Painting a ceiling that seems to have a wash on it

[Chaplem]

we have removed some poly ceiling tiles and there seems to be a white wash or something like this on the ceiling, i have pva'd the ceiling but still the paint will not stick i am at a loss as to what to do next can you please help?

[renovator]

We had a similar problem, suggest using alkali resisting primer. Then emulsion as normal. This primer can be obtained from Brewers or similar but is quite expensive. Not sure if pva will cause a problem though.