Dulux Professional 'Durable Flat Matt' paint cracking

[danielwa2]

Hi,
I'm a DIY'er and 2 years ago after our kitchen was remodelled by a professional, including re-plastering, I painted the kitchen by firstly painting the fresh plaster with 2 coats of watered down trade white emulsion as we were recommended to do, then applying 2 coats of Dulux Professional Durable Flat Matt paint which was recommended by our builder. The paint went on lovely and seemed to give us a great finish, however over the last year the coloured paint has begun cracking and peeling off the wall, leaving the watered down emulsion layer underneath. The base emulsion doesn't seem to be chalky or dusty in any way, and there's no signs of damp in the walls, so I'm at a loss as to why it's happened, or what I can do to fix it really. Obviously I guess I need to try and scrape all the coloured paint back off, including the areas not currently cracking, then maybe sealing with something like Zinsser Peel Stop before repainting with the flat matt, but not sure if this is actually something I've done wrong here, or a faulty batch of paint? Any suggestions as to what I've done wrong and what I could maybe do next would be very welcome!

Thanks in advance,
Dan

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[aeromech3]

Not a Deccy but that looks more than typical paint thickness peeling off; each coat is between 60 and 100 micron and 1mm is 1000microns.
What is the approx thickness of the peel as it looks at least 1mm, unless you have a micro lens

[danielwa2]

Thanks for your reply aeromech3. The thickness is less than 1mm, but is quite thick I guess, like I say was only a couple of coats I think. Attached a pic with a tape measure for scale. Maybe I used coats which were too thick then, though I'd have thought that would have caused problems immediately rather than a year down the line?

[aeromech3]

As said I'm not a deccy but it does look that the base coat has not adhered, now the pro's mention mist coat, you watered down 2 coats by how much?
And likely the question was the plaster thoroughly dry.

[danielwa2]

Thanks again for helping, yes it does seem that for whatever reason there has been a reaction between the mist coat and the top coat. The mist coat definitely adhered as where the paint has peeled it's exposed that rather than bare plaster. I did two mist coats of 3 parts paint to 1 part water a couple of weeks after the plastering was done so it certainly seemed to be thoroughly dry.