Ceiling and wall cracks

Sounds like you may have lath and plaster on ceilings i would check that first, if so rip it down and plasterboard it.. if not could be boarded and nails have popped on joints, find joist and screw them back up Scrim and skim

someone need to have a look closer on the big crack but about the cracks on the house is better big fiber mesh with plaster that can keep the plaster from craking..

Definitely sounds like old lathe and plaster ceiling, its basically sand and cement, with horse hair in to keep it all together, the crack im the ceiling i wouldn't worry about too much it will need repairing at some point but it wont fall down on you

As others have mentioned in their answers, it certainly sounds like the property could be lath and plaster, and could also be the original plasterwork in addition given the age of the property. As with most ceilings that appear badly damaged, the best cpurse of action is usually an overboard; or what we would recommend, which would be to take the old ceiling down and replace with fresh plasterboards, as this also rules out any issues with your ceiling joists as the timbers become exposed. As for the walls, the same thing applies as to the ceilings if they are stud walls (timber) however, if they are walls plastered straight onto block/brickwork a bonding coat + mesh can be applied over sbr in order to reinforce the wall and stop cracks reimerging once skimmed... or you could take all walls off and dryline/plasterboard. This is only advice, and lots of walls & ceilings should be just fine with a reskim once scrim tape has been applied to problem areas, and the job would obviously need assessing by a pro for evaluation. Hope this helps

It could be structural damage maybe caused by the movement of buildings. It could be excessive heat. These buildings have been there for a long time

Your ceiling is probably original lathe and plaster needs looked at to see if it is cosmetic or if it has came away from lathe it needs taking down and reboarded

In old properties such as yours the ceilings will be lathe and plaster. You can overboard the ceilings and skim, but if it was my house I would rip down all the old ceilings, check the joints are stable then put fresh plasterboard up and skim. With the crack running diagonal across the ceiling along with the wall cracks it could be movement in the building. Again if it was my property I would knock off all the old plaster on the walls and plasterboard and skim. You can try the cheaper way with patching up and skimming but with ceilings and walls as old as yours this can just cause more problems and expense down the road.

In a property of that age, cracks are very common and are often caused by natural movement over time, especially with timber joists and older plaster ceilings. A long, thin diagonal crack is often cosmetic, usually from movement or old repairs failing. Signs it could be more serious would be widening, sagging, or the ceiling sounding loose when tapped. If none of those are present, it’s normally repairable by scrim taping and re-skimming. As it’s in a child’s bedroom, it’s worth having it checked in person for peace of mind.

This would suggest to me the old lath and plaster that over time has compromised. There's a chance it may come lose if the crack continues to open up. My advice would be if allows, to take down the old ceiling back to joists, and reboard and skim. Giving a nice clean finish. If for any reason this is not a valid option it is possible to open up the crack, bond it, apply a mesh and reskim.