Cracking in walls

[m0t]

I suspect a lot of these sorts of threads will appear over the next few months given the summer we've just had.

My house is a 1930's semi in SE London (so clay soil).

Over the hot June/July we had a lot of shrinkage of the ground as temperatures stayed so hot and I had large cracks running across my garden you could fit your hand in (now closed up because of the rain).

Over the last couple of weeks I've had some large cracks appear in the house that I'm not sure how to fix.

The cracks have all appeared in partition walls that are made of soft 1930s blockwork that is built directly off the floorboards (so a recipe for expension and contraction).

Most of the cracks I'll just fill with caulk and paint over but I'm not sure what to do in the bathroom because it's cracked the tiles where the partition joins a structural wall. I've got plenty of replacement tiles but now the block has broken am I just going to get cracks in the replacement?

Is there something I can do to the blocks before replacing the tiles?

 

[^woody^]

You likely wont be able to prevent future cracking at that location, without significant repair work.

You need the tile joint to be vertical in line with the lintel, so that when the wall moves it cracks the grout not the tiles. Alternatively, when fixing the tiles, don't apply adhesive to the back of the tile on the smaller side of the crack.