The previous owner had used glue to attach the switches. The paint has delaminated and the switches are loose.
I want to screw them this time but have no idea what size screw I need. I can estimate the diameter from the screw hole, but what about the length? I'm asking because the wall is aerated concrete and it's hard to find small aerated concrete screws.
It works well with wood screws in lättbetong. Just take one that fits the screw hole. I would guess it needs to be the same length or longer than the box is deep. If it’s not enough, you just need to take a longer screw.
Wood screws work well in lightweight concrete. Just take one that fits the screw hole. I would guess it needs to be equal to or longer than the depth of the box. If that's not enough, just use a longer screw.
Klokit, dosclips or plug and screw. I wouldn't screw directly into the aerated concrete, it will also come loose. Maybe not in a year but in five. Then you'll have nothing left to screw into.
A tip for aerated concrete is to use a PH screwdriver with a shaft that corresponds to the diameter of a red plug (5.5 mm). If you drive it into the aerated concrete, it compacts, and the plug holds very well. Otherwise, it's difficult to get regular plugs to stick well in aerated concrete, if you tighten even a little too much, they will spin around.
Edit: In response to the question, I recommend 4x40 mm screws (not countersunk). Essve used to have something they called an electrician's screw, which was 4.2 mm in diameter. No idea if it still exists but it was good.
I wouldn't screw directly into the aerated concrete, it will also come loose. Maybe not in a year, but in five.
A slightly OT comment:
It's perfectly fine to screw and nail into aerated concrete, but you should always adapt the choice of screw to the material. It holds excellently. In my experience, at least 70 years.
Klokit, dosclips or plug and screw. I would not screw directly into the lightweight concrete, it will also come loose. Maybe not in a year but in five. Then you have nothing left to screw into either.
A tip for just lightweight concrete is to use a PH screwdriver with a shaft corresponding to the diameter of a red plug (5.5 mm). If you drive it into the lightweight concrete, it compacts and the plug holds very well. Otherwise, it is difficult to get regular plugs to sit well in lightweight concrete; if you tighten even a little too much, they will spin around.
Edit: In response to the question, I recommend 4x40 mm screws (not countersunk). Essve used to have something they called an electrician's screw, which was 4.2 mm in diameter. No idea if it's still available, but it was good.
Thanks for the answer! But it was actually concrete and not lightweight concrete. Tried drilling a hole but it didn't go so well because it was so close to the socket!
Thank you! I bought a pair of claw kits but couldn't understand how to use them. The existing box has a smooth surface and the claws do not attach.
You attach the claws to the switch in the designated holes. Then you insert the switch into the box and screw out the claws so they press against the walls of the box. Make sure no wires are in between.
