Hi all, I have recently had aground floor room plastered and I am having trouble painting it (would you believe!). To start at the beginning the wall in question is an old rubble filled rough stone wall. We hacked all the plaster off and have had it re-plastered. As far as I know the plasters first stabilised the wall with PVA then they applied a 3:1 washed sand cement mix with water-proofer and followed up with two coats of plaster and a skim coat to finish. Now the nature of the wall is such that the depth of material could be approaching 6" in fact I'd say the total depth of material could be anything between 1" and 6" depending upon the profile of the wall. Having read up on how to treat fresh plaster we first left the walls to dry out for 8 weeks. I also realise that with this depth of material it could take months if not years for the walls to dry properly so we decided to hold off with the fancy coloured paint and just go with a few coats of white Dulux Supermatt. I have applied and initial coat of Supermatt diluted to 1:3 water to paint with a roller and this seemed to take to some areas better than others. I waited a day for this to dry and then set about the next coat this time diluted to 1:5 water to paint. This time I noticed small areas of the base coat lifting off as I ran the roller over the surface. Upon closer inspection I could see small regions < 1cm2 where the paint was bubbling. These then lifted off when I ran the roller back and forth over them. Now the paint has dried most of the bubbles are no longer visible although some have cracked and started to peel. I have however noticed that there are small areas on the wall where the back of my finger nail will cause the paint to simply peel off the wall in these small areas of paint seem to be particularly soft whereas in others it seems perfectly hard! Does anyone have any suggestions as to what may be going wrong and how to go about fixing it?