Ceiling Paint Peeling after Repaint

[Kidbee]

My son repainted the inside of a 25 year old factory made home, a few months ago. He sprayed the existing ceiling paint with an undercoat then a coat of ceiling paint.

Now the ceiling is peeling and also causing the old ceiling paint to lift off with it. See attached photo.

I do not know the science behind this, but is it the molecules in the new paint that are causing this reaction? The tenant says it peels more when the day are hotter.

The next question, is, how do I remove the paint to redo the ceiling? In the areas where it has peeled it will be easy, but what about the areas the have peeled little?

The new spray paint was acrylic.

[FenceFurniture]

What room is it in? If it's a kitchen it could very easily be oil residue from cooking. Was the surface washed down with Sugar Soap before painting? SS remove oil/grease to a certain extent.

Was it plastic paint over enamel (I don't think so)?

One way or another it appears to be inadequate preparation of the surface which is where all the work is. Painting as such is the easy bit.

[Kidbee]

What room is it in? If it's a kitchen it could very easily be oil residue from cooking. Was the surface washed down with Sugar Soap before painting? SS remove oil/grease to a certain extent.

Was it plastic paint over enamel (I don't think so)?

One way or another it appears to be inadequate preparation of the surface which is where all the work is. Painting as such is the easy bit.

All ceilings in the house are affected, but worst in the bathroom. My son says he washed it with sugar soap and does not think that the original ceiling paint would have been enamel.
He did have some last tenants who were smokers. Not sure if they smoked in the house.

[FenceFurniture]

Hmmm, well I think I'm out of ideas. Did he rinse down after the SS wash? I'm not sure how much difference that will make, but I think it's alkaline (feels soapy)

[Big Shed]

Not nearly enough information for me to give an opinion.

What is the ceiling made of?

What was on the ceiling prior to putting on the undercoat?

What undercoat was used - solvent base or waterbase?

Was a good quality undercoat used.?

What was the temperature at the time of spraying on the undercoat and was it very humid?

Same questions for the topcoat.

[Grumpy John]

Not nearly enough information for me to give an opinion.

.........................................
What was the temperature at the time of spraying on the undercoat and was it very humid?

Same questions for the topcoat.

Temperature and humidity are critical.

[aldav]

Some of the 'plastic' paints, as opposed to acrylics are terrible to paint over. The plastic paints were cheap as chips and likely to have been used in situations where price was all important.