The exact design for the structure depends on the size and shape of the area to be shaded. For this project, a 200 square-foot patio required six posts placed 8 to 10 feet apart to support the structure.
Carefully measure and mark the redwood lumber to correspond with the structure's design.
Carefully measure and mark the positions for the shade structure posts. Make sure their positions are square across the diagonals. Measure from one corner post to the far opposite post (on a diagonal); then measure the distance from the other corner post to its diagonal opposite. The lengths should be the same.
If anchoring the posts in concrete – as with this project – use a concrete hammer drill to anchor the posts at the desired positions using galvinized post bases and expansion bolts (see image).
If not anchoring the posts into concrete, dig postholes, insert and level the posts, then fill the hole with concrete and let dry. Using a post level to make sure each post is plumb and in line with each other.
In some cases it's easiest to attach the structure to the house. In this project the structure is free-standing.
Each pair of posts will be connected at the top by two 2x8 stringers. Measure and but the stringers; cut the ends on an angle (as in the image) to soften the look.
With another person, place one stringer at the proper height (8' or higher at the bottom of the stringer) across two posts. Temporarily screw in one end of the 2x8. Level the stringer and screw in the other end (Image 1). Mount the other stringer on the other side of the posts, parallel to the first stringer; attach it temporarily with 2 inch wood screws and level it to the other stringer.
With the 2x8s held in place (Image 2), drill holes through both 2x8s and each post and secure them using half-inch lag bolts and nuts. Slip a washer over each lag bolt before sliding it through the wood, then add another washer before attaching the nut. Use the same procedure to install the stringers on the other pairs of posts, making sure to level those stringers to the original stringers and to each other.
Shade is provided by laying lateral 2x4 boards across the stringers. Thes boards also receive angle end cuts to provide aesthetic appeal.
Space the 2x4 laterals 6 inches apart across the top of the 2x8 stringers. The laterals should be on edge (tall) to prevent sagging. Secure the laterals to the stringers using wood screws on both sides of the lateral boards.
If desired, apply an exterior-grade wood stain to the structure, following the manufacturer's instructions. When dry, you can apply a clear sealer. If staining, make sure the stain is completely dry before sealing.