Looking for some advice for repairing a wall in my new house, in the United Kingdom.
I'm in the process of buying a house, all in great condition except for one wall in the living room. It's been behind a cabinet thing and basically the wall has crumbled and left a hole, exposing the brick behind it (bricks because its an exterior wall, but the issue is inside the house if you get me). The brick seems fine, but the wall part needs repairing obviously. I didn't get a picture of it during the viewing, and I don't have access to the property yet, but here's a similar picture I found online of what it sort of looks like.
https://imgur.com/a/NdsqJ07
Its like this but bigger (about 1.5m across the wall, from the ground up to almost 1m above the ground I think). I reckon the depth of the crumbled wall is about 2-3cm deep. I'll update the post with an actual picture when the purchase is complete.
How do I get around to repairing this? I'd like to do it myself, rather than pay someone to do it, I have a lot of tools, and can easily buy any materials that I need.
My current plan is just to dust away any debris, and then apply a wall filler (eg multipurpose pre-mixed Polyfilla) in layers all over the area, letting it dry between <10mm layers. Then just sand it down flat with sandpaper, and paint over it with a paint roller and wall paint.
Is there anything wrong with my plan? Worried I might need some layer of sorts (waterproofing?) between the brick and the filler. And do I need some layer between the filler and wall paint (primer/emulsion? waterproofing again?) ?
Would appreciate any advice, I'm still relatively new to DIY (and reddit). If there's a better subreddit to post this to, please let me know! Thanks!