The basic setup: what you need before you start

Hanging string lights on a patio comes down to three things: a sturdy anchor point on each end, wire or cable rated for outdoor use, and lights designed to stay outside. You do not need special tools or professional help. Most people use one of two methods — either stringing lights between two fixed structures (a house wall and a fence post, or two corners of a pergola), or running them in a zigzag pattern across the patio using posts or hooks you install yourself.

Before you buy anything, walk your patio and identify where the lights will start and stop. Measure the distance in feet. Check whether you have a power outlet nearby — string lights need electricity, and outdoor extension cords must be rated for wet conditions. If your patio has no outlet within reach, you will need to run a cord from inside the house or install an outdoor outlet, which requires an electrician.

The weight of the lights matters. A single strand of LED string lights weighs almost nothing. Incandescent bulbs weigh more and generate heat, so they need stronger support. Most patios can handle either, but if you are hanging lights from vinyl siding or thin wood trim, LED is the safer choice.

Key Takeaways

  • String lights need a power source within reach, and the cord must be an outdoor-rated extension cord if it runs across the ground or along the house.
  • Anchor points must be solid — use lag bolts into wood, concrete anchors into masonry, or existing structures like fence posts and pergola beams.
  • The cable or wire holding the lights should be rated for outdoor use and tightened with turnbuckles or come-alongs so the lights do not sag.
  • LED lights are lighter, cooler, and cheaper to run than incandescent, and they last longer before the bulbs burn out.
  • Sagging lights look worse over time as the cable stretches, so tension matters more than it seems when you first hang them.

Choosing between fixed structures and installed posts

If your patio already has two solid anchor points — the house wall and a fence, or two corners of a pergola — use them. This is the fastest and cheapest route. Drill into the wood or masonry where you want the lights to attach, install a lag bolt or concrete anchor, and screw in an eye bolt. The eye bolt is where the cable will loop through.

If you do not have two existing structures, you can install posts. Metal posts designed for this purpose come in kits and bolt into concrete footings you dig into the ground. A single post costs between $40 and $150 depending on height and material. You will need two posts minimum, one on each end. Dig a hole at least 2 feet deep, set the post in concrete, and let it cure for 24 hours before hanging anything from it.

A third option is to run lights in a zigzag pattern using multiple anchor points across the patio. This works well if you want lights to cover a large area or if you do not have two strong end points. You will need more cable and more anchor points, but the lights will be more evenly distributed and the sag will be less noticeable.

Installing anchor points in wood and masonry

For wood structures like fence posts, pergolas, or the house frame, use a lag bolt with an eye loop. A 3/8-inch lag bolt, 3 inches long, will hold the weight of string lights. Drill a pilot hole first — this prevents the wood from splitting and makes the bolt easier to turn. Use a drill bit slightly smaller than the bolt diameter. Screw the lag bolt in by hand or with a socket wrench until it is tight, then screw the eye bolt into the loop.

For masonry — brick, concrete, or stone — use a concrete anchor rated for outdoor use. A 3/8-inch wedge anchor or sleeve anchor works well. Drill a hole the same diameter as the anchor, tap the anchor into the hole with a hammer, then screw the eye bolt into the anchor. Do not use plastic anchors outdoors; they degrade in sunlight and will fail within a year or two.

Space your anchor points carefully. If the distance between them is more than 15 feet, the cable will sag noticeably even when tight. For spans longer than 15 feet, add a middle anchor point or use a thicker, stronger cable. Stainless steel cable is more expensive than galvanized but lasts longer in wet climates.

Running and tensioning the cable

Once your anchor points are in place, run the cable between them. Use outdoor-rated cable — galvanized steel or stainless steel, typically 1/8 inch in diameter. Do not use regular rope or indoor electrical wire; they will rot or corrode. Thread the cable through the eye bolts at each end, leaving a few inches of slack so you can tighten it later.

Tighten the cable with a turnbuckle, a device that screws in both directions to shorten or lengthen the cable. Attach the turnbuckle to one end of the cable and tighten it until the cable is snug and the lights hang in a gentle curve, not a deep sag. A slight curve is normal and looks better than a completely straight line. If the cable is too tight, it will stress the anchor points and may pull them loose over time.

Once the cable is tight, attach the string lights to it. Most outdoor string lights come with clips or hooks that slide along the cable. Space the clips evenly so the lights are distributed across the span. Step back and look at the result — if the lights sag more than a few inches, tighten the turnbuckle another quarter turn.

Running the power cord safely

String lights need a power source. If you have an outdoor outlet on your patio, plug the lights directly into it. If not, run an extension cord from an indoor outlet. The cord must be rated for outdoor use — look for "outdoor" or "wet location" on the label. Indoor extension cords will degrade and become a shock hazard if left outside.

Run the cord along the ground or along the house wall, away from foot traffic. If it crosses a walkway, tape it down or run it through a cord cover so nobody trips. Keep the cord away from water — do not let it sit in puddles or run through areas that collect rain. If your patio is far from an outlet, consider having an electrician install an outdoor outlet closer to where you need it. This costs $150 to $300 but is safer than running a long extension cord.

Plug the lights into a GFCI outlet if one is available. A GFCI (ground fault circuit interrupter) cuts power when ready if it detects a short circuit, which protects you from shock. Most outdoor outlets are GFCI, but if yours is not, ask an electrician to install one.

Choosing LED versus incandescent lights

LED string lights are brighter, cooler, and more efficient than incandescent. They draw less power, so you can run more of them on a single circuit. They last 25,000 to 50,000 hours before a bulb burns out, compared to 1,000 hours for incandescent. They also cost less to run — an LED strand uses about 5 watts, while an incandescent strand uses 40 watts. Over a summer season, the difference adds up.

Incandescent lights produce a warmer, softer glow that many people prefer. They are also cheaper upfront — a strand costs $10 to $20 compared to $20 to $40 for LED. But they generate heat, which can be a problem if you hang them close to wood or vinyl, and they burn out faster so you will replace bulbs more often.

For most patios, LED is the better choice. The upfront cost is higher, but you save money on electricity and bulb replacements over time. If you want the warm glow of incandescent, look for LED bulbs with a warm color temperature — 2700K to 3000K — which mimic the look of traditional bulbs.

Maintaining and winterizing your lights

String lights left outside year-round will degrade faster than lights you take down in winter. If you live in a cold climate, unplug the lights when you stop using them and store them indoors. Drain any water from the cable and let it dry before coiling it up. Check the cord for cracks or damage before storing it.

If you leave the lights up, inspect them every few weeks. Look for loose connections, frayed cable, or bulbs that have burned out. Tighten the turnbuckle if the cable has stretched and the lights are sagging more than they were before. In winter, snow and ice can add weight to the cable — if you get heavy snow, brush it off to prevent the cable from stretching or breaking.

Replace any bulbs that burn out promptly. A missing bulb can look like a gap in the display, and it may indicate a loose connection that could cause other bulbs to fail. Most string lights use standard screw-in bulbs, though some use proprietary bulbs that only fit that brand — check before you buy replacements.

Frequently Asked Questions

How much weight can a cable hold?

A 1/8-inch galvanized steel cable can hold about 400 pounds, which is far more than any string lights will weigh. The limit is not the cable but the anchor points — a lag bolt in wood can hold 100 to 200 pounds depending on the wood type and bolt size, and a concrete anchor can hold 200 to 400 pounds. For string lights, this is not a concern unless you are hanging something else from the cable as well.

Can I hang string lights from vinyl siding?

Not directly. Vinyl siding is thin and flexible, and a lag bolt will pull through it under tension. Instead, drill through the siding into the wood frame behind it, or attach the anchor to the soffit or fascia board at the roof line. If you cannot reach the frame, use a freestanding post instead.

What if I do not have a power outlet near my patio?

Run an outdoor-rated extension cord from an indoor outlet, or have an electrician install an outdoor outlet on the side of the house closest to the patio. An extension cord is cheaper upfront but less safe if it will be outside for months at a time. An outdoor outlet costs $150 to $300 but is the permanent solution.

How do I keep the lights from sagging over time?

Use a turnbuckle to tension the cable, and check it every few weeks. Cable stretches slightly as it ages and as temperature changes, so you may need to tighten the turnbuckle a quarter turn every month or two. A slight sag is normal, but if the lights are drooping more than a few inches, tighten it.

Do I need a permit to install string lights?

Most municipalities do not require a permit for string lights on a residential patio. If you are installing a permanent post or running electrical work, check with your local building department. Some areas have rules about how high lights can be or how close they can be to property lines, especially if you are renting.