long cracks in plaster... is it subsidence?

newbridge

Dear DIYers,
Just found huge cracks going across the ceiling and side wall in room. worries whether it is subsidence or just normal.

- room was skimmed before 1 year. Over a mixture of brick wall and stud(lath plaster).
- When moving furniture a dent was made in the lath wall but no cracks.
- after 2 months found these long cracks seems to be emanating from the dent.

Have never seen anything like this before.Especially being a recently skimmed wall. What is happening in your view and how should i fix them. Thank you!

Warwick_Hunt

Why was it reskimmed?

newbridge

Warwick_Hunt wrote: »

Why was it reskimmed?

It had layers of wallpaper on wall, which were removed and the ceiling had artex. So give it a modern look and able to paint, builder suggested to reskimming

TheCyclingProgrammer

Just hazarding a guess but it’s lossible that when the wall was dented the lath and plaster behind was dislodged, or one of the laths popped slightly. If the plaster was old it could have blown and weakened the skim.

I wouldn’t have thought it’s subsidence, but keep an eye on it.

Jonesya

The fact the cracks converge at the point the plaster was damaged would make me think it's the cause.

They look like hairline cracks so i wouldn't worry about at present, but you could always take a few photos with a ruler in shot to record their width for monitoring. For subsidence I think you'd generally be expecting bigger cracks and cracks starting around door and window frames. You'd also see cracks or movement on the exterior brickwork.

Doozergirl

I suspect it’s blown plaster skim as well as teh cycling Programmer.

Knock on it. Hollow?

FreeBear

Skimming with gypsum plaster (usually the pink/brown stuff) over old lime plaster is never a good idea. Lime plaster tends to be much softer and flexes as a building moves - A key point in timber framed & cob construction (there are other advantages to using lime as well).

Gypsum plasters on the other hand are much harder and less forgiving if the supporting structure moves (either through settlement or thermal contraction & expansion). I note that at least one of these cracks is just above a radiator - The ding in the wall was probably the trigger point and the heat from the radiator has aggravated the situation.