Learning to install low voltage landscape lighting is one of the most satisfying DIY upgrades you can make to a home you can make to a home. It runs on just 12 volts — stepped down from your 120V mains by a transformer — which is exactly why you don’t need a licensed electrician to do the fixture work yourself. It’s safe, it’s forgiving, and the results show up the very first night.
Here’s the full process, start to finish.
Step 1 — Plan before you buy
The lights look alluring in the store, and it’s tempting to grab the colors you like and figure out placement later. Don’t. Walk your property first — ideally after dark — map it out, decide which fixtures suit which spots, and divide the yard into zones. The plan comes before the shopping trip, every time.
Step 2 — Buy your fixtures
With the plan set, now buy the lights you mapped out.
Step 3 — Size the transformer
The transformer steps your household voltage down from 120V to a safe 12V. The key rule: keep your total fixture load at or under 80% of the transformer’s rating. Add up the wattage of every fixture, then choose a transformer whose rating leaves that 20% buffer. Residential transformers commonly run from 100W up to 300W, with larger units available for bigger systems.
Step 4 — Mount the transformer
It’s tempting to keep the transformer indoors or tight against the house where it feels safe — but that’s not recommended. Mount it on an exterior wall near a GFCI outlet instead. Keep it switched off the entire time you’re wiring.
Step 5 — Position the fixtures
Lay the lights out in their planned spots before you touch any wiring. For path lights, a common spacing is 8–10 feet apart, staggered on alternating sides for even coverage.
Step 6 — Run the cable
Run the cable from the transformer along your fixture route, and leave some slack — you’ll want room to adjust positions later. Which wire you use matters here: landscape cable comes in 16, 14, 12, and 10 gauge, and thicker wire handles longer runs better. For runs of 100 feet or more, 12-gauge is a common recommendation to fight voltage drop — the gradual dimming that happens when fixtures sit far from the transformer.
Step 7 — Use waterproof connectors
This is non-negotiable. These connections sit outdoors 24/7 through sun and rain, so use proper waterproof connectors: strip, attach, seal. It’s the single most common point of failure, so don’t cut corners.
Step 8 — Test after dark
Before you bury anything, switch the system on after dark and check that every fixture works and looks the way you want. This is your last easy chance to move things.
Step 9 — Bury the cable
Once you’re happy, bury the cable. Sources vary on depth — you’ll see anywhere from 4 to 12 inches recommended, with deeper burial (around 8 inches) advised in mowing zones or high-traffic areas. Check your local code for what’s required in your area. And before you dig, call 811 (the US utility locate service) so you don’t hit a buried gas, water, or power line.
That’s it — you’re done.
A few things worth knowing before you start
Never use extension cords with the transformer. They aren’t safe for this and can create a fire or shock hazard. Plug the transformer directly into its GFCI outlet.
Watch for voltage drop on long runs. If the fixtures farthest from the transformer look dimmer, that’s voltage drop. Heavier-gauge wire and smart layout (splitting long runs into separate legs) are how you manage it.
Conduit isn’t usually required for residential yards, but many areas do require it where cable passes under a driveway or patio. Local code decides — check before you dig.