Hi Guys.
My Son is decorating our front room for us.

Stripped wall paper.
Filled and sanded.
Washed down with Sugar Soap.
Put on a thinned coat of white vinyl matt.
Put on a coat of vinyl matt finish coat.
This coat has dried leaving cracks and crazing, even worst where he cut in
with a brush.
What caused this? paint not thinned enough??

Baz