Gloss paint blistering few days after application

[rideforever]

I used Wickes Primer (water based), then 2 coats Wickes undercoat (oil based), leaving 24 hours between coats, then 1 coat of Homebase Weathercoat ... but after a week tiny bubbles are appearing.

Its on the external window sill.

Why could this happen ?

 

[sparkwright]

Possibly applied in damp conditions?

 

[KenGMac]

I was told that the best results were obtained if you used one makers primer, undercoat, and top coats of gloss.

There is a possibility??? that there are some slow acting "conflicting" chemical interactions on-going??

Ken.