Fireplace Renovations

[HH @ 24]

I am renovating a cottage and have stripped back the two fireplaces which were covered in concrete render, plaster and new brick.

I've spent many months chipping away on the inglenook with various chisels and hand tools and have got about as far as I can. But it all needs a good clean and some way to remove the final stubborn bits of concrete, before it's all repointed in lime (right hand cheek will be re-built in old brick). I've tried using a wire quick strip disc on my drill but that isn't doing much. I thought about hiring a needle scaler/gun but have read this wouldn't be particularly effective and will make a mess of the face of the brick/stone. My other option is to use diluted hydrochloric acid and spray it on, something like this https://www.jennychem.com/products/...scJM3qnT5QBEjao_E_0MlO2V7m98SkiYaAp7xEALw_wcB
diluted down more.
I have tried Biostrip Concrete Remover https://www.amazon.co.uk/Biostrip-Concrete-Remover-concrete-cleaner/dp/B01619EP1I/ref=sr_1_fkmr0_1?crid=18WHPXRBQY7F&keywords=brick+cleaner+fuzz&qid=1689939423&sprefix=brick+cleaner+fuzz,aps,65&sr=8-1-fkmr0 ;
it didn't make one iota of difference, but assume hydrochloric acid will be stronger.

No idea what is on the sandstone lintel on the other fireplace; it looks like some kind of solidified adhesive. This is going to have a support put in above the lintel, the bricks below removed and re-plastered around, just leaving the lintel exposed...if it looks okay once I've removed the dark covering. It's very worn, as you can see...but it is old! Don't want to replace it unless I really have to.

Any advice greatly appreciated.

Thanks

 

[88v8]

The smaller fireplace, I wonder if the lintel was ever meant to be visible, I would think that there would have been a surround, but given that the surround if any is lost ... so, you're planning to plaster so it just overlaps the top and ends of the lintel?

If you can prop it in the middle and remove the lower bricks you may be able to get behind and attach a long steel plate behind with masonry bolts - go gently! or it could shatter - and then it won't fall down. Otherwise, a support above won't stop it falling under its own weight.

Removing old glue can be difficult. If a heat gun doesn't help then hmm.

I see the lintel is also cracked at the rh end, it ain't gonna look great after all your hard work....
You can age new sandstone by rubbing it with soot. Just saying..... And if you were to insert a new lintel you could set it forward slightly and then plaster up to the edge of it.

The inglenook, caramba that's a patchwork with a tale to tell.

As you say, needle scabblers are hard going and will chew up the face of soft reds.
If some of the dross is cement it will be harder than the brick so difficult to blast it off with soda or the like.

I would go to your local builders' merchants and get some acid brick cleaner, and brush it on, not spray, work on a small area. Brick acid will destroy the lime mortar, but I imagine you are gong to rake it out and repoint in lime anyway.

Focus on a brick at a time, then you will be able to see your progress. I do not think it will be possible to get it completely clean, but you could expect a significant improvement, and when it is all repointed it will look a whole lot better anyway.

 

[HH @ 24]

Thank you, that's all great advice.

Smaller fireplace; yes I was planning to plaster so it just overlaps the top and ends of the lintel. I think I may replace the lintel; I can source a reclaimed one, so it will still have some character. Chipping away at the glue is just making a mess of the face of the sandstone....and taking forever. And with all the cracks in it, it's never going to look great. Setting the new slightly one forward is a great idea.

Inglenook, yes I agree, I think acid is the only way forward. Yes I'm going to re-point it all in lime, so it doesn't matter about the acid destroying the existing lime. Why do you say brush the acid rather than spray? I'm not expecting it to ever look perfect, but if I can improve a little on what's there; once it's re-pointed and the fire is in situ, hopefully it should all come together!

 

[88v8]

Why do you say brush the acid rather than spray? I'm not expecting it to ever look perfect, but if I can improve a little on what's there; once it's re-pointed and the fire is in situ, hopefully it should all come together!

Because brick cleaner is very aggressive and that way you can control it.
Bizarrely, you want to damp the wall before applying the acid, that way it will sit on the cement rather than soaking into the soft bricks.

The newer the mortar the better it is likely to work.

Goggles, acid-proof gloves and a brass-bristled brush.....

Yes, when it's pointed it will look infinitely better, even with some inevitable residue.