Patching plaster decorating

[bobkins]

Hello, we've had our 1930's house rewired and consequently have a lot of patching plaster which now needs decorating. I made a start but have had a disaster! I mist-coated the bare plaster but when I put the first finish-coat on the feathered in plaster came off on my roller. I've scraped away the loose stuff but not sure how to proceed. I wondered if I could coat the bare plaster with Zinnser Gardz with generous margins? Not sure at what point to try and fill the damaged areas (planning to use Toupret) These patches are throughout the house so I want to get it right next time. The other complication is that the previous house owner has used silk paint throughout (including ceilings) and in some rooms doesn't seem to have done a mist cost so I've been able to peel the paint off the walls. Feeling completely overwhelmed so any advice would very much be appreciated.

 

[Wayners]

Old chalky emulsion that's degraded so plaster never stuck where plaster was feathered out?

 

[bobkins]

Hello, thanks for your reply...the patching in has been feathered out over silk emulsion.

 

[Wayners]

Ah. Silk needed sanding to create a key for filler

 

[bobkins]

The plasterer just went ahead and did everything after the rewire...I don't know if he sanded or not. I'm just trying to work out a plan of action as the whole house has been rewired/switches and sockets moved

 

[Wayners]

Get some toupret powder and make good.Will stick better.
Sand. Stick 120 grade to something flat like a block of wood.