Exterior lighting has often been more about security lights and porch lights but these days it’s more likely to be part of a garden design. The bad news for DIY aficionados is that recent changes to the building regulations concerning electrical work now mean that a lot of it is now out of the hands of the ordinary householder
Impact of Regulations on Exterior Lighting
Electrical lighting and sockets designed for use outside are more robust than usual and are waterproofed. They need to be run back to the fuse board or consumer unit on a permanently fixed separate circuit, and that’s where the regulations come in.
Anything further than swapping out a lamp fitting, switch or plug socket is now subject to building control approval. If you employ an electrician to do the work then they can certify the work themselves (the ‘self-certification’ process). If you do it yourself then you will have to pay to get a building inspector in to certify the work. The cost of this and the hassle involved makes it not worthwhile, so it’s time to get a qualified electrician in.
But there are some parts of installing exterior lighting that can do yourself, then get the electrician in to make all the connections. It’s best to clear this and agree the details with your chosen electrician before you start. Firstly cable needs to be run from the consumer unit to a point where it can be taken outside the house.
Once the hole has been drilled though the exterior wall, the cable should go underground to wherever it’s needed. The buried section of the cable should be made of specially armoured cable. You can also use ordinary twin-core-and-earth but it has to be in rigid black PVC conduit.
Alternatives to Trench Digging
It isn’t always necessary to dig a trench for the cable. You are allowed to run a cable along the side of the house and along garden walls (but not fences). Or you can take it overhead but it has to be at least three and a half metres above ground. This will probably need telegraph poles and supporting wires, something that’s pretty unsightly in a domestic context.
Once the cable is in place leave good lengths at either end for the electrician to hook it up to whatever distribution unit is to be used. You can also put up the exterior lighting units and the switches or sensors to be used and run the cables between them all. Then get the electrician in to connect everything up.
Avoid Cables with Solar Power
You can avoid this hassle altogether by using solar panels to provide electricity. There are many small lights on the market with solar panels built in that will charge during the day and give off light in the evening. But the light is more of a glow than a beam and are really only good for marking out drives and paths.
This is beginning to change with lights that use multiple groups of LEDs rather than incandescent bulbs or halogen units. Because of their lower energy requirements they can deliver sufficient light from a small solar panel mounted nearby and are now becoming available for security lighting
So very soon you won’t have to run a cable under the ground just to light up your garden.