Can I add a power point outside on a patio or deck?

An outdoor socket is not an indoor socket in a different place. It sits in a location where water, dust and insects are expected, so the enclosure carries an ingress protection rating and the installation has to keep that rating intact, including where the cable enters the back of it.1

What an installation involves

• A weatherproof enclosure with a lid that seals with a plug inserted, not only when empty.
• Residual current protection on the circuit, which is required for new work everywhere in Australia.
• Mounting height and position chosen so it is not in a place that will pond water or be hit by a sprinkler.
• Consideration of what will be plugged in, because a socket intended for a pool pump or a spa has additional restrictions.12

Places with special rules

Around a swimming pool or spa, near a shower or bath, and in a garage or carport where a vehicle can strike a fitting, the wiring rules impose zones and clearances rather than leaving it to judgement. This is a normal part of the job for an electrician and it is the reason a socket cannot simply go wherever is convenient.1