Oops! Small double glazed window surround crumbled

twopenny

I'm thinking that it's probably expansion/contraction of the upvc (whatever) that caused the plaster to go.

It gets direct sun first thing in the summer and during the season then shaded in winter and chill against that wall.

I have caulk.

One set of 'builders' seen to have been gungho with silicone and things not quite fitting, not cutting straight and holes where they got it wrong the first time.

Luckily I'm a good invisible patcher uper but not keen on the number of surprises I'm getting.

Thanks all.

ThisIsWeird

Sounds like it - plaster/filler is pretty brittle, and won't cope with much movement, regardless of how 'flexible' it claims to be...

The only negative with caulk is that it cannot be sanded, so make sure you shape and wipe away any excess before it skins. 

twopenny

Thanks for reminding me.
Been a long time and I'm impatient to get it done so wouldn't have read the directions