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Fitting an outside light without a switch

Hi, i have a live cable at the back of my house, i assume that this is for an outside light as it mid way up the back wall. I would be interested in fitting an outside light but there is no switch inside the house anywhere. The cable just disappears into the outside wall. I guess this is just a premanent source of power? Maybe there used too be a switch but i guess this has been built over? My question is could this cable be re-used for an outside light? Are there such products that dont require a switch? can they be turned on and off another way? Remote contro/ actually on the light itselfl? Are there any products that you can recommended and any advise on fitting.

Thanks for your time,


5 Answers from MyBuilder Electricians

Best Answer

Hi Mark,you could fit one with a pir sensor so it only comes on if its activated by movement,cheap to buy and easy to fit


Answered 23rd Jun 2011

It definitely must be switched. If there is no means of isolation inside, you can always fit a wyse box (remote radio controlled) but it's expensive. Don't forget that anything outside comes under part P of the building regs


Answered 23rd Jun 2011

Hi Mark

I would want to know where the live is fed from!
You can put a external light outside that works off a sensor and usually only comes on as the light fades and something or someone approaches it.But really it should be run off a fused switch for safety!

I would advise to have a electrician look into it for you because its a safety issue and they will advise you the safest option.

Good Luck.
Scott Cannon.


Answered 23rd Jun 2011

There are many light fittings available that are self activated, either with a built in pir (Passive infa red detector) or Dusk till dawn sensor.

Before the light fitting is installed the cable must be identified and tested to ensure safe to do so. We have seen many installations where the cable has been connected to a nearby socket which is clearly NOT safe.

If you are using a voltage tester or indicator that confirms that voltage is present, try turning the breakers (if fitted) off one by one to find out which circuit it is supplied from. It needs to be protected by the lowest rating which will be 6amp. If its not, I strongly advise you to get help.

A good solution for outside lighting is a switched fused spur, as these give local protection and local isolation.

Hope this helps you.

Kind regards



Answered 23rd Jun 2011

Hello mark,
I understand you would like to use an existing cable outside your property for an outside light, which I am glad to inform you that it is possible. Normally, there should always be a switch for a light, but if you cannot locate this switch that is perfectly fine. The product i would recommend for you is a sensored outside light, this is because it never needs to be switched on or off, it uses a constant supply of power (like in your situation) and whenever it detects movement, the light will turn on for a period of time that you require. Also, you can change the lights settings for daylight and night controls to suit your needs.

However, without seeing the cable you've mentioned i cannot ensure this will work for several reasons. They are as follows; the condition of the cable may be poor, the installation of the cable may be incorrect, the cable may not be the correct size/type and there may be an electrical fault on the cable. Also, isolating the supply of the cable may be an issue. On the other hand, if all these issues are checked, the outside light will work perfectly fine.

Kind Regards,

Mr Electric Bham North


Answered 23rd Jun 2011

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