Extend garage/utility ring/lights through house to power future conservatory Ask questions and find answers to many subjects relating to electrics and electrical work

[smegleyshire]

My house has a ring and a lighting circuit for the main building supplying both upstairs and downstairs. It also has a separate ring and a lighting circuit supplying the attached garage and utility room. The distribution box for all is located in the garage.

In the future I plan to have a conservatory installed.

My question: Is it OK (or not) to extend the garage ring and lighting circuit through the house to serve the conservatory? This would involve routing it across the rear of the house under the upstairs floorboards.

The main reasoning for doing this rather than just extending the main house circuits is more for the convenience of having power in the conservatory if the main house circuits have to be switched off. It would also make it so that all annexed areas of the property are on the same circuit. The garage/utility ring currently powers the CH boiler and utility washer/dryer. Just wondered if wiring the garage/utility circuits through the "domain" of the main building circuits to reach the conservatory is a "no no" as anybody pulling up the floorboards in future may assume that all T&E under there belongs to the main house circuits.

[Mr White]

There are several factors to be taken into consideration, but the most important question is, How will you test it to make sure it is safe?
Sometimes you have to get a professional in.

[ericmark]

A ring final was limited I seem to remember to 86 meter, and then they altered it from 4% volt drop permitted to 5% so it went to 106 meters.

Also a B32 MCB means it will trip at 32 amp with the thermal part of the trip in the fullness of time, but within 0.01 seconds at 5 x 32 amp when the magnetic part of the trip works B = 3 to 5 times, C = 5 to 10 times and D 10 to 20 times.

The result is the earth loop impedance is important, there are cheap testers with a loop test (£50) but its first light is at 1.9Ω and the pass mark is 1.44 - 5% so lower than the cheap testers measure.

As to if with RCD protection the ELI is really that important is up for debate, however with RCD's we have type AC, A, F, B, and S, having the wrong type when it is secondary is not so important, but when it is the primary protection device then it is important.

In real terms the DIY man/woman can't comply with BS 7671 as the test equipment would make it more expensive than getting an electrician to do the work, I take a chance every time I cross the road, but need to assess the risk.

I can see how busy the road is, and can assess the risk, not so easy with electrics, we should have it all tested every 10 years, 5 years with rented homes, but last time I tested my home was around 15 years ago practising how to do it before taking my C&G 2391 exam which is all about inspection and testing.

Likely as long as all RCD protected to 30 mA you can do what you want, but can't really answer with a forum one needs to assess what is there.