12" on center, 18 ft wall
Stud, joist and deck-board layout for a 18-foot run at 12" on center — how many pieces, and where every mark lands measured from the end of the plate.
18 ft wall @ 12" O.C. =
=19 studs
Studs / joists
19
Bays
18
Spacing
12" O.C.
Wall length
18' 0"
How many
A 18-foot wall is
216" long. At 12" on center that's ceil(216 ÷ 12) = 18 bays, and one more stud than bays for the end — 18 + 1 = 19 studs. The same count and marks lay out floor joists or deck boards on the same spacing.Pull the tape
Every mark from the end
| Stud # | Mark (from end of plate) |
|---|---|
| 1 | 0" (end) |
| 2 | 1' 0" |
| 3 | 2' 0" |
| 4 | 3' 0" |
| 5 | 4' 0" |
| 6 | 5' 0" |
| 7 | 6' 0" |
| 8 | 7' 0" |
| 9 | 8' 0" |
| 10 | 9' 0" |
| 11 | 10' 0" |
| 12 | 11' 0" |
| 13 | 12' 0" |
| 14 | 13' 0" |
| 15 | 14' 0" |
| 16 | 15' 0" |
| 17 | 16' 0" |
| 18 | 17' 0" |
| 19 | 18' 0" |
The same math, offline
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