Nail 2x4 joist headers and
floor joist to 4x4.
4x4-8' Treated
Runner
4x8 Flooring
2x4-15'-9" Joist Header
4x4-8' Treated
Runner
1.
Cut (2) two 2x4-16' to a length of 16' -0". They will be used for the joist headers. Position the
boards together and indicate with 'X' marks where the floor joists will be located.
6.
Install 4x8 flooring over the 2x4s.
Use 8d galv. deck nails.
Material Description
12' x 16'
2x4 Treated Blocks
2 pcs.
8'
2x4 Treated Headers
2 pcs.
16'
2x4 Treated Joist
17 pcs.
12'
4x4 Treated Runners
8 pcs.
8'
Flooring 3/4"
6 pcs. 4x8
Screw Floor Nails
5 lb.
8d
Galv. Box Nails
5 lb.
16d
2x4-2' Treated
Blocks
2.
Cut (17) seventeen 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 the joist measurements
if necessary to obtain 12'-0" building width.
3.
Place 4x4-8' treated timbers on the ground. Cut (2) two 2x4-8' boards into 2' long blocks to
secure the 4x4s where they butt together.
4.
Install the floor joists between the 12' joist headers. Secure with 16d galv. deck nails.
5.
Place floor sections over the 4x4s. Square floor assembly. Measure the floor diagonally (corner
to corner). Then measure the opposite corners. These measurements will be the same if the floor
is square. To keep the 2x4 frame from moving, toenail frame to the 4x4 runners.
Shown below is a typical wood floor. Depending on your area, the construction may have to be
changed to meet local codes. The foundation size should be 12' - 0" x 16' - 0".
Optional Wood Floor System
X
X
X
X
X
X
12"
11-1/4"
X
X
12"
