garage wiring supply Ask questions and find answers to many subjects relating to electrics and electrical work

[mwilson75]

I am looking to feed my garage with electric from my house. The garage is about 8m from the house across a lane. I will need to go overhead with the cable. What is the correct method of fixing a catenary wire between the house and the garage? Will the cable used have to be swa or will twin and earth suffice?

[sparx]

Hi, presuming the 'Lane' has traffic access then guidance note 1 page 196 says the minimum height above ground must be 5.2metres at the lowest point of the catenary.
The strainer wire must be earthed at the house end, and you may use pvc/pvc (twin & earth), armoured would be too heavy to support over such a span without serious support mountings.
If the lane does not have vehicular access then it may be lowered to 3metres, however if it is near a road junction then it must be above 5.8metres.
I am sure you are aware of the bldg regs 'Part-P' requirement for this work and once informed the council may have issues over crossing a public road if indeed it is such,
regards SPARX

[sparx]

one other point, for cables of up to 15mm dia. the fixings must be spaced no more than 350mm apart, I usually go for 300mm and then bind with insulating tape and either old fashioned buckle clips or if not available I use tyraps with the end taken twice round taped cable/strainer and then through hole this gives larger surface area in contact with load, takes a bit of getting used to but imho well worth it.
Don't forget all the wiring in the garage is subject to bldg regs also,
regards SPARX

[mwilson75]

Thanks for the info. Still not sure of best anchors to use to attach strainer wire to buildings. Please advise.

[sparx]

depends on type of building, if brick then expanding rawlbolts with 'Eye' inplace of bolt head are best, if wood then local DIY stores sell plates with 4 screw holes and 'eye' attached, then at one or both ends use a turnbuckle to tighten strainer.
Take 2 turns through eye and use 2 bulldog clamps.
regards SPARX

[mwilson75]

cheers for that. Most helpful