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How the calculator works
It measures the path the lights take for the pattern you choose, adds extra for the drape, and adds the distance from the first fixing point to the outlet.
- Around the edge: twice the length plus twice the width.
- Zigzag: the lights cross the shorter side several times. More passes give more light and need more length. One pass for every 3 to 4 feet of patio length is a good start.
- X: two diagonals, corner to corner.
- V: from one point on the house wall out to the two far corners. This needs the fewest fixing points on the house.
- One line: a single run along the longer side.
How much extra for the drape
- Taut: no extra. Use a guide wire, or the cord will carry all the load.
- Slight drape: 5 percent extra. This is what most patios in photos have.
- Deep swag: 15 percent extra. Check that the lowest point still clears 7 feet where people walk.
What strand to buy
Outdoor strands come mostly in 25, 48 and 100 foot lengths. Buy the next length up from the result. A few spare feet can be wound around the last pole; a strand that is 2 feet short cannot be fixed.
If you need more than one strand, read the box for the maximum connected run. LED strands usually allow several sets end to end. Incandescent ones often allow only two or three.
Solar or plug-in
Plug-in bistro lights are brighter and stay on as long as you want. Solar strands need no outlet, so set the outlet distance to zero, but the panel needs several hours of direct sun. We go through both, with ten more ways to light a patio, in small patio lighting ideas.
Where to fix them
Each fixing point carries real weight, especially in wind. Use screw hooks into wood or masonry, not into siding or gutters. Where there is nothing to fix to, string light poles in planters or clamped to a railing do the job without drilling.
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