How to repair flaking/peeling paint when painting room?

ninjaef

Ah, Ok, yes II get it now. I. must come across dumb to an expert like you, and my finish will never be as good as yours, hence 'm not after perfection, but just to have a good go myself. It can only need redoing at worst, at best..i would be happy if at ground level it can't be seen. 😀 thankyou for helping 👌

Alter_ego

I'd use decorators caulk in a applicator gun followed by a wet finger. After getting rid of crumbly bits of course.

donemedosh

I got this off youtube some years ago & it worked when I had to repair cracks in ceiling and walls ( I have an old house) Run a stanley knife in the cracks about 3 to 5 mm deep & about 3mm wide. Use a pollyfila of your choice (screwfix no nonesense fila is what i used) to fill in the gap. Sand it down with a fine sandpaper. Then paint over with zinsser bullseye 123. then repaint.

Jeepers_Creepers

ninjaef said:

Ah, Ok, yes II get it now. I. must come across dumb to an expert like you, and my finish will never be as good as yours, hence 'm not after perfection, but just to have a good go myself. It can only need redoing at worst, at best..i would be happy if at ground level it can't be seen. 😀 thankyou for helping 👌

You are welcome, but I am not by any stretch an expert - just a long-term DIYer. That's the way I have tackled such jobs, but it ain't the only way and might not even be the best. And my finish is often pants.

ninjaef

Wow, thanks everyone. Sorry for not coming back soon. Had some home issues to deal with - not decorating though , yet

So I have a lot to go on - so more help is better thanks everyone - ranging from

1. sanding the are down to feather out the edges and then painting it , 
2. brush loose bits away and calk and then gently sand to get an even level with the good surface, that then paint.
3. brush, fill with Tetrion, sand and paint.
4. Stiff brush to move the broken plaster away, work in Gardz/Peel Stop until it's no longer sucked in, allow to fully dry, then ronseal ready mix fine surface filler, sand, paint, sand, paint until I get surface that I can roll paint over when doing the rest of the wall.

Watched three vids - english , of course - and pretty much sway along one or combinations of , the above.
So to balance cost, speed, budget, and keep realistic as to my ability and final finish, and the fact that it's quite minor and high up and isolated to about 12 inches along the top, I am going to plumb for a stiff brush away of loose plaster then straight to surface filler then sand and a few light coats of quick dry emulsion to build it up and a sponge sand over before the full roller paint job. I'll post back the images next week when I start and I may rue the decision but let's see (and possibly learn in the process - I might need to do it again but heyhooo that's all part of learning).
Would like to extend my gratitude to the following members for kindly reading my OP, responding, and offering some good advice and sharing much valued experience: @JGB1955, @Alanp, @Mistral001, @Alter_ego, @donemedosh and of course @Jeepers_Creepers who must have burn away a few finger prints on the keyboard in his detailed posts.- Thank YOU all. 

Jeepers_Creepers

Every job is different, and what you do in this case might not be as important as your next place  :-)  

Gardz is only needed if the plaster is crumbling and dusty. Peel Stop is only needed if the surrounding paint is loose and flaky.

Caulk can be made to work if it's applied with a flat filling knife using the surrounding 'good' paint as your guide, but (a) it tends to shrink and (b) it usually cannot be sanded, so the finish you achieve is the finish you end up with.

If it's all generally sound enough, just dampen the bare plaster (to prevent it sucking the moisture out of the filler) and use a filling knife to apply a layer of ready-mixed filler, ideally 'fine surface' type. Sand when dry, and apply a further layer if needed - tho' it hopefully won't be.