Most outdoor fixtures are built for a mild climate. Ours is not one.
July in Phoenix has a normal high of 106.6 degrees, and the all-time record is 122. Then monsoon season runs June 15 through September 30, and it brings dust walls and hard rain in the same hour.
So a path light that lasts a decade in Oregon can die here in two summers. Here is what actually survives.
Heat and sun do the slow damage
Our sun is relentless in the worst way. July in Phoenix averages a UV index above 10, which is the top band of the scale.
That light breaks down plastic. Lenses go cloudy and yellow, and housings turn brittle enough to crack when you touch them. Most plastic outdoor lights need replacing in three to five years.
Heat works on the gaskets. The seal around a lens is rubber or silicone, and every hot day and cool night stretches it a little more.
Once that seal hardens, it stops sealing. The light looks fine all summer, then fills with water the first week of the monsoon.
Finishes fail before metal does
Look at how fixtures are warrantied and you can see where the weak point is. Brass and copper are often guaranteed against corrosion for the life of the unit.
The finish on that same fixture usually gets one year. Powder coat and paint are the parts the sun eats.
That is a real clue for a west-facing wall. Pick a fixture where the metal is the finish, not something sprayed on top of it.
Dust gets in before water does
A haboob is dust pushed out ahead of a collapsing thunderstorm. It can blow from any direction and usually lasts a couple of hours.
Fine dust finds every gap. It packs into seams and sits on the gasket, so the seal no longer closes metal to metal.
Then the rain arrives and follows the dust in. Grit first, water second, and a shorted socket after that.
What the IP number tells you
An IP rating has two digits. The first is solids and dust, the second is water.
A first digit of 6 means fully dust-tight. That is the number to insist on here, and it is why IP65, IP66, and IP67 are all the same on dust.
The second digit is where you choose. IP65 handles rain and a rinse from the hose. IP66 stands up to a hard, direct spray.
IP67 survives being under a foot of water for half an hour. Use it for anything low to the ground, near a pool, or in a spot that puddles when the yard drains.
Wet-rated and damp-rated are not the same
Every fixture carries a location rating. Damp means moisture and humidity, but no direct water.
Covered patios, deep soffits, and protected porch ceilings are damp locations. A damp-rated sconce is fine there.
Wet means direct exposure. Open walls, uncovered porches, walkways, and anything the hose or the rain can hit head on.
A wet-rated fixture can go anywhere a damp one can. The reverse is never true, and that swap is one of the most common outdoor lighting failures.
The covered patio rule has a twist here. Monsoon wind drives rain sideways. A patio that stays dry in winter gets soaked in August, so we spec wet-rated there anyway.
Brass first, aluminum second, plastic never
Material decides almost everything about how long a fixture lasts here.
Brass and copper
Both resist corrosion on their own, with no coating to lose. Copper forms a patina as it ages, and that layer shields the metal underneath instead of eating it the way rust does.
They also get better looking. A brass path light goes from bright gold to a soft brown over a few years, and nobody has to touch it.
Powder-coated aluminum
Aluminum is light, strong, and cheaper than brass. It depends on its coating.
Scratch that coating and the metal starts to oxidize under it. A weed-trimmer nick on a path light is all it takes.
It still has a place. On a wall sconce eight feet up, nothing hits it, so good powder coat over cast aluminum holds for years.
Plastic and composite
These are the ones that end up in a trash can. The three to five year replacement cycle is the honest number.
Do the math on a 20 fixture yard, replaced every few years, and cheap fixtures stop being cheap.
The driver is the part that really dies
LEDs rarely burn out. The little power supply behind them does.
Inside that driver is an electrolytic capacitor, and its life runs on a simple rule. Cool it 10 degrees Celsius and the life doubles. Heat it 10 degrees and the life is cut in half.
A capacitor rated for 10,000 hours at its top temperature can stretch far past that if it stays cool. Push it the other way and the same part gives you a season.
Every driver lists a top air temperature it can take. The supply also runs about 20 degrees Celsius hotter than the air near it. So the part inside sees both.
That is why a driver in a sealed box on a sunny stucco wall fails early. It is also why we never bury one in an attic in Queen Creek.
Put the transformer in the shade
Low voltage yard lighting runs off a transformer near the house. Where it goes matters as much as what it is.
We mount at least 12 inches above grade so splash and runoff stay out. Then we leave air on all sides, because it makes its own heat and has to shed it.
North wall, east wall, or under an overhang. Anywhere but the west side of the house in the afternoon.
It also needs to sit within reach of a GFCI outdoor outlet, usually inside six feet. That is a wiring detail worth planning before the landscaping goes in.
Timers and photocells
A photocell turns the lights on at dusk and off at dawn, and it follows the season without anyone resetting it.
It has to see real daylight to work. Tuck the sensor under an eave or behind a shrub and it reads the wrong light level, so the yard comes on at four in the afternoon.
We pair a photocell for the on time with a timer for the off time. Dusk to midnight is the setting most people actually want.
The mistakes that cost a whole system
The same handful shows up over and over on East Valley homes.
Indoor fixtures on a covered patio. Damp-rated cans in a soffit that gets driven rain. Plastic path lights in full sun.
A transformer bolted to the hot west wall is another one.
Buried wire with a twist-and-tape splice instead of a sealed connector, which is fine until the first real rain.
None of those show up the week of the install. They show up in August, usually all at once.
We build outdoor lighting for this climate
We spec brass where hands and hoses reach, wet-rated everywhere the sky can find, and drivers in shade you can get to later.
Start with landscape lighting for paths, trees, and walls, or whole-home lighting if the inside needs work too. If a few fixtures already failed, we handle fixture replacement on its own.
Garrison and Josh work across Queen Creek, Gilbert, Mesa, San Tan Valley, and Chandler. Call (480) 283-5007 or tell us about the yard, and we will walk it with you before the next monsoon.
