Surface mounted socket box on top of metal box

30 Mar 2015
Reaction score
United Kingdom
I need to do some trunking and therefore need to adapt the socket so that it’s on a plastic box. This will allow the trunking to slide into the box.

Is there a plastic box I can mount on the existing metal box (set in the wall). Can I pick this up from a DIY outlet?

Thanks in advance
Sponsored Links
Double or single?

There are double boxes designed specifically for this purpose to go over a single metal box.

There are also spacers that can be fitted between the wall and accessory that are come as singles or doubles.

You could get a PVC box. and drill out the fixing holes, and use long machine screws through the accessory, and through the PVC box, and then into the flush wall box.

You can also use a holesaw on the back of the PVC box if wish to make a large hole for extra wiring space.

It's easier to drill a PVC box rather than a standard plastic box.
When using a holesaw on plastic I drill the pilot hole then run the drill in reverse so it does not grab, it gently wears/melts its way through
Sponsored Links
Thanks guys. I purchased the patress boxes from screwfix and by default, they were designed for the electrical screw to continue through the other side. I had some long screws which allowed me to reach the metal socket underneath.

Thanks again

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local