Cracks round new coving

[Tankboy]

Hi,

Had my son’s room ceiling over boarded and skimmed and the wall skimmed. Left to dry out for 10 days all looked ok nice and pink colour. Have started to give the walls an initial coat with Screwfix No Nonsense New Plaster Paint. Walls and ceiling surface look very good but there are some cracks where the coving meets the ceiling and the wall.

The coving is Pro Cover paper covered polystyrene fixed with Gripfill non solvent adhesive.

I filled the joins with caulk and painted over with Leyland Acrylic undercoat. Though have cracks pretty much at all joins.

Any ideas on how to resolve this?

Thanks.

 

[Bosswhite]

Expansion and contraction whilst drying out, just run a bead of filler along the cracks and wipe smooth

 

[opps]

I don't think the gripfill has cracked. I think that the paint has cracked as the gripfill continues to cure. Waterbased paints often crack when applied over waterbased caulks.

As Bosswhite suggests, run a bead of caulk to hide the cracks. If you simply paint over the new filler with emulsion, the paint may well crack again. Oil based undercoat or Zinsser BIN applied first will prevent the emulsion from cracking.

If you use OB undercoat you will need to wait until the next day before applying the emulsion.

BIN- about 30 minutes before painting with emulsion. BIN is more expensive though and you will need household ammonia to clean your brush.

 

[Tankboy]

Left it for a few days to dry out, sanded all down to smooth cracks and painted over with Polycell crack free paint on the coving. All seems to be ok now.

Thanks,
TB