How to Build a Pergola for a Dreamy Outdoor Getaway
Image zoom Step 1: Plan Pergola Design and Dig Holes for Posts For a freestanding backyard pergola, plan to sink posts at least 3 feet into the ground. For example, an 8-foot-tall pergola needs posts at least 11 feet long. If possible, bolt some of the posts to existing decking posts or similar strong structural members. Using a posthole digger or an auger, dig the postholes at least 30 inches deep or to the depth required by local codes. Shovel several inches of gravel into the bottom of each hole and insert the posts. (You will cut them to height later.) ...
Source: bhg.com