Horizontal cracks at the top of walls.

[Grenage]

Hi there,

We've been decorating our house, and a couple of the bedrooms had thin cracks along the join between the wall and the ceiling - around 1 cm down from the plaster board; the walls are plaster. The cracks are not perfectly straight, moving up and down within a cm space. The cracks in one bedroom extend around the entire room, but in another room, it extends across one wall - these rooms are on opposing sides of the house.

I'm not concerned that they may be structural, but when I decorated, I opened and filled these cracks, then painted as normal - this was a few months ago.

The cracks are back! Should I have used caulk, or approached it differently?

 

[Micilin]

Are they on the top floor only , does the bit above the crack sound hollow?
Is tehre any movement

It may be where the gap between the timber wall plate and the blockwork below has not been bridged by eml or a wide scrim, or it may be that teh scrim from the ceiling has not come down enough onto the wall plate.


If the plaster is sound , then I would put a 100mm fibatape along it, and cover with easifill, feathering into the wall . This fibatape ideally needs to be bedded into easifill, preferably having prepared with PVA as a sealing coat and then next day an adhesive coat.

Pics would help and I would only do any remedials after you make sure there is no movement and all is sound

 

[Grenage]

Hi there,

Thank you for your advice; I suspected I'd have to dig out the top, tape and fill. I've been into a couple of other houses in our area (same build, ex-council) and they've all had this to varying degrees. Most of the rooms having coving, and this problem either doesn't occur, or is masked.

The plaster is a bit blown in areas - particularly the two rooms I mention. I'd rip it all out, but we're going to move early next year!

At least I now know, should I encounter this at the next place.