How to build a garden arbor or pergola, with illustrated step-by-step instructions and building plans.
Arbors and pergolas, which are designed to provide relief from the sun’s heat, can be just large enough to shelter a table for two, spacious enough to cover a large deck, or any size in between.
Regardless of size or style, an arbor or pergola not only gives you a shady place to relax or party but can also solve the nagging problem of how to screen your site from above—for instance, to block the view from the windows of your neighbors’ houses or a nearby apartment building.
Building an Arbor or Pergola
The terms arbor and pergola are often used interchangeably, but there is a minor distinction between the two. Although both consist of posts supporting an open roof of beams or lattice, an arbor is broader and may be connected to a building on one side. A pergola, on the other hand, is always freestanding and narrow.
Regardless which of these shade-giving structures you choose to build, the technique is the same. This project is best done with two people. As with any permanent structure, consult your local building department first to determine if you will need any variances or permits.
Materials List
- 6-by-6 posts
- One post base and anchor bolt for each post (if you are affixing to concrete) or one precast concrete pier with post base, plus concrete mix (if building on soil)
- Galvanized nails
- One 1/2-by-10″ lag bolt with washer per post
- Two 1/2-by-7″ lag bolt with washers per beam
- Braces and wooden stakes
- Two 6-by-6 beams
- 4-by-4 rafters
Step-by-Step Instructions
Fasten each post base to the concrete with an anchor bolt (if building on the ground, dig a post hole, fill the hole with concrete, and position the top of the precast pier 3 to 4 inches above grade level). Cut the posts to length if necessary. Nail the posts to the post bases.
Use a level on two adjacent sides to check that each post is vertical. Secure each post in position with temporary braces nailed to wooden stakes driven into the ground.
With a helper, position a beam on top of each post. Check that the posts are still vertical and the beam is level. Use a 7/16-inch bit to drill a 9-inch-deep hole down through the beam into each post. With a wrench, install a 10-inch lag bolt into the hole. Repeat for the other beams.
Set and space the rafters on top of the beams. With a 7/16-inch bit, drill 6-inch-deep holes through the rafters and into the beams. Install a 7-inch lag bolt into each hole. For more strength, you can install diagonal bracing between the posts and the beams.
For shade, cover the rafters with vines or lath, either 1 by 2s or 2 by 2s.
