Replacing metal back box with white plastic sockets

[bigjez]

Hi my house suffers from damp walls in the lounge that have been attented to many times,the metal boxes in the wall get damp and go rusty causing the rcd to trip.

My question is can is it ok to remove and replace the old metal back boxes that keep rusting and replace with plastic surface boxes and switches and fill in the plaster behind , would this meet current wiring regs until the damp in the wall gets sorted?

I have a modern fusebox with rcd's, 2 years old.

 

[Johnmelad]

Get yourself over to the builders forum about your damp problem. Lots of pictures of the wall and outside wall and I am sure the problem can be sorted.

 

[plugwash]

Unless the electrician who installed the sockets has been very generous with the cables I suspect you will find you don't have enough slack to do what you propose.

 

[PrenticeBoyofDerry]

would this meet current wiring regs until the damp in the wall gets sorted?

Well the wiring regs(BS7671) do mention safety, external influences and suitable for environment etc.. So the answer would be no, until you resolve the damp issue.
The only way it could comply is if you installed a suitable IP rated box and plate to prevent the ingress of damp/moisture/water.

 

[sparkwright]

Rusting of the box alone shouldn't cause the RCD to trip. You would need a certain amount of water/damp/moisture for the RCD to trip.

Can't see surface mounted sockets being a major improvement.

Get the damp problem sorted out. Turn off the electricity if things continue to get wet.

 

[bernardgreen]

In cottages with stone walls and no damp proof course it is a good idea to use surface mount sockets as metal back boxes do rust. That said the amount of damp ( from rising damp ) shouldn't be enough to create earth faults bad enough to trip an RCD.

If the sockets are getting wet enough to create a 30 mA earth then the problem may be more than rising damp. Condensation from moisture in the room may be the main source of damp inside the socket.

 

[Adam_151]

Side point, and sorry to take this thread off track, but

In my dad's house there are some walls (stone, I beleive) which do suffer to a small extent with damp, on one of them is a telephone point, from time to time the telephone lines will do dead and the fault always is this telephone socket which looks ok initially, and the K/O box is not rusted, but if you break the plastic rivets holding the PCB to the front plate, you can see where its tracked across, presumably due to the damp atmosphere. The adjacent computer data and twin socket outlet (rcd protected) suffer no ill affects.

Now phone points are lasting approx 1 year dispite me trying various things such as making off the cable and then packing the back of the phone socket with R391 compound, or leaving a pack of silica gel from the packaging of computer equipment in the back of the K/O box.

Anyone got any ideas? I'm at the point of just blanking it off