Paint cracking on internal side of exterior door

[markwm]

I fitted a brand new hardwood door few months ago, had 2 coats of sadolin wood wood protector and then a couple of top coats of extra. The inside was primed and then painted with Dulux diamond satinwood (water based).

Problem is, as the weather is changing there's massive cracks appearing around the sides of the panels in the door.

Given the price of the paint I assumed it would be decent but it seems to crack at the slightest bit of movement.

Any advice on the best way to repair it? caulk and repaint? or just go over with an oil based paint?

 

[JohnD]

that appears to be a panelled wooden door.

wood expands and contracts with temperature and humidity.

the panels will be fitted into slots/grooves which enable them to move a bit.

the cracking is not the fault of the paint. It gets worse the more coats or thicker paint you have, so can be very bad on old doors that have been frequently repainted without stripping. It will be worse if the outside of the door is dark in colour and faces the sun.

on a hot dry day, scrape the paint out of the joints (I use a 3-corner scraper) and sand lightly. Apply a very thin coat of paint with a very small brush. Try to prevent it building up into a fillet.

Or, after scraping out the old paint from the joint, you can use a narrow bead of flexible filler such as white bathroom silicone, which will stretch with the movement. On white paint it will not be obtrusive to the eye.