Opening a Fireplace

13 Feb 2011
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United Kingdom
Hi All,

I have a late Victorian terrace property, circa 1900. I want to open up the chimney breast in the front room with a view to installing a wood burner.

I've got as far as removing the plaster to expose the bricked up fireplace - photo below:

The double brick arch looks to be the top of the old opening - the couple of bricks I removed had soot on the bottom and back.

My question is how I should support the wall above the opening. The arches don't appear to be supporting the wall above, as they're loose as are the bricks I've exposed directly above them. I was able to remove the bricks I did with little effort.

I'm thinking that maybe I should prop the wall in the opening I've make with and acro/strongboy, then remove the loose arches and replace with a concrete lintel before removing the brickwork below.

However I'm also wondering if there might be another lintel above the arch that is providing the structural support - hence the loose bricks in the arches. I'll take some more plaster off tomorrow to have a look.

Any advice or experience on how to proceed would be appreciated.



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Hi Andy

How will your finished article look?

We did something similar in our last house, but luckily none of the arch bricks dropped down, we opened up the fireplace which had bricks to the sides and rear - It was just a matter of us wire brushing the bricks by hand and with a drill disc to clean them up a bit and re-pointing.

We then plastered back up and placed a wooden surround against the wall.

It looked like this when we were opening up the gap.

Once we had the opening done we checked with the surround to see what the sizes were and how much plaster had to come off etc.

I then started pointing up and added a bit of cement to a patch on the floor.

Unfortunately you cant see the full picture but it gives you an idea of how it looked when finished.

I think if it was me I would carefully take out the plaster for the area needed, I would then see how loose the bricks are (I might even be tempted to try and point some up to see if it strengthened them up a bit)

Back then they used lime in the mix didn't they?
I was able to scrape / rake out the joints between the bricks before I pointed up - so a cement mix should add some strength if re-pointed.

I would then carefully try and take out the bricks downwards from the middle and if needed get a support or acro in there.

You can go for a lintel if needed or you can also purchase an arched (bent) steel bar that should fit directly under the archway of bricks (bricks done that way are called soldiers I think)
An arched steel lintel should fit in between the joints of the bricks on either side and would have cement pointed in between that and the bricks.

Expect a lot of mess and soot and crap, Those fireplaces have a lot of stuff to the rear - we got bags of like dust/sand and stuff from under the concrete hearth.

You can always check out this post from our current Fireplace, we are having a mantel made up to go above the fire at present.


I would say if your fire is under the fireplace and you have a pipe through the top of the stove then the bricks either side get very warm, if you have a pipe from the back of a stove and your fire is further forward then any surround would absorb some heat - Our previous surround was fine but it was always a worry in case any finish on the surround might melt with the heat (luckily it didn't)

Another thing to look at with a stove (if that's what your having)
Some stoves allow you to take out what I think they call the throat plate, this allows chimney rods straight up for easy cleaning (our last Arrow stove allowed this) Others don't always give that luxury so you might want to look at a pipe with a door built in or even putting a soot box into the chimney stack above.

Just my thoughts on things but I am no expert - hopefully some bits might be of use.

Let us know how you get on and post a few pics along the way.
Hi Always Learning,

Thanks for your reply - very detailed. I'm looking for something not dissimilar to what you've got in your new place - a square rendered opening without a surround, possibly a mantel. However, looking at the fun you had with fireproof plaster, I might opt to keep the bricks inside the opening exposed!

Either way, I think I need to check the state of the brickwork further up above the arch. If that's in good nick, I'll be more confident in rebuilding/repointing the arch. If it's looking loose, I think I'll need to look at propping it and putting a lintel in.

I'll take some more plaster off and post some more photos.


Andy I wish our brickwork was really good as I prefer that look, unfortunately some areas were a mess - looking back I made some mistakes.

The fireproof boards were cut down so they would fit in the car because the weather was that bad that they would not deliver, although I used 2 coats of heat resistant plaster we ended up getting some cracks where the boards joined, I should have used some scrim over the joins but I didn't.

Other then that the plaster everywhere else has held up really well, we are having a mantel made up from an old railway sleeper - My father in law has planed it back & it's looking really good, hopefully we should have it fixed up within the next 2 weeks, I will post a pick when it's done.

I am really happy with the log burner, if we put our heating on full blast we are still cold as some of the radiators are singles, but the log burner on it's own gives enough heat and also the landing upstairs gets warm.

Just try to get seasoned wood, we buy 4 ton of pine and cut and split it but it needs to be left to dry out - The drier the wood the more heat you get but also the quicker it seems to burn.

Good luck mate - keep us posted on your progress.
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Right, I've been busy with the chisel again, and I've taken some more plaster off. It's now clear from the photo below that there is no other lintel above the arch:

It's also clear that the arch has slipped at some point and and is no longer supporting anything. The new hole on the left had a few bits of loose brick in it - it goes to the void between the internal flue wall and the outer chimney breast wall.

So the question becomes how to put a lintel in to replace the arch. I'm thinking that I can remove the top loose brick above the arch and insert a acro/strongboy to support the wall in the centre:

Then remove the loose bricks in the arch below and in a row to each side along the level of the highest missing brick, and insert a lintel along that line as in this squashed image:

Do you think i'd be better off propping it differently? Also I'm not sure if that will be too far up the chimney breast, but I should be able to rebuild an arch below the lintel with the aid of a former if necessary.

Any thoughts or advice?


Hi Andy

I have no experience at inserting lintels or using acro/strongboy's but I have seen different types of lintel when visiting a builders yard.

There is the metal/steel type and the concrete ones, looking at your picture I am unsure if you would be taking out more then you have too - would that line for the lintel be too long?

If you shine a torch through the holes where you removed the bricks can you see the sides of the previous fireplace walls? If so and the width is fine then would you not just need a lintel to cover the width of the fireplace and maybe 2 bricks wider either side.

(I am just guessing here as I have no experience, the 2 fireplaces I did were straight forward - I didn't have the loose archway and bricks that you have)

Hopefully someone in the know on here will pass over some valuable knowledge on this matter - sometimes people post/answer a lot and other times threads move down the pecking order and get missed it seems.

One idea could be to phone a local builder (who you can trust) and get them to talk you through the process, you could ask for a quote and ask how they would go about the job, pick their brain and if the job seems doable then take it on.

We just had a mantel made which we fitted today, luckily a family member made it free from an old sleeper so we got a bargain.

Keep us posted as I am always interested - problems like this are worth knowing about in case we ever move again and run into the same situation.

I just found this on a google search which looks like it could help you (I hope)
Hi All,

A little update on the weekend's work. With some help from a bricklayer friend, we've got the lintel in, and the arch rebuilt using the bricks below as a former - this seemed easier than opening up the fireplace straight away and then having to make a wooden former to build the arch back later.

The props are still in as the mortar around the brickwork above is pretty poor quality, and will need re-pointing. We decided it would be better to let the new mortar around the lintel set before we put the load onto it. The green line below the arch is plastic to stop the mortar in the new arch bonding to the brickwork below which still needs to be removed.

I've also found a picture of what I hope the finished article will look like - this will help greatly when i'm trying to explain to the plasterer what I want!

I'll post again once I've opened the fireplace up properly.


nice work andy, well done!
andy can you tell me how you fitted that prop in, did you use a length of wood inbetween the props to hold the breast up?
Hi Diy001,

The acro has a strongboy attachment on top. Basically it's a cantilever that fits on top of the acro and sticks out at 90 degrees, allowing you to support things that you can't get directly underneath.

Just ask for a strongboy from your hire place and then should have them.


morning andy. thanks for the info. if you have any better pics of the acro + the attachment would be great to have a look.

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