Step B: Build & Install the Corner Posts
Note: Each corner post is made from one full-width 2 × 4 and one 2 × 4 ripped to 2"; the boards are screwed together to form an L. The top ends of both boards are cut at an 18° angle to match the roof slope. The garbage shed also has a center postmade from a single 2 × 4at the rear side of the frame (this is installed in Step C).
1. Rip two 8 ft.-long 2 × 4s to 2" in width. Make an 18° angled cut at about 53", leaving one 43" piece from each. Cut two full-width 2 × 4s at 53" and two at 43", beveling the top ends at 18°.
2. Assemble each front post by placing the cut edge of one 53"-long ripped board against the face of a 53" 2 × 4 so their angled ends are flush (see the FLOOR PLAN and the CORNER POST DETAIL). Drill pilot holes and join the pieces with 3" deck screws driven through the full-width 2 × 4 and into the ripped piece. Assemble the two rear posts the same way.
3. Cut the posts to length with square cuts: Cut the front posts at 49", measuring from the longest point of the angled ends; cut the rear posts at 38 1/4", measuring from the shortest point of the angled ends.
4. Mark the insides of the posts 1 1/2" from the ends. Position each post on the floor frame so the mark is aligned with the bottom edge of the frame. Use a framing square to make sure the post is perpendicular to the frame and clamp the post in place. Drill counterbored pilot holes for the lag screws and washers and fasten each post with two 1/4" × 3" lag screws.
Step C: Frame the Roof
1. Cut two 2 × 4 roof headers at 73". Bevel the top edge of each header at 18° (the broader face should still measure 3 1/2" after the board is beveled).
2. Position the headers between the corner posts so their outside faces are flush with the outside post faces and their beveled edges are flush with the tops of the posts. Toescrew the headers to the posts with 2 1/2" deck screws.
3. Cut two of each type of 2 × 4 rafters, following the RAFTER TEMPLATES. Position the outer rafters between the corner posts so their outside faces and top edges are flush with the outsides and tops of the posts. Toescrew the rafters to the posts with 2 1/2" deck screws.
4. Position the two inner rafters between the headers, 25" in from the outer rafters. Toescrew the rafters in place with 2 1/2" deck screws.
5. If you're building the garbage shed, cut the 2 × 4 rear center post to length so it runs from the bottom edge of the rear header to 1 1/2" below the bottom of the floor frame. Install the center post, centered between the corner posts; anchor the bottom end to the floor frame with lag screws, and toescrew the top end to the rear header.