The Difference Between Low Voltage and Line Voltage Landscape Lighting
Low voltage landscape lighting runs on a 12-volt transformer and is what we install on nearly every San Diego residential job: safer around kids and pets, cheaper to run, and easy to modify later. Line voltage shows up mostly on commercial sites or a single large fixture tied into house power.
Most homeowners never ask which one we're using. They just want the front walk lit and the palm silhouettes to show up at night. But the choice changes the whole install, from the wire gauge in the trench to how much the electrician bill runs.
We wired a low voltage system on a Carmel Valley property last spring for a client with two dogs that dug through anything shallower than 6 inches. We ran 10-gauge direct burial cable at that depth along the fence line and never had a fixture go dark from a chewed wire.
Why Low Voltage Wins Most San Diego Jobs
A 12-volt system draws less power, so wire can run longer distances before voltage drop becomes a problem. On a typical 2,500 to 4,000 square foot front yard, we can usually run one transformer and avoid a second electrical circuit entirely.
Cost matters too. A low voltage path light runs $45 to $120 installed depending on fixture quality. Line voltage fixtures rated for outdoor use start closer to $150 and need a licensed electrician to tie into the panel, which adds $200 to $500 to a job depending on panel access.
When Line Voltage Makes Sense
We use line voltage on a handful of jobs a year. Commercial lighting near Carlsbad Village is one case, where fixture count and pole height push past what a transformer can handle. A single large uplight on a mature Torrey pine is another, if the client already has an electrician pulling permits for something else on the property.
| Factor | Low Voltage (12V) | Line Voltage (120V) |
|---|---|---|
| Typical use | Residential path, up, and wall lights | Commercial sites, large single fixtures |
| Installer | Landscape crew | Licensed electrician required |
| Install cost per fixture | $45-$120 | $150-$300+ |
| Shock risk if fixture cracks | Low | Higher |
| Wire depth required | 6 inches typical | 18-24 inches, conduit often required |
Does Coastal Salt Air Change the Answer?
It does, some. Fixtures near the coast in Del Mar, Encinitas, and La Jolla corrode faster regardless of voltage. We spec brass or copper housings on anything within a mile of the water and rinse fixtures during irrigation checks. A cheap powder-coated aluminum fixture can pit and fail within two summers out there.
Voltage doesn't fix corrosion. Housing material does. That's a separate decision from low vs line, and we get asked to conflate the two more often than you'd think.
What Does Landscape Lighting Installation Cost in San Diego?
For a typical front and back yard package, 15 to 25 fixtures, transformer, and timer, totals usually land between $3,500 and $8,000 depending on run length and whether we're trenching through existing hardscape or open soil.
Adding smart controls or a phone app tie-in pushes the number up. We don't push those on every client. Some just want a switch by the back door.
Our Recommendation
For nearly every residential yard we touch in San Diego and North County, low voltage is the right call. It's safer, flexible if the planting changes in two years, and doesn't require an electrician every time a bulb needs swapping. Line voltage stays reserved for jobs where scale or a single big fixture demands it.
See our landscape lighting page for more on fixture placement, or check irrigation repair and install if you're planning both systems in the same trench.