Painting fresh plaster

[Yorky]

When we had our bathroom ceiling replastered the guy recommended that when we painted it the first coat we diluted the paint 50/50 with water, but I can't remember why - we haven't actually painted the bathroom yet but have just had the porch and hallway replastered and the guy didn't mention anything about painting -does anyone know why the 1st guy made his recommendation and what difference it makes to the finish?

Thank you

new plaster sucks all of the water out of paint so you either need to seal it with water and matt paint mixed (andthing from 1part paint to 4 parts water to 50/50 or proper plaster sealer (much more expensive)

if you paint modern emulsion straight onto fresh plaster it will peel off eventually -especially paints such as the scrubable ones

Wow, that was quick.
Thank you workshy - mumsnet is now acknowledged by DH as the source of all knowledge, not just a black hole into which all my evenings disappear

hahaha

Completely agree about the diluted mist coat. Sometimes I apply two. You will know you have killed the suction when the wall no longer pulls the water out of your brush and makes it drag on the surface.

BTW:
Never put PVA adhesive on any surface which you hope one day to paint.

My plasterer recommends getting the cheapest nastiest white matt emulsion you can find for your mist coat as it's already full of water, and then diluting it 50/50 so it looks like skimmed milk.

Mist coating is my favourite

if the plaster is new, it is said that a non-vinyl matt paint (like Dulux Trade Supermatt, but there are other trade paints) is better, because it is more permeable for the plaster to dry out without blistering the paint.

However vinyl paint is more hardwearing.

Silk on top of matt will stick, but matt on top of silk is less reliable unless you rub it down to remove the shine. Silk is easier to wipe clean.