Widening Fireplace to have more room around log burner

[Whitefusion]

Hello we have just bought a house, and we would like to open our fireplace to have more space around the log burner, I took out the fire this weekend and hacked off some of the plaster around with a SDS drill, we want to open up by about 6 inches each side, but im concerned it will be to wide for the chimney breast. Please see the picture below and if somebody can advise what I should do that would be amazing.

My concern is that if I hit the bricks down on each side this will go through the chimney breast, or at least the first skin. 

[Marvin]

The lintle above the existing fireplace opening looks not wide enough to take the new opening size.

Is that a solid external wall?

Edited November 1, 2021 by Marvin

[epsilonGreedy]

A reinforced concrete lintel 140mm high by 100mm wide will hold up the internal wall of the chimney breast across your desired 1.1m increased width. I cannot comment on the structural surgery required to transition to the new opening, my house was only 5ft High when I decided to demolish the chimney and widen it.

 

Given the effort involved why stop at 1.1m? How wide is the room along the wall photoed?

[ProDave]

Widening that opening would leave too little bearing for the lintel.

 

Can your stove do a rear exit flue?  If so I would just use that which would make the stove sit out into the room a bit more.

[Whitefusion]

11 minutes ago, Marvin said:

The lintle above the existing fireplace opening looks not wide enough to take the new opening size.

Is that a solid external wall?

Im happy to put a new lintel in that is wider if need be, and yes this is an solid external wall .

[Marvin]

10 minutes ago, Whitefusion said:

Im happy to put a new lintel in that is wider if need be, and yes this is an solid external wall .

Well it appears, judging by your photos and measurements the you would end up with the following: 

Both of which are no good. So need to sort out design.

 

M

[Whitefusion]

8 minutes ago, epsilonGreedy said:

A reinforced concrete lintel 140mm high by 100mm wide will hold up the internal wall of the chimney breast across your desired 1.1m increased width. I cannot comment on the structural surgery required to transition to the new opening, my house was only 5ft High when I decided to demolish the chimney and widen it.

 

Given the effort involved why stop at 1.1m? How wide is the room along the wall photoed?

 

Im happy to fit a wider lintel, what i'm concerned about is the width of fire being close to the width of the external chimney size and with the look of the bricks it could be and issue if I cut through them

[Whitefusion]

3 minutes ago, Marvin said:

Well it appears, judging by your photos and measurements the you would end up with the following: 

Both of which are no good. So need to sort out design.

 

M

Depth is fine only need the width to be wider

[Marvin]

More detail for you look at the sizes...

[Marvin]

How deep is the fireplace into the wall? My guess is about 330mm...

 

[Whitefusion]

The depth is fine we are ok with that on how deep it is, as we plan on building a bit of a chimney breast in the front so we can flush mount a TV the only thing we need to do widen the chimney, as there is not much space on each end.

The only other way I can think would be to pull the log burner forward and then board over the chiney and have the Log burner in front with the pipe exiting the back of the log burner and upto the chimney breast 

[Marvin]

6 minutes ago, Whitefusion said:

The depth is fine we are ok with that on how deep it is, as we plan on building a bit of a chimney breast in the front so we can flush mount a TV the only thing we need to do widen the chimney, as there is not much space on each end.

The only other way I can think would be to pull the log burner forward and then board over the chiney and have the Log burner in front with the pipe exiting the back of the log burner and upto the chimney breast 

Sorry for the confusion. I was not saying to go deeper. If you widen the hole on both sides you will cut into the bricks that hold up the existing lintle. If you cut the width wider all the way to the back of the existing fireplace you will be cutting into the sidewalls of the chimney stack outside.

 

Nice idea to extend the the log burner into the room instead. Don't forget the non flammable hearth requirements and the non flammable boarding anywhere near the flue.

[epsilonGreedy]

It would be useful to see a photo of an example fireplace that you want to implement. Are you keeping the current stove? Do you want a feature brick lining of the new fireplace?

 

Having spent many hours thinking about fireplace design I suggest that if you extend the fireplace inwards then incorporate wide cheeks in the design. One brick wide cheeks (100mm) look naff.

 

Re. Depth I think a stove that projects 50mm forward of the chimney breast looks about right.

[markc]

1350 outside is never going to give you 1100 inside.

[Whitefusion]

SO basically I want it to look something like this

See images but with a log burner with the TV mounted above it

[Whitefusion]

37 minutes ago, epsilonGreedy said:

It would be useful to see a photo of an example fireplace that you want to implement. Are you keeping the current stove? Do you want a feature brick lining of the new fireplace?

 

Having spent many hours thinking about fireplace design I suggest that if you extend the fireplace inwards then incorporate wide cheeks in the design. One brick wide cheeks (100mm) look naff.

 

Re. Depth I think a stove that projects 50mm forward of the chimney breast looks about right.

 

Do you have an example pic of what you mean

[joe90]

54 minutes ago, markc said:

1350 outside is never going to give you 1100 inside.

It will but will give you only 125mm thick brickwork per side of the external flue walls, you will need to then corbel the brickwork on each side to support the sides above ?

[dpmiller]

won't the telly get a bit toasty?

[Whitefusion]

Would this work what do you all think so not playing with the fireplace to much and building out around it . (If I go this route do I need to think about anything else ?)

Edited November 1, 2021 by Whitefusion
Add more info

[ETC]

If you widen the opening you will more than likely be affecting the cavity wall that I presume encloses the fireplace. The only options you have are:

• Put in a smaller stove and leave the opening as it is.
• Build a separate chimney breast inside the room as suggested by @Whitefusion above. Might be wee bit tricky to connect the flue to the existing chimney. Consider construction materials in relation to heat from the stove - your stove supplier will be able to advise you on distances of the stove and flue from combustible materials.

[Roundtuit]

1 hour ago, dpmiller said:

won't the telly get a bit toasty?

And be too high?  I know it's a bit of a thing to put the TV on the chimney breast, but it can be too high for optimal viewing comfort.

[Marvin]

1 hour ago, dpmiller said:

won't the telly get a bit toasty?

Yes they dry out and stop working. .

[ProDave]

21 minutes ago, Roundtuit said:

And be too high?  I know it's a bit of a thing to put the TV on the chimney breast, but it can be too high for optimal viewing comfort.

Yes that is definitely my opinion.

 

I set my tv low on the wall, but at what I regard a comfortable height

 

[Marvin]

Thoughts that may help:

 

Was the original burner installed by a HETAS engineer?  Was the stove used or just for display?

 

Is the chimney lined?

 

Is the room deep enough to have the 300mm deep hearth extending into the room in front of the proposed extended stove position?

 

HETAS engineer required?

 

Carbon monoxide Alarm required.

 

Technically building regulations required.

 

Air brick required?

 

Marvin

 

[epsilonGreedy]

6 hours ago, Whitefusion said:

 

Do you have an example pic of what you mean

 

 

The 2nd and 3rd photos you uploaded are examples of well proportioned leg widths, they appear to be 250mm to 400mm wide. I called them cheeks in my post earlier but after looking at a diagram I understand the fireplace cheeks are not present in a purpose designed stove fireplace.

 

Your later fireplace design that wraps the existing fireplace in a grander chimney breast make more sense and creates what you want for much less disruption.