I have replaced my garage but it's new location is further away so the cable from the consumer unit is too short. Is it Ok to fit an external junction box to the outside wall and then run the extended cable from that to the garage consumer unit/ RCD? Or do I need to replace the cable all the way back to the consumer unit so it is one long cable to the garage RCD.
Other tips/ advice appreciated, if junction box is ok then where to find one with suitable amps for outdoor mounting.
There are two types of junction that can be buried one used epoxy resin heat shrink and the other cold cast epoxy fill in a plastic case but need the cables ends crimping.
As to junction box on the wall an enclosure which is a plastic or tin box with a hinged lid can be used. And there are some weather proof junction boxes what I am not sure of is how to direct you to correct type without seeing job.
I would pay a visit to local whole sale outlet they are normally helpful be aware if you use crimps you need crimp pliers as well they can be hired at least larger ones.
You don't really give enough info to help you more.
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