Setting the Posts
Clear an 8-foot-square area of any obstacles where you intend to build the pergola. Mark the four corners.
Measure diagonally from one corner to the opposite corner and record the distance. Repeat for the other two corners. If the layout is square, the distances will be equal.
Dig four holes, one in each corner, for the 10-foot, 6-by-6 inch posts using a post-hole digger. Add 2 to 3 inches of crushed rock to the bottom of each hole.
Position one 10-foot, 6-by-6 inch cedar post in one of the holes. Adjust the post until it is plumb and level and attach temporary braces made from scrap lumber to the post to hold it in place.
Fill the area around the post with dry, fast-setting concrete and 1 gallon of water. Remove the temporary braces once the concrete sets. Repeat this process for the other three corners.
Beams and Rafters
Clamp an 8-foot, 2-by-6 inch cedar board on the outsides of two of the posts to form a support beam. Level the beam and secure it to each post with two 3-inch wood screws. Remove the clamps.
Clamp another 8-foot, 2-by-6 cedar board to the inside of the same two posts. Level the beam and secure it to each post with 3-inch wood screws. Repeat this process for the other two posts.
Drill two holes large enough for the carriage bolts through all four sets of posts and beams. Place a carriage bolt through each hole and fasten it in place with two washers and a nut.
Secure the 10-foot, 2-by-6 inch boards to the inside of the support beams with hurricane clips and hot-dipped, galvanized bracket nails as rafters. Space the rafters evenly along the support beams.
Things You Will Need
- Measuring tape
- Post-hole digger
- Crushed rock
- 4 cedar posts, 10-foot, 6-by-6 inches
- Fast-setting concrete
- Scrap lumber
- 4 cedar boards, 8-foot, 4-by-6 inches
- 12 cedar boards, 10-foot, 4-by-6 inches
- 2 C-clamps
- 16 wood screws, 3-inch
- Drill bit, 3/8-inch
- 8 carriage bolts, 10-by-3/8 inch
- 16 washers
- 8 nuts
- 24 hurricane clips
- 100 hot-dipped, galvanized bracket nails
- Follow the requirements of your local building codes.
- Paint or stain your pergola once it is complete to protect it from the elements.