Electrical Back Boxes

Electrical back boxes generally come in two sizes. One gang (Single) two gang (Double) Single back boxes are used for light switches, single sockets and switch fused spurs.

Double back boxes are used for double sockets.
There are different depths of back boxes depending on what it is used for. Shaving sockets, cooker switches and shower pull cords require deeper back boxes (ideally 47mm).

Light switches (not dimmers) should be 16mm.
Sockets, dimmer switches and fused spurs should be 25mm.

Click here to see how to install a back box correctly

Pictures	Ideal surfaces	Pro's	Con's
	- Brick - Breeze Block - Plaster	- Strong - Tough	- Must use rubber grommets - Hard to chase in the wall - Hard to chase in the wall neat - Must earth back box
	- Brick - Breeze Block - Plaster	- Strong - Tough	- Must use rubber grommets - Hard to chase in the wall - Hard to chase in the wall neat - Must earth back box
	- Plaster board	- Flush to the wall - Very neat and tidy	- Can sometimes see the lip around the edge of socket - The lugs are weak - If plasterboard is too thick it can be difficult to push the lugs out