Patching chimney breast

[Scarrison]

Total amateur here. I'm having a 5kw woodburner installed in our lounge later in the year. We took out an old open fire and opened the original 30s chimney breast.

I want to have a go at tidying up the chimney breast myself, but keep seeing conflicting information about plaster types/methods when looking on here and youtube videos.

My original plan was to cover the brickwork with SBR & cement slurry, then two coats of sand & cement render (scratched of course) . My neighbour who is a handyman said to skim with multi finish on top of that, but from doing research I'm now worried about heat resistance.

I'm planning on pointing and painting the brickwork in the chamber.

Also just thinking about the corners and uneven brickwork, would corner bead be OK on the chimney breast and stop bead around the chamber? What's the best way to make up the gaps? I'm aware I need to straighten out the lintel, gonna have a go with the grinder..

(excuse all the materials in the way in the photo, that's where I'm storing them for now)

Any advice Much appreciated, thanks guys!

 

[smoother09]

Looks awesome I’m sure between you and handy Andy next door you will have it looking bonza!! Tile it looks dapper

 

[Steve Brown]

Looks awesome I’m sure between you and handy Andy next door you will have it looking bonza!! Tile it looks dapper

Hi there I had a similar case like you, remove any loose blown plaster, PVA, dab a board to the whole front of the fireplace wall bead up then skim.
I cut back the edges and trimmed the bead to fit so you could see the brickwork. Here’s some photos hope this helps

 

[Chris W]

wouldnt bother covering the entire house in dust with a grinder...
fix a render stop bead to the lintel... drill it 6mm, use red plugs and bang a 40mm galvanised nail in, chip a key into the concrete
heat isnt gonna be a problem, its on the face
fix a render corner bead to the corners same way keeping it straight and inline with the existing finish at the top..
stop bead the edge of the aperture, leave em 2mm proud of existing finish...
gob any big gaps out with sand and cement... let it go off for a day to stop it cracking due to thickness
render it in one coat using waterproofing additive (3 in one stuff) 2mm shy at the aperture
stick thincoat corner beads all the way to the top at the external corners...
skim it couple of days later making sure you kill the suction enough on the existing plaster
point up a bit behind stop bead in aperture
tricky bit really is using the render beads to trowel the finish up to so youll need to float the render a bit shy round the aperture and make sure the beads are a couple of mill proud of the existing finish
dunno how flat the rest of the breast is so guage youre bead positions based on that and use a bit of bonding if you have to

 

[jamesthefirst]

You make it sound so easy Chris W.

 

[Tony rover]

My advice around an open fire or log burner would be to reinstate and point the brick work or tile. The heat over time will eventually get at the plaster. Never dot & dab around a fire place, against fire regulations.

 

[Scarrison]

Thanks for your advice everyone, it's given me something to think about.

@Chris W - thanks so much for your detailed reply. Just a couple questions if I may..

With the lintel, are you suggesting I restore the profile with cement? The chunks missing are 40mm deep in spots so I'd worry it wouldn't hold? The woodburner guy needs to fit the plate to it I think. I've attached a better pic

The rest of the breast above the opening is pretty flat and the plaster seems mostly fine.

Can I put plaster bead on top of render bead, in the case of the outside corners?

Thanks again.

 

[Chris W]

Render beads only to get your corner straight when you render it, theyll only be 2 or 3 foot, hieght of the exposed brick. Once its rendered you can stick full height plaster beads over the lot and that will give you a nice corner when its skimmed... Skim the cheeks (sides) too...
You could wedge a bit of timber tight up under the lintel and gob it up a bit before you fix a stop bead to the face, drill a couple of proud screws underneath in the hollows to grab it and make sure it stays put, take timber out when its gone off a day or 2 later and the plate will sit nice under it..

 

[Chris W]

Tony rover seems concerned about heat on the face so if your worried make your render mix an 8:1:1 - 8 plastering sand, 1 lime, 1 cement... Should give it a tad more flexibility

 

[Chris W]

It is to me, and you, and any half decent spread... I even make it look easy when im working...
Its only when people have a go themselves thinking it IS easy because it LOOKS easy they realise thats what you pay a plasterer for but end of the day if he cocks it up he can hack it off and have another bash

 

[Tony rover]

Tony rover seems concerned about heat on the face so if your worried make your render mix an 8:1:1 - 8 plastering sand, 1 lime, 1 cement... Should give it a tad more flexibility

Just the nature of a log burner/open fire. The most flexible render I know of is silicone, wouldn’t look right around a fireplace imo. End of the day the heat will f**k up solid plaster.

 

[John j]

Just the nature of a log burner/open fire. The most flexible render I know of is silicone, wouldn’t look right around a fireplace imo. End of the day the heat will f**k up solid plaster.

Buy one of them I got where you put water in and it looks like burner . Ha a little electric heater underneath . Which you will use twice a year
And then you wont have to clean it out and have a wood yard in your garden and work bout wrong type of plaster

 

[Tony rover]

Buy one of them I got where you put water in and it looks like burner . Ha a little electric heater underneath . Which you will use twice a year
And then you wont have to clean it out and have a wood yard in your garden and work bout wrong type of plaster

I love an open flame. When I plaster something I am always thinking ahead, life span, I want want it to last. If the surround is brick then it’s less messing about in my book.