Instructions / Assembly

12' - 0" Building W
idth
To keep 2x4 frame from
moving, toe nail to 4x4.
4x4 Treated Runners
2x4 Joist 11' - 9" Long
2. Cut 2x4-12' floor joist to 11'-9". Treated lumber may be thicker than 1-1/2". Take this into
account when cutting the length of floor joists. Shorten joist measurements if necessary to
obtain 12'-0" building width.
Door Wall
1. Cut (2) two 2x4 joist headers to length. Cut 2x4s to 12'-0" for a 12' long building, 16'-0" for
a 16' long building. Layout for 16" on center joist spacing. 'X' marks where floor joist will
be placed.
4x8
Flooring
Material Description 12' x 12' shed 12' x 16' shed
2x4 Joist Headers 2 pcs. 12' 2 pcs. 16'
2x4 Floor Joist 10 pcs. 12' 13 pcs. 12'
4x4 Treated Runners 4 pcs. 12' 8 pcs. 8'
Flooring 5/8" or 3/4" 5 pcs. 4x8 6 pcs. 4x8
Screw Floor Nails 2 lbs. 8d 2 lbs. 8d
Galv. Box Nails 1 lb. 16d 2 lbs. 16d
Joist Header 12'- 0" for 12' building
16'- 0" for 16' building
X
X
X
X
X
X
16"15-1/4"
2x4 Joist Header
X
X
16"
It is important that the floor be level and square. Square the floor as follows: before nailing the
flooring, measure the floor diagonally (corner to corner). Then measure the opposite corners.
These measurements will be the same if the floor is square.
4x8
Flooring
4x4
Flooring
12' - 0" or 16' - 0" Length
Constructing Details for Deluxe Floor System
Deluxe floors include 4x4 runners, standard floors do not
Check local building codes in your area, the construction may have to change. For a concrete slab,
install sill sealer as a moisture barrier between the concrete and the wall plates. Foam sill sealer can
be purchased at home centers in rolls 3-1/2" or wider.