Power to the Shed or Garage should preferably be a seperate circuit from the consumer unit. Care should be taken when siting the cables and in the majority of cases SWA (armoured) cable is used to protect against damage. The size of the cable will be determined by the total power required. For garage and sheds we would mostly fit a seperate consumer unit with its own breakers and potetntially its own RCD. This means a fault in the garage or shed does not affect the house circuits. Weather is not as much of an issue as long as everything is sealed and glanded off correctly. By hiring an electrician who is registered as a Competent Person and Part P approved you can be certain that any new wiring will meet the latest standards and you will not have the hassle and expense of notifying the building control as this will be done for you. You will receive notification from the local authority confirming this as well as an Installation certificate, where the work required makes it necessary. Please contact us to discuss your needs and to get a quotation. Phone Brian on 07733104288 or email :brian@bslelectrical