Learn how to build a pergola to dress up a patio or outdoor room. This airy yet sturdy structure is a terrific way to finish off a concrete slab, making a wonderful DIY pergola for climbing plants.

By Caitlin Sole
Updated January 21, 2021
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Rather than spending thousands of dollars to tear out a concrete slab and refill it with topsoil, consider building a pergola. Building a backyard pergola attached to the house or a freestanding DIY pergola can be completed in two or three weekends. Pergola materials are also fairly inexpensive.

Both open and covered pergolas provide a beautiful setting for backyard barbecues, fire pits, hot tubs, and more. Ideal for climbing plants, DIY pergolas create an area of dappled sunlight that's ideal for both relaxing and entertaining. You can make it as shady as you like by adding climbing plants and creepers, or by topping off the structure with fabric. The four corners of the pergola can also be anchored with planter boxes. We'll show you how to prep and assemble your own DIY pergola perfect for outdoor living.

wood patio with pergola
Credit: Ed Gohlich

How to Build a Pergola

The following steps detail building instructions for a DIY pergola. Customize your structure with additional pergola design ideas, paint, or stain.

What You Need

  • Wood: 6x6 posts, 2x10s, 2x2s
  • Concrete mix
  • Deck screws
  • Bolts (if attaching to an existing structure)
  • Tape measure
  • Polyurethane glue
  • Posthole digger
  • Gravel
  • Carpenter's level
  • Shovel
  • Backsaw
  • Miter saw
  • Circular saw
  • Clamps
  • Drill
  • Saber saw
  • Chisel
  • Hammer
using spade to dig hole for hostas
Credit: Marty Baldwin

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.)

2 people raising posts for pergola
Credit: Marty Baldwin

Step 2: Set Pergola Posts

Brace the pergola posts temporarily so they are plumb. Use 3- to 4-foot 2x4s or 2x6s at the bottom and 1x4 or 2x4 angle braces anchored to stakes. Getting the posts both plumb and placed at the correct depth may require some shifting, but if you are off an inch or so, it won't be readily visible.

Combine water and bagged concrete mix and fill the postholes. Work the mix up and down with a stout stick to remove all air pockets. Overfill each hole so rainwater will run away from the DIY pergola post.

If your building site allows you to anchor posts to an existing structure, do so using bolts. Take time to ensure the pergola posts are perfectly plumb.

person attaching end joists of pergola
Credit: Marty Baldwin

Step 3: Cut and Install Roof Beams

For a basic garden pergola, the frame supporting the pergola roof consists of doubled 2x10 beams. These four beams create the solid structure supporting the notched rafter pieces.

Prepare for installing the beams by cutting the posts. Mark the cutoff lines on the posts, and be sure to account for the 2x10 beams prior to finalizing the height of the posts. Cut the posts with a reciprocating saw.

Measure the distance between the posts at the top and miter-cut 2x10s for the outer beam pieces. It's OK to bend the posts an inch or two if they are not equidistant.

Working with a helper, place each beam piece so it aligns with the top of each post, and attach them by driving three 3-inch deck screws into each joint. Measure and cut the inside beam pieces. Laminate them to the outside beams using polyurethane glue and 1-1/4-inch deck screws driven every foot.

person setting sub-assembly into place for pergola
Credit: Marty Baldwin

Step 4: Determine Roof Design

A basic pergola roof consists of notched 2x10 lower rafters set perpendicular to the upper rafters. Generally, the lower rafters are 2 to 3 feet longer than the arbor width and the uppers are 2 to 3 feet longer than its length.

The rafters often have decorative ends. Develop a pattern for your rafter ends using a freehand drawing or use a purchased or borrowed pergola plan. The design can be as simple or intricate as you would like.

Next, notch the rafters. For the lower rafters, notch the bottom of each end so the rafters will fit over the beams. The notches should be 3x2 inches.

person attaching upper cleat to sub-assembly
Credit: Marty Baldwin

Step 5: Add On

On top of the lower rafters, cut a notch for the upper rafters to fit into. Cut notches on the bottom of the upper rafters for every lower rafter. Place all rafter notches an equal distance apart.

Cut the notches first with a circular saw, then a saber saw. Clean out the corners with a hand saw and chisel. As you work check to see that the notched rafters will fit tightly together.

person using hammer to build pergola
Credit: Marty Baldwin

Step 6: Raise the Roof

A basic pergola roof consists of notched 2x10 lower rafters set perpendicular to the upper rafters. Generally the lower rafters are 2 to 3 feet longer than the arbor width and the uppers are 2 to 3 feet longer than its length.

The rafters often have decorative ends. Develop a pattern for your rafter ends using a freehand drawing or use a purchased or borrowed pattern. The design can be as simple or intricate as you would like.

Next, notch the rafters. For the lower rafters, notch the bottom of each end so the rafters will fit over the beams. The notches should be 3x2 inches.

person drilling brackets of pergola
Credit: Marty Baldwin

Step 7: Add Finishing Touches (Optional)

If your DIY pergola wobbles, stabilize it with angled braces. Apply two or more coats of stain, finish, or paint to the pergola for long-lasting style.

plants growing in wooden planter at garden
Credit: Peter Krumhardt

How to Build a Pergola Planter

If desired, you can anchor the four corners of your pergola with planter boxes. To build the four planter boxes around the pergola posts, attach 1x4s to 2x2 framing with 1-5/8-inch screws. Butt-join the corners, line with 4 mil plastic sheeting held in place with staples, and cover with 1x4 trim pieces. Top it off with a 1x4 ledge and fill it with soil.

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