Sandstone fireplace painting

[stationmaster]

Hi, we have a 1901 fireplace that had a back boiler fire for water heating, I ripped it all out, and after a lot of work have got back to the stone. The mortar was crumbling and I have replaced most of it in prep for a woodburner installation.
I need to seal the wall and paint it black, I have experimented with a black heat resistant spray, which bonds fairly well, but should I seal it all first, and if so, with what. We have a low budget so looking for most cost effective route.¹

 

[a twig]

Why do you need to seal and paint it?

 

[stationmaster]

Ultimately we don't, but we would prefer a black back drop, so it's a style choice

 

[a twig]

Fair enough, if it were me I’d just slap this in the colour of your choice straight onto the stonework, no sealing needed:

Graphenstone GrafClean Colour | VOC-Free Multi-Surface Matt Paint

Buy Graphenstone GrafClean White at Rawlins Paints, ecoGreen paint suitable for both interior and exterior walls, free of all toxic substances and highly breathable.

www.rawlinspaints.com

 

[Kearn]

Ultimately we don't, but we would prefer a black back drop, so it's a style choice

To achieve a visual black you do not need to compromise the material by sealing. Fireplace stacks are a magnet for damp - let it breathe.

 

[stationmaster]

To achieve a visual black you do not need to compromise the material by sealing. Fireplace stacks are a magnet for damp - let it breathe.

That was my only fear, sealing it stops the stone breathing, good point

 

[stationmaster]

Fair enough, if it were me I’d just slap this in the colour of your choice straight onto the stonework, no sealing needed:

Graphenstone GrafClean Colour | VOC-Free Multi-Surface Matt Paint

Buy Graphenstone GrafClean White at Rawlins Paints, ecoGreen paint suitable for both interior and exterior walls, free of all toxic substances and highly breathable.

www.rawlinspaints.com

Was looking at rawlins, so thanks, all lime plaster walls done in graphenstone, looks great, but expensive shipping it to the Highlands, good advice thanks

 

[paulc]

Ultimately we don't, but we would prefer a black back drop, so it's a style choice

Do you want to retain the texture of the stone or happy with a smooth finish ?
A quick & dirty way of getting a smooth finish is to fix some cement boards to the sides & back and then slap some paint on. However, a stove will radiate quite a bit of heat, and you may find some paints bubble and discolour. An alternative would be to mix a load of carbon black pigment in to a bucket of lime plaster and apply it to the walls. I've done something very similar with my stove, but I went of a shiny polished finish.
To retain the texture of the stone, a lime wash loaded up with carbon black would work. You won't get a true black, but it will be breathable.

 

[housewinnie]

Why not leave it as in and find an old cast fireback by the time the stove is in you will not see much