Hanging patio string lights so they stay where you put them

Let something else carry the load

On any span longer than a couple of metres, run a separate line between the fixed points and attach the lights to it. The line takes the tension; the light cable simply hangs from it and carries no load at all.

This solves three problems at once. The lights are not stretched, so the sockets are not being pulled apart. The sag is set by the line rather than by how hard you pulled. And taking the lights down for repair or storage does not disturb the fixings, because the line stays up.

Sag is a specification, not a failure

A string pulled straight looks wrong and stresses everything; a string with a deliberate catenary looks right and carries almost no tension. Plan for it, because it changes how much length you need.

Height matters as much as length. Hang high enough that the lowest point of the sag is clear of anyone standing under it, and remember the sag increases slightly as the cable warms and settles over the first few days. Set it a little higher than looks right on day one.

Which string suits which span

The Twinkly Festoon is the overhead choice: 20 bulbs over 32.8 feet works out to 19.7 inches between them, which is the wide spacing that reads as a cafe string rather than a fairy light. Its tunable warm-to-cool white is the feature that earns its place on a patio, because the same run has to suit a July evening and a December one.

The 250-LED tunable string is the pick for wrapping a pergola frame or running along a rail rather than spanning open air — 65 feet at close spacing, same warm-to-cool control. Note its published IP44 rating: rain, not immersion, which means it belongs where water runs off rather than pools. The full ranking and the run-length arithmetic are on patio string lights.

Fixing points, in order of preference

Getting power to the patio

Decide where the power comes from before anything goes up, because it determines which end the run starts at — and a string installed from the wrong end leaves you ten feet short at the plug.

A 50-foot 14 AWG outdoor cord publishes 15 A / 1875 W with an ETL listing, which is the headroom you want on a main run that will also be asked to feed something else eventually. Where the run only ever carries LED lighting and you would rather not see it crossing a lawn, the green 16 AWG SJTW cord at a published 13 A is the tidier choice. The gauge argument is on extension cords by gauge, and the safety practices — drip loops in particular — are on outdoor light safety.

The install order

• Measure the span and the perimeter; add 10 percent for sag.
• Decide the power end first, then work the layout from it.
• Fix both anchors before running anything.
• Run the support line and tension it, not the lights.
• Hang the lights from the line, working from the power end.
• Plug in and check the sag height with someone standing under it.
• Put the whole run on a timer — see outdoor light timers.
• Leave it a few days, then re-check the sag once it has settled.

Patio lighting is the one thing on this site that does not go into a box in January, which changes what is worth paying for — that argument is on outdoor lighting that stays up all year.