Paint peeling off mist coat

[HJT]

I have newly plastered walls in my loft conversion bedroom and ensuite.
I have mist coated the walls and ceiling with 2 coats of 50:50 water and Leyland walls and ceiling matt emulsion.
This has adhered really well.
HOWEVER, any attempt at painting over this mist coat with dulux matt emulsion results in the new paint just peeling off the mist coat like a skin, leaving the mist coat intact.
What can I do? I just want the paint to adhere to the mist coat!
Thanks in advance

 

[Wayners]

Go coat walls with acrylic primer undercoat.
I'd add 5 to 10% water. No more...
Then then Dulux will go over a treat

 

[opps]

You thinned the mist coat too much.

The mist coat is supposed to reduce the level of suction in the plaster. That means when the first full fat coat of paint is applied, the plaster doesn't suck all of the water out of the emulsion. In your case, it is sucking all of the water out because your mist coat did not work as a mist coat.

Unfortunately, there are far too many people on the internet that persist in telling people to go for a 50/50 mix.

The ratio of paint to water is normally printed on the tin.

In the case of Dulux retail paints, they recommend 10 parts paint to 1 part water (9%). Dulux Trade is normally 20% water.

You can either follow @Wayners advice, or just thin the first coat of the Dulux paint (as per the instructions on the tin).

 

[HJT]

That makes sense, thanks. I did what the plasterer told me to do, so thought it would work!
I tried a test with thinned down dulux over the mist coat, but paint still peeled off with masking tape.
I tried another test patch where I put a coat of undiluted Leyland, followed by thinned dulux and that seems to stick.
Now I know the reason for the issue, I don't feel so in despair.
Thanks very much both

 

[Chivas69]

I'm surprised the plasterer didn't tell you to use pva!

 

[opps]

I'm surprised the plasterer didn't tell you to use pva!

For the benefit of the OP- plasters often advise people to seal the new plaster with PVA- never, ever do that.