Kitchen wall units - screw size ?

Surely it depends on how much of that screw length is outside the wall, and - if your wall is plaster over brick - how much is in the brick? I think I'd want a couple of inches in the brick part.

If your wall is breezeblock my experience is that that holds screws much less well than brick - though maybe that depends on the fitting used.

When we moved into this house we discovered, when we took the cupboards down to fit a new kitchen, that the wall units were held up with two 1.5" screws at the top of the cupboard, neither of which were tight and one just fell out with minimal tugging! There must have been some science involved in keeping the things on the wall - the pressure pushing against the wall overcoming gravity, or something.

We used 2.5" screws on the new lot, and more of them.

Si