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First post!!!

Very newly qualified so please bare that in mind!!

Recently converted a garage alongside a builder friend. Garage/living annex now has been wired with RFC one lighting circuit. Havent installed yrt but electric underfloor heating and towel radiator (small shower room)
Now what are your thoughts and please explain so i can learn!
I have run 16mm cable from house to garage but nothing connected. I was going to Henley block incoming tails to feed a new CU at house end and new CU garage end. OR could I/ what is stopping me connecting 16mm to current house CU thus preventing installing a new CU off split tails?
Thoughts gratefully recieved
 
That's sounds fine, you could send straight to current cu but depends what you already have in your cu. My pref. Would be to fit to new supply like you said. If its more than 3m from supply to cu I'd fit an isolator at the Henley.
 
16mm implies either a substantial load or a long length to allow for volt drop.
A 50A mcb in your house consumer unit to protect the cable will not really give any discrimination from the mcbs in your garage cu so the answer is usually to use a fuse, something like a 63A in a switch fuse isolator.
Do your cable calcs really dictate a 16mm supply? Maximum demand is usually significantly less than how the OSG advises how to calculate it. For some (high integrity) cus you may be able to get a fuse holder instead of an mcb and fit a 40A fuse. Do a search on here for 'maximum demand', real life experience is likely to be an eye opener.
I would suggest that a non rcd protected swa from the origin connected into a small rcd/rcbo board is what you would be looking for
 
What has your schemes technical support line suggested?
The OP doesn't seem to have left any information in his profile, in which case it is very difficult to see what experience, qualifications or any Scheme membership he has.
 
Thanks - 16mm T&E clipped direct to 1st floor joist then SWA trenched to garage all in all approx 15m. Will be earthed via current earth block at CU
Hi - not meaning to sound funny, but as a learning opportunity perhaps have a cup of tea and a read of Reg 522.6 section in relation to how you've run your cable. See if anything stands out :) .
 
Thanks to all the people who posted with helpful - non-judgemental advice, one of the reasons most of us use forums like this.
 
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i'd be concerned about bonding, esp. if it's PME. that cpc in the T/E will not be large enough to comply.needs 3 core SWA for the whole run.
 
Thanks - i am newly qualified but not registered with CPS so will be third party tested/inspected - just after peoples advice and experience
You dont need to be registered with a scheme to be able to carry out notifiable work. Im not, so i contacted my LABC. They requested copies of all my certificates to see i was competant and then put me on their list of registered electricians. Whenever i carry out notifiable work i have to apply for a building notice certificate from them, this costs £80 regardless of size of job. Long term it would probably be more beneficial for me to be part of a scheme but for now its how i get by.
 
I have just read this thread. (Comp likes to play up on site site). The OP has been given some good points but looks like he has not acknowledged them.
Text is a funny thing and can be interpreted different ways.
 

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