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1930's end terrance house built on soil which is fairly heavy soil/clay. Been living here for years but have noticed a few cracks appearing. One outside and the rest inside.

Outside - cracks goes up to bedroom landing window.
Kitchen - starts near top of wall and goes across.
Frontroom - two horizontal cracks where the wall meets the ceiling.
Landing - one crack which goes down centre of ceiling. Some minor walls cracks.
Bedroom - crack in ceiling where it slopes. Small minor cracks.

I am not very good at DIY, but could have a go at the interior cracks. However, should I contact my insurance company or a builder first? Thanks

Photos: https://photos.app.goo.gl/xn4d6LLdmrZwkBug8

I have a 1930s house built on clay soil and it has worse cracks than that. The worst was about 6mm wide in places.

Outside cracks tend to end up at the corner of a window somewhere as windows concentrate the stress.

Inside I get similar small ceiling cracks. They are either along the interface of the wall and ceiling or at 45 degrees. Cracks at 45 degrees are shear cracks. They indicate things trying to slide past each other.

My own personal opinion is that unless these cracks have suddenly appeared, it's no big deal and you just keep up with them.

Given these cracks are in Artexed ceilings I guess this is the extent of the cracking since , what, 1980-1990? Not very fast at all then.

In the case of my house, I think the cracking has been caused largely bythe north wall being solid brick and having only a few tiny windows in it, compared to the large bays, studding and doors in the other walls.

This causes differential settlement, with the north wall sinking into the clay soil at least an inch over the past 80 years. This doesn't leave a jagged one-inch step in the brickwork somewhere though - the house just kind of deforms and cracks a bit. The roof I think has been left behind a bit - it is still sitting on the walls just fine but I can see a gap in the soffit boards and the movement shows up in the house at the ceiling/wall interface especially upstairs.

I also have slanted doorframes - my front door, back door and toilet door are both close to the north wall so show the distortion the most - the side of the frame attached/close to the north wall has gone down with it but the other frame further away hasn't so much. I have had to trim the door a tad at top and bottom as a result.

As for the bigger cracks - I knocked the pebble dash off and repointed in one case, replaced cracked bricks in the other, then repebble-dashed. I wouldn't recommend knocking off the pebbledash as it requires quite a bit of skill to match it. So, if it were me, I'd fill the interior cracks with something - maybe something flexible - certainly along the wall/ceiling interfaces. I believe you can get flexible fillers. It prevents the filler from cracking again too soon.

Also, I'd try and figure out where your cracks are coming from. It is no doubt due to the clay soil one way or another, but it would be as well to rule a few things out. Have you got a water leak? I had long-term leaks under my outside soil-pipe and gully, but I don't think they were the cause. Do you have differential settlement as I described? Have you got a thirsty tree (like a Willow) close to the house?

As for the outside cracks, You could try and use an exterior grout perhaps. Get something with a sympathetic colour to the pebbledash if possible. Try a small section of crack first to avoid messing your pebbledash up if it goes every (sponge and bucket of water handy?).

Regarding the insurance company. Up to you. I don't imagine they'd underpin your house for the cracks you've shown, if they've taken years to develop. If anyone else knows better though, then fine, take their advice. I'm only guessing about the insurances likely reaction.

PS: That last crack in the Artexed ceiling looks a little like someone stood on that area whilst in the loft!

I don't know how anyone would be able stand on that artex area as it's a slopping roof there and right above the bedroom window. Will that flexible filler work on the artex as the surfaces aren't at the same level or will I have to prop the ceiling up somehow?

I did notice today there was a crack down either side of the landing window from the inside. I might chip away a small area of the outside crack to see if the bricks are cracked too.

Not sure if there is any leak coming in. There is an apple tree some way down the garden so I doubt it. Cold overflow pipe is dripping slightly on flat roof off kitchen. So I doubt it's the problem. Thanks