Widening Chimney Opening

Joined
22 Nov 2024
Messages
3
Reaction score
0
Country
United Kingdom
Hello, I am pretty far along in my house reno - many thanks to all the posters here! We would like to put in a log burner, this opening is where the gas fireplace/backboiler used to be.

As shown, its rather small. It is currently 590wide and 570 tall. I think a good size would be 900 x 900.

My lintel is rather high, and not very wide so I imagine this needs replacing, or another inserted below? (considering I don't need the opening that tall). It also has a crack in the middle, but it doesn't look very wide / deep and I imagine this is OK as well as it has no where to move? At least thats what my structural eng said about the lintels above my door :LOL:

There is plenty of info and videos on how to add / change a lintel - I just find it hard to understand the makeup of a chimney and am hoping some here can advise, I have posted a photo of the chimney and the inside looking up.

I am a bit confused by the ^ shape brickwork. it starts just at the vertical opening, where there is a steel plate. I assume this is ONLY holding up all the brickwork under the lintel?

I can't see that there is anything above them. when increasing the height of the opening is it safe to remove these?
This is a semi detached. So this will back onto the same chimney as the neighbour, there are 2 pots on the roof. In the bedroom above here the brickwork is a lot skinnier.

1. Whats the best approach to widen and tallen this opening? Replace lintel with longer one and do a similar metal plate to get the desired height or insert another lintel at the desired height?

2. Can I remove the ^ safely or does it need some other structure instead?

3. I'm not against hiring somone, rough cost? (I am pretty competent DIY so it couldn't be silly money)

Many thanks!


CHimney.JPG
chimney_inside.png
 
Sponsored Links
Old steel flue from a wood burner up inside chimney?
Just install a new concrete lintel.
Cut the hole bigger and cement in. Probably lime mortar.
Cut opening bigger and nothings will happen.
Will all hold together
 
Old steel flue from a wood burner up inside chimney?
Just install a new concrete lintel.
Cut the hole bigger and cement in. Probably lime mortar.
Cut opening bigger and nothings will happen.
Will all hold together

Thanks for you advice.

Its the old duct for the gas boiler/fireplace that was there.

Just to be clear, do you mean remove the current lintel, cut the sides bigger, and install the new lintel? I wouldn't need to put in some strongboys or anything?

Cheers
 
OP,
You must install the burner to Mfr's installation dimensions - so you first need to select a burner.
Why not use the search button to find member: ree - search: opening up a fireplace?
There you will find a number of my recent posts on how to do what you propose.

For now, leave alone the SS flex flue liner that was used with the old gas fire.
Dont remove any brickwork until you have the Mfr's dimensions.
Then come back & I'll help you to safely install a lintel.
The gas pipe and gas restrictor valve, & any elec cables or devices must be removed by qualified people.
The flow & return pipes from the old boiler must also be removed back to any cylinder.
Might be best to remove all the board & batten as well.
 
Sponsored Links
OP,
You must install the burner to Mfr's installation dimensions - so you first need to select a burner.
Why not use the search button to find member: ree - search: opening up a fireplace?
There you will find a number of my recent posts on how to do what you propose.

For now, leave alone the SS flex flue liner that was used with the old gas fire.
Thanks for your reply. Yes was planning to leave the SS liner for when the HETAS people come.

Those are completely dead pipes, I should have specified. My plumber did all the work of installing a complete new heating circuit and gas pipe to the new boiler location, I appreciate you checking though!

I have a few burners that I like the look of, and all would fit well within a 900x900 opening. Far as I know you cannot have "too large" an opening so as long as I have options this should be fine.

I agree that I will likely remove all the board and batten and have it re-boarded once the fireplace below is done. I will go have a look at your post history, many thanks for your input!

I did receive a quote of £4k for the complete work. This seems steep to me, so I'm hoping if im only paying a HETAS for the flue / register plate/ connection to stove that should hopefully save me some.
 
OP,
Remove all redundant pipework esp. gas pipes & devices.
The upper lintel in your first pic could possibly be left in place, & might well do for lintelling the new opening.
The price is what it is.
HETAS will only do the full installation procedure which will(or should) involve examining the flex flue terminal on the stack, smoke testing, & evaluating the condition of the SS liner, & more.
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Back
Top