how many christmas lights for a roofline
For a roofline, measure each run, add them up, add a 10% allowance and divide by the string length. A 100 ft roofline becomes 110 ft with the allowance, which takes three 50 ft strings and a fourth as a spare. Below are the rules and worked examples.
The eave plus 28 ft of window frames and 20 ft of door frame is 88 ft, or 96.8 ft with the allowance: two 50 ft strings, three with the spare.
With the 10% allowance it is 33 ft, which takes two 25 ft strings.
Three 50 ft strings, and a fourth as a spare if you want one. Without the allowance it would be exactly two.
One bulb per foot of eave, with sockets every 12 inches (30 cm), so 40 ft of eave takes 40 bulbs.
With the allowance it is 44 ft, and 44 / 8 gives 5.5, which rounds up to 6 strings.
About 600 lights for a standard 6 ft tree, which is six strings of 100. The rule is 100 lights per foot of height. A subtle look takes 429 to 514 lights and a packed one 600 to 857. Slim trees take fewer and full trees take more, because the count follows the width.
Govee says 50 or 100 ft may be enough for tiny homes, bungalows and two-story houses, and 100 to 150 ft for larger cottages. That is a rough guide by house size; measuring the eaves, windows and door gives a far safer number.
It is a good idea: Govee suggests one extra string after totaling all the areas, because the first one to fail usually shows up when the ladder is already set up. The calculator leaves the option on and shows the total with and without the spare.
Around the frame: twice the width plus twice the height. A 4 x 3 ft window takes 14 ft and a 3 x 7 ft door takes 20 ft. Enter the count, width and height of each kind and the calculator adds everything to the eave.
Only if the package says the string is rated for outdoor use. Indoor strings are not built for rain and sun; check the label for the intended use, the voltage and the end-to-end connection limit before hanging them.
6 ft 0 in tree, about 41 in wide at the base.
600
6 strings of 100 lights, about 198 ft of wire
Rule: 100 lights per ft of height, times 1.00 for the tree shape (Govee, Christmas Central).
75
Range: 60 to 90
Rule: 12.5 ornaments per ft of height (Christmas Central, Old World Christmas, Christmas in America). Size split from the Christmas in America 7.5 ft chart.
42 ft
Range: 30 ft to 54 ft
Rule: 5 to 9 units of garland per unit of height; the look picks the point in the range (Christmas Central, Old World Christmas).
46 in
Range: 45 in to 47 in
Skirts sold for this height: 48 to 60 in.
Rule: width of the lowest branches plus 4 to 6 inches, 5 by default (Size-Charts.com, House Digest). Widths at 7.5 ft: slim 43 in, full 60 in.
Leave at least 11 3/4 in between the tree tip and the ceiling for a standard topper. Add the ceiling height under More options to check.
Rule: 12 in (30 cm) between the tip and the ceiling (Size-Charts.com).