Lounge ceiling cracked

[jakbee]

I live in a 50 year old bungalow and there is a crack across the ceiling from the middle of the chimney breast to the opposiete wall. I have tried filling with various diy products and all have failed. I had it replastered some years back and I thnk that they taped over it and plastered but it came back within a year or so.
I have also tried scrimming myself and plastering over it but this failed as well. I am not a plasterer.
The problem appears to be that this is where two boards meet and only one is secured to the joist.
Does anyone have a solution for me?

 

[PrenticeBoyofDerry]

Can you screw the other board up, waste of time plastering it if the board can sag.
See if you can screw the loose one up, it could be missing the timber so might have to angle your screws towards the fixed board, be careful of pipes and electric wiring though.

Can you get above through floor board and introduce some timber joist so you can fix it, in case no timber is there.

 

[big-all]

assuming its an attic above is there an more than light storage above it!!!

 

[Richard C]

The boards must be well supported or it will always crack open again. If you have a long unsupported edge, it sounds like the boards haven’t been correctly installed. Just tapping it up will not be enough & you need to provide some additional timber support, sistered to the existing joist above.

As stated, cracks can also appear if the loft is used for anything other than light storage & even walking about up there can cause problems if the ceiling joists are slender.