12" on center, 40 ft wall
Stud, joist and deck-board layout for a 40-foot run at 12" on center — how many pieces, and where every mark lands measured from the end of the plate.
40 ft wall @ 12" O.C. =
=41 studs
Studs / joists
41
Bays
40
Spacing
12" O.C.
Wall length
40' 0"
How many
A 40-foot wall is
480" long. At 12" on center that's ceil(480 ÷ 12) = 40 bays, and one more stud than bays for the end — 40 + 1 = 41 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" |
| 20 | 19' 0" |
| 21 | 20' 0" |
| 22 | 21' 0" |
| 23 | 22' 0" |
| 24 | 23' 0" |
| 25 | 24' 0" |
| 26 | 25' 0" |
| 27 | 26' 0" |
| 28 | 27' 0" |
| 29 | 28' 0" |
| 30 | 29' 0" |
| 31 | 30' 0" |
| 32 | 31' 0" |
| 33 | 32' 0" |
| 34 | 33' 0" |
| 35 | 34' 0" |
| 36 | 35' 0" |
| 37 | 36' 0" |
| 38 | 37' 0" |
| 39 | 38' 0" |
| 40 | 39' 0" |
| 41 | 40' 0" |
The same math, offline
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