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12" on center, 24 ft wall

Stud, joist and deck-board layout for a 24-foot run at 12" on center — how many pieces, and where every mark lands measured from the end of the plate.

24 ft wall @ 12" O.C. =
=25 studs
Studs / joists
25
Bays
24
Spacing
12" O.C.
Wall length
24' 0"
How many
A 24-foot wall is 288" long. At 12" on center that's ceil(288 ÷ 12) = 24 bays, and one more stud than bays for the end — 24 + 1 = 25 studs. The same count and marks lay out floor joists or deck boards on the same spacing.
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Every mark from the end

Stud #Mark (from end of plate)
10" (end)
21' 0"
32' 0"
43' 0"
54' 0"
65' 0"
76' 0"
87' 0"
98' 0"
109' 0"
1110' 0"
1211' 0"
1312' 0"
1413' 0"
1514' 0"
1615' 0"
1716' 0"
1817' 0"
1918' 0"
2019' 0"
2120' 0"
2221' 0"
2322' 0"
2423' 0"
2524' 0"
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