The lintel doesn't support all of the force of the wall above it, jut a triangular section. Use the Strongboy if unsure.

 

[Stevec678]

Thanks for the replies. There is no decent brickwork higher up the wall though, the only brickwork is what can be seen, all else is stonework. The concern is the lintel low down was installed to service a gas fire install but there appears to be no Builders Opening Lintel higher up in the stonework. Assumption is there was something across the stone uprights but why remove this if it there was there? Otherwise is the "part brick arch butted to a large stone" to direct forces into the side walls enough. Thanks for all replies so far.

 

[dontbelieveawordofit]

there’s usually a flat steel bar somewhere higher up .but if not it shouldnt need supporting really as like i said they normally taper inward the higher up you go.

 

[ted456]

Stevec678,

Thanks for the pics.

You have two flues, one seen and the other from the room above - two terminal pots can be seen on the stack.
Both flues are in a chimney breast thats been built into the thick, stone, gable wall, and goes up to the stack.
I've no way of telling but I would have imagined that the chimney breasts at both gables were totally brick built from ground floor to stack?

Why dont you slide in a Strong Boy into the bed just below that last course of bricks - and then remove all the infill?
That will give you about 50" in height - or find the install dimensions of the burner you intend to use and work to them?
And also remove all plaster on the RH side & the LH side, say 300mm past where the plaster ends now?

There's no lintel higher up. What the nonsense about flat bars in the flue means who knows.

Ignore the dangerous ignorance of those who dont have knowledge, training or experience. Not only was that installation potentially dangerous but it was a red alert for any other in-situ appliances or fireplaces - hence my questions.
Whatever kind of appliance you use in future in this or any other fireplace you would be well advised to have the flues first swept and smoke tested.
Given how the c/breasts have been constructed and given whats in your pics then why not also have the flue camer'ed?

Are you aware of the Regs ref installing an appliance? eg the hearth material and dimensions?

 

[dontbelieveawordofit]

Stevec678,

Thanks for the pics.

You have two flues, one seen and the other from the room above - two terminal pots can be seen on the stack.
Both flues are in a chimney breast thats been built into the thick, stone, gable wall, and goes up to the stack.
I've no way of telling but I would have imagined that the chimney breasts at both gables were totally brick built from ground floor to stack?

Why dont you slide in a Strong Boy into the bed just below that last course of bricks - and then remove all the infill?
That will give you about 50" in height - or find the install dimensions of the burner you intend to use and work to them?
And also remove all plaster on the RH side & the LH side, say 300mm past where the plaster ends now?

There's no lintel higher up. What the nonsense about flat bars in the flue means who knows.

Ignore the dangerous ignorance of those who dont have knowledge, training or experience. Not only was that installation potentially dangerous but it was a red alert for any other in-situ appliances or fireplaces - hence my questions.
Whatever kind of appliance you use in future in this or any other fireplace you would be well advised to have the flues first swept and smoke tested.
Given how the c/breasts have been constructed and given whats in your pics then why not also have the flue camer'ed?

Are you aware of the Regs ref installing an appliance? eg the hearth material and dimensions?

tell us the regs.

 

[Stevec678]

Ted456

I had assumed the chimneys were brick built from the ground floor up but info presenting itself at the moment suggests it is embedded within the stone and only the stack is brick built. I have see the gables during the extension build (within the last 5 years) externally and internally in the loft and there is only stonework to be seen. All other fireplaces were filled in during works in 1996, this fireplace flue was relined to the then standards. I understand its difficult to assess from the photos provided.

I have previously seen behind the plaster on the sides and it is stone wall, I can see the wall next to the RH side lath and the stone wall is also visible. I have removed more plaster vertically over the centre of the opening and it is just stonework there. I have the dimensions of the burner, if we opt for a limestone surround I will need a 36" by 36" opening, otherwise it would be an opening to the stone uprights already situated with a decorative mantle (requiring twin wall if too close).

The constructional hearth is non-combustible (stone with concrete layer, this was seen when the floorboards were up for the gas pipe removal) approx 200mm deep and projects just over 500mm from the wall so within regs. Distance to combustibles wont be an issue with the dimensions presented and aiming for.

The main query concern is there appears to be no structural brickwork on the front chimney leaf so to speak (I can't see the rear wall clearly but behind the gas fire brick back it looks to be stone work again), with a stone and brick mix course at approx 57" then purely stonework above that. TBH, it was not what I was expecting, as stated had assumed there would still have been a brick built chimney.

I would stick a strong boy into the mortar bed but unsure which if any brick course its worth doing it in due to the final course layer being as described - part brick soldiers butted up against stone. I will upload some close ups to see if it can be see.

If you could be so kind as to state why the gas installation was dangerous I'd really appreciate it. The flue will be smoke tested and cleaned before installation of a steel liner, although as stated it was relined during renovations and alterations in the 90's. Even if good it seems the general advice is line with steel flexi to aid more modern stoves. Thanks again.
First pics shows the far left brick meeting stone. Pic 2 is the stone to the left (hard to see). Pic 3 are the bricks to the right. One course, mixed stone and brick? Appears to be final course of any bricks seen.

 

[dontbelieveawordofit]

What the nonsense about flat bars in the flue means who knows.

if you knew the slightest thing about what you were talking about you’d know there’s every possibility there’s a 10x50 or similar iron flat bar in that brick or stonework from the original builders opening. you clearly have no constructive input other than to state obvious facts that are totally irrelevant to what the op’s queries are. bob