Painting in new plaster

[Barnboy]

I've read through all the other posts about painting after plaster on here but I'm still not confident in what the process should be and where I've gone wrong with my 1st rooms.

The plaster finish was quite shiny so we gave it a key up with some scotch brite type pads.

We painted the bathroom ceilings after about 3 weeks last year with Zinsser bulls eyee 123 primer and  Perma white. When I drilled the spotlights the edge of the paint chipped and you could pull it off in sheets back to the plaster, when the ceiling was chipped when tiling the same happened, we've now quite easily stripped the paint completely off with a glass scraper.

The non bathroom walls were sprayed with 10% watered down emulsion as per the manufacturers instructions, we haven't put anything other than this coat on the walls so far. Masking tape of all varieties, including frog tape pull the paint off the walls and I'm worried that if I put the top coats on and come to stick some 3m picture hanging strips up any pictures will end up on the floor.

I've now bought some Macpherson Eclipse emulsion to try when the next lot of plastering is done and as a base for the bathroom ceilings.

 

[Mr Punter]

Our painter likes Johnstones Trade Covaplus Vinyl Matt.  Does a mist coat with 2 parts paint 1 part water.

 

If the paint is peeling off in sheets it is not bonding to the plaster.  Maybe you need to sand the surface before you paint.

[Barnboy]

3 hours ago, Mr Punter said:

If the paint is peeling off in sheets it is not bonding to the plaster.  Maybe you need to sand the surface before you paint.

Everything was sanded with a scotch pad.

 

[Mr Punter]

Maybe try the Johnstones?  I would only use the Zinsser for problem stains.

[Barnboy]

I think that the bathrooms are down to the Zinsser primer, I've spoken to a friendly painter who said he painted a pool house manybyears ago with it but used normal emulsion as a base/mist coat,  he says that it still looks like new today. 

My main worry is the rest of the walls where only emulsion was used, I'm hoping that that is down to the, what should be good quality paint being too good for a mist coat but I'd like to try and work that out before the same problem occurs with the macpherson rather than the better stuff we used last time.

[Alan Ambrose]

Not due to dust or damp?

[Barnboy]

We wiped everything down with a damp cloth at least a day before painting.

9 hours ago, Alan Ambrose said:

Not due to dust or damp?

[Kelvin]

I wouldn’t use those 3M sticky strips to hang pictures regardless of how good the wall was. 
 

I let the plastered walls dry for at least two weeks and used a moisture meter to check. I I also rubbed the walls down then washed with a damp sponge. I used relatively cheap Velspar coverall paint designed for fresh plaster. Doesn’t need watered down. I did two coats of this leaving at least 24 hours between the coats and then a finishing coat with a harder wearing paint appropriate for the room. All fine apart from the bottom third of one wall where the first coat was lifting off with the application of the second coat. I used Zinsser Gardz sealer primer which did the trick. 

[Beau]

I always dilute the mist coat nearer 50/50 as recommend by an experienced builder friend as the plaster takes it in better. Did our first place near 20 years ago and no peeling of the paint to date 

[Russdl]

Same as the above, our new plaster was pretty shiny, didn’t do anything to it apart from mist it 50/50 with some Wickes paint (specifically New Plaster Paint iirc?)

No issues 4 years on. 

[Barnboy]

@Kelvin what did you rub down with, paper or scotch pad and what grade  ?

so far the fresh plaster doesnt look as polished as the 1st lot so hopefully the new emsion will work watered down as the instructions say, max 40%.

I'm not sure what to do with the  Original painted walls upstairs. They would take some work to scrape off as the paint has adhered, unlike the bathroom ceilings, just not 100% stuck on. 

Do I just hit them with a drywall sander and see if that's takes the paint off and either way leave them smooth for a re coat ?

[Kelvin]

One of those 3M pads from Screwfix with different grit size either side. I can’t recall which one specifically but I think it was the finest grit size. I’d try the Gardz sealer for problem surfaces before trying to sand it back.