Inglenook fireplace blocked, cold

[Keith]

Thought to be 1640s, Lincoln, at street level but the 1640s thick ( one or two metres?) brick wall acts as retaining wall against the one floor higher ground level at rear of house. Any info welcome, but especially two current concerns:
A) About three metres up chimney is brick rubble, seemingly to block chimney and/or support the 1880s cast iron range still existing on first floor. It looks ready to fall on anybody touching it with a pole and standing in the chimney on ground floor. But most likely it has for 160 years hovered stuck, probably deliberately, at the top of Venturi fluting. Would be great to be able to have open fire on main floor again. Oh - grade 2 listing....
B) That wall can be estimated to weigh 100-200 tons. Daughter moving into house, initially at 8C interior air temperature, and we find that 10 days blasting all radiators 24/7 brings the surface temperature of the brick up to around 14C to 17C. Maybe that explains why previous owners installed installing interior walls blocking the fireplace and wall. Ideas please?

 

[Cubist]

I do hope that second photo is one looking Down and not Up?

 

[Keith]

Nope. Looking up from inside ground floor Inglenook and hoping the bricks will hold for 160 years and 30 seconds.

 

[Kearn]

They look sooted on the face, so presumably the bricks have come from within the stack somewhere…?!

The fireplace above, is that now using the flue previously for this fireplace or a separate feathered flue?

 

[Keith]

Oddly, Gemini AI manages to sound very knowledgeable about Inglenooks blocked with random or corbelled bricks. Gemini claims that it was standard in the 1860s, when installing a maybe 350kg cast iron range, to partly support it on that rubble plug. Also, the brick plug could enhance the then-novel Venturi fluting to produce partial vacuum. That was needed to perform the trick of dragging the exhaust heated air/fumes/smoke from the range's fire downwards (!) and past the oven and water heater portions of the range, then upwards out the chimney. Gemini also was happy to advise me to poke the plug of random bricks with a pole, though inaccessible from above through the range. The charitable interpretation is that Gemini was confused by the different US and British meanings of 'first floor cast iron range'

 

[Keith]

They look sooted on the face, so presumably the bricks have come from within the stack somewhere…?!

The fireplace above, is that now using the flue previously for this fireplace or a separate feathered flue?

Believed to be same flue, though eg Gemini AI claims that a wide enough 1640s flue might end up divided into two in the 1860s. Once I and the neighbours have renewed our life insurance policies, I might pick up the angle grinder and find out. Comments?

 

[Keith]

The soot on those 'plug' bricks looking up from street level is pretty minor. Very likely every new owner since 1860 has tried a small fire at street level and run out into street coughing, as I did. Though in 2026, five smoke detectors and two CO detectors added to the its crowd-drawing excitement.

Photo now is of the 1860s first floor (British English) cast iron range. Exactly what is behind and below is currently mysterious but there is rubble, likely the top of the plug. Presumably dismembering the range is a no-no for grade 2 listed house.

 

[Kearn]

The soot on those 'plug' bricks looking up from street level is pretty minor. Very likely every new owner since 1860 has tried a small fire at street level and run out into street coughing, as I did. Though in 2026, five smoke detectors and two CO detectors added to the its crowd-drawing excitement.

Photo now is of the 1860s first floor (British English) cast iron range. Exactly what is behind and below is currently mysterious but there is rubble, likely the top of the plug. Presumably dismembering the range is a no-nView attachment 19264o for grade 2 listed house.

The infill bricks have noticeably sooted single faces - stretcher/header, implying they received this build up while part of the built structure, likely a fireback/cheeks or not far above. Might be that there was no opening above and they were removed to insert the range.
This isn’t incidental sooting from the odd fire below.

 

[Cubist]

I think I would want to know what, if any, of the stoves weight was being carried by that plug and whether, if the plug was dislodged, any of the remaining support under the stove may be compromised. My temptation would be to get the stove out of the way first. Dismantling those things to reduce weight and reveal any fixings is reasonably straightforward and the biggest challenges are rusted/heat damaged nuts and bolts and the final carcass weight.

As for shifting the plug itself I would be tempted to improvise/construct a simple debris chute to slow that rubble before it can hit the ground after prodding it with a stick. That aside, you may find that said prodding further jams the debris and forces you to attack it from above.

BTW - That stove is a lovely example and appears to be complete. One concern though would be if the water cistern were plumbed in?

 

[Kearn]

Believed to be same flue, though eg Gemini AI claims that a wide enough 1640s flue might end up divided into two in the 1860s. Once I and the neighbours have renewed our life insurance policies, I might pick up the angle grinder and find out. Comments?

I’d pull away from AI a bit…!

The blocked flue looks relatively small in cross section for a 17c date, ballpark 9x15” ( brick by brick and a half based on the infill). That said, the fireplace itself is quite shallow. And the fireback is hardly sooted at all, implying not much use. I’d be thinking this is a later brick structure. Why 1640?

I’d do some measuring…up and down to understand the relationships in plan.
if there were intended to be multiple flues in the stack, or the later one above was inserted and feathered into the existing, then the lower flue would be set back behind the flue for the fireplace above. But below that, the full aperture of fireplace would be visible.

Maybe get hold of an endoscope and do some investigating through the exit points of the range/around its edges…

Another clue, not that I’m suggesting it, is intentional upper fireplaces would have corbelled brick or timber supports perpendicular to the joists, for the hearth. However, you’ve a fairly decent chunk of oak in the way, probably picking up the slack.

If they have cut into the existing single flue from the lower fire to insert the range above, then you don’t have much chance of reinstating the lower fire without reversing the insertion.

If the was space for a SS liner behind the range, you could have a burner, or open fire with a hood to gather. But you’ll only know that by brick removal…

I would be surprised if the range purely was sited on a pile of bricks chucked in the hole, but…

 

[Keith]

Curreb

I think I would want to know what, if any, of the stoves weight was being carried by that plug and whether, if the plug was dislodged, any of the remaining support under the stove may be compromised. My temptation would be to get the stove out of the way first. Dismantling those things to reduce weight and reveal any fixings is reasonably straightforward and the biggest challenges are rusted/heat damaged nuts and bolts and the final carcass weight.

As for shifting the plug itself I would be tempted to improvise/construct a simple debris chute to slow that rubble before it can hit the ground after prodding it with a stick. That aside, you may find that said prodding further jams the debris and forces you to attack it from above.

BTW - That stove is a lovely example and appears to be complete. One concern though would be if the water cistern were plumbed in?

Currently it's tough to guess how much of the weight of the stove is supported by the chaotic brick plug. Amazingly, Gemini AI predicted that owners since about 1920 would have removed baffles and much of the exhaust diversion channels from the stove, to improve outflow of exhaust from cosmetic fires since then. Indeed smoke goes straight up from the stove, so it's not totally complete. Still, 1860 isn't exciting in that location. I might take your advice in a few weeks and dismantle the stove, though indeed the big bolts aren't responding quickly to WD40.

 

[Kearn]

Curreb


Currently it's tough to guess how much of the weight of the stove is supported by the chaotic brick plug. Amazingly, Gemini AI predicted that owners since about 1920 would have removed baffles and much of the exhaust diversion channels from the stove, to improve outflow of exhaust from cosmetic fires since then. Indeed smoke goes straight up from the stove, so it's not totally complete. Still, 1860 isn't exciting in that location. I might take your advice in a few weeks and dismantle the stove, though indeed the big bolts aren't responding quickly to WD40.

I didn’t suggest dismantling the stove, far from it.

There’s far too little info on the dimensions, locations and surrounding structural interactions at this point.

What happens in the gap between the timber and the brick fireplace when you look up?

Where does the front of the stove sit in relation?

What does the opening look like from a wider angle from below?

 

[Keith]

Kearn, my reply about possible stove dismantling was intended for cubist. Certainly we are trying to make best guesses with very incomplete information. Getting more measurements could involve provoking both the poised chaotic brick plug and the grade 2 listing enforcement folk. I'll aim to post a photo of the possibly 1860s fluting between street level and the first floor. The chaotic brick plug is indeed about a quarter the area of the chimney width immediately above the ground floor fireplace.

 

[Kearn]

Kearn, my reply about possible stove dismantling was intended for cubist. Certainly we are trying to make best guesses with very incomplete information. Getting more measurements could involve provoking both the poised chaotic brick plug and the grade 2 listing enforcement folk. I'll aim to post a photo of the possibly 1860s fluting between street level and the first floor. The chaotic brick plug is indeed about a quarter the area of the chimney width immediately above the ground floor fireplace.

Yep, spotted that!

None of the measurements I have mentioned would involved poking any thing or anyone… well, maybe a few discrete holes at the sides of the stove for an endoscope to pop through… but taking a step back and understanding the wider picture, quite literally and how things relate to each other in their locations.

 

[Cubist]

I'm wondering if there any clues to be had by looking underneath that carpet, particularly the section tucked beneath the stoves firebox? I am guessing that a hearth may project out into the room but if there is not and the rest of that floor is a suspended wooden plank structure its proximity to the firebox may confirm a suspicion I have that the stove has never been used in anger.

As per @kearns thoughts, it's important/wise to understand the structural elements and further investigation around the stove should be top of the list. With that in mind, and before shifting the stove itself, I'm wondering how easy it might be to remove that surround? It could easily be hiding much of the data needed and/or provide access for closer visual investigation.

 

[Keith]

Thanks for suggestions. Here's a few more photos from ground floor:



That above inglenook - warm from fire in frigid 1640s room - is 60 cm deep and fits a slim adult.


The above shows the main fireplace about ine metre above ground floor level, where it's 95cm wide.



And about 2.2 metres above ground floor level, width is reduced to about 35cm. Measurements a little hasty in view of the maybe 50 bricks poised above about 1.5 metres above my head. Till Venturi wrote his stuff in 1797 and people read it by 1840, it was assumed that wide chimney was a good chimney, no surprise, but apparently then narrowing/fluting of chimneys became the tech sensation. So my understanding is that the bricks doing the narrowing were probably added about then, maybe with idea of having fires lit at ground and first floor levels? Makes sense or...?

 

[Keith]

Yep, spotted that!

None of the measurements I have mentioned would involved poking any thing or anyone… well, maybe a few discrete holes at the sides of the stove for an endoscope to pop through… but taking a step back and understanding the wider picture, quite literally and how things relate to each other in their locations.

Yes, actually I've done some poking around with an endoscope and a few preliminary attempts at making nondestructive measurements, starting with what is above what. I'll try more when I'm back in Lincoln in a week or three, but meanwhile my daughter wants to get her career going and not hear the word 'inglenook' for a while.

 

[Kearn]

What does the external stack look like?

The plan view of all of this is key… looks likely that the rear of the chimney slopes away, as you’d expect and could indeed allow space for a shallow depth 1st floor fireplace to sit above, with its own flue running in front of this one.

What doesn’t sit right, is the lack of soot - this doesn’t look like an open fireplace which has been used in anger. The fireback at the base is intact, you would expect to see destroyed bricks here. I wonder if there was also a range or a tall hob grate in this one too.