Man-made structures, like arbors, arches, pergolas or garden sheds, add visual interest and structure to a backyard landscape, making the backyard plants more interesting and attractive. Arbors also provide shade, space for entertaining or relaxing and privacy, especially when climbing vines cover the sides and top. Homeowners use a variety of materials for arches and arbors, such as treated wood, PVC pipe, found limbs and branches and iron. For this arbor, choose cedar, redwood or any other lumber of your choosing, and plan the dimensions of the arbor before going to the lumberyard.
Figure the dimensions of the arbor. According to "Sunset Garden and Patio Building Book," the minimum height should be 8 feet above ground with posts 3 feet below ground. To obtain the optimum length and width of the arbor, actually position a table and chairs or bench in the desired location and measure the ideal dimensions.
Cut the posts to the desired height and the rafters to the desired length.
Dig four post holes and fill them three quarters full with concrete mixed according to the directions on the package.
Place the concrete piers 3 to 4 inches above the grade of the soil in the holes filled with concrete.
Place the posts in the concrete piers and check to ensure that each post is completely vertical.
Finish filling the holes with concrete.
Secure the posts with temporary braces by nailing them to wooden stakes.
Let the concrete mixture harden for 24 hours before completing the arbor.
Place a beam on top of two posts. Ensure that the beam and the posts are level.
Drill a 7/16-inch hole 9 inches down through the beam into the posts. Insert a 10-inch lag bolt into the hole.
Repeat the installation process for the second beam.
Set the rafters on top of the beams, spacing them approximately 4 to 6 inches apart.
Drill 6-inch-deep holes with a 7/16-inch bit through the rafters into the beams. Insert 7-inch lag bolts in each hole.
Stain or paint as desired.