Planning low-voltage landscape lighting

Low voltage vs line voltage

Most residential landscape lighting runs at low voltage, typically 12 V, supplied by a transformer that plugs into or is wired to a 120 V outdoor circuit. Low-voltage cable is easier to route through garden beds and is far more forgiving if a spade nicks it.

Line-voltage (120 V) landscape fixtures are used for larger properties, tall trees or commercial sites. They need wiring methods designed for burial, deeper trenches and a permit. For most backyards, low voltage is the practical choice.

The parts of a system

• Transformer. Sized for the total wattage of the fixtures plus a safety margin. Many have multiple voltage taps to make up for long runs.
• Cable. Heavier gauge for longer runs and more fixtures.
• Fixtures. Solid brass, copper or heavy cast aluminium with sealed LED modules last longest. Thin painted fixtures crack after a few freeze-thaw seasons.
• Controls. A photocell, timer or astronomical clock turns lights on at dusk and off at a set time. Smart transformers add app control.

Techniques that work

Good landscape lighting is subtle. A few well-placed lights look better than dozens of glowing stakes.

• Path lights guide feet along walks. Stagger them rather than lining both sides like a runway.
• Uplighting shows off a tree or column from below.
• Grazing places a light close to a textured wall such as stone to bring out the texture.
• Moonlighting mounts a downlight high in a mature tree, casting soft leaf shadows on the lawn.
• Step and wall lights recess into retaining walls and stairs, staying clear of snow.

Colour matters outdoors too. Most yards look best around 2700K to 3000K, which flatters brick, wood and stone. Keep one colour temperature across the front of the house so the lighting reads as one design, and match it to your porch lights.

Avoiding voltage drop

Low-voltage cable loses voltage over distance. On a long daisy chain, the far lights get less voltage, so they look dimmer and sometimes warmer in colour than the near ones. LEDs are more forgiving than old halogen landscape lamps, but the effect still shows.

• Use hub or T layouts to keep runs balanced.
• Choose heavier cable for long runs.
• Use the transformer's higher voltage taps for distant runs when the manufacturer allows it.
• Check voltage at the last fixture after installation and adjust.

Edmonton ground, frost and snow

Our soil heaves with frost, and snow can sit on the ground for months. Plan for both.

• Bury cable as the manufacturer recommends and keep it away from where you edge the lawn or dig in beds.
• Use connectors rated for direct burial, sealed against moisture. Most failures are corroded splices.
• Path lights in the snow-shovel zone get broken. Use wall-mounted step lights or keep stakes back from the walk.
• Leave a little slack at each fixture so frost movement does not pull connections apart.

Power, permits and cost

The transformer needs a properly protected outdoor receptacle or a hardwired connection. If you do not have a suitable receptacle where the transformer should go, a new outdoor circuit or receptacle is a job for a licensed electrician and usually needs a permit. Requirements for the low-voltage side can vary, so check with your permit authority or let your electrician confirm.

Cost is driven by the number and quality of fixtures, transformer size, trenching distance, hardscape such as retaining walls and stairs, and whether a new outdoor receptacle is needed.

Our landscape lighting service handles design, power and installation, and pairs well with outdoor security lighting.

Common questions