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Outdoors > Patios > How to Construct an Attached Pergola

Learn how to design and build a pergola that's attached to an exterior wall. Perfect for patio shade.

Homeowners in our project are building an attached pergola over their patio to offer protection from the summer sun. The pergola will be the same size as the patio, designed in simple rectilinear construction with a semi-open roof made of two-by-eight beams set on edge. The structure will have three layers of beams--an initial layer bolted and screwed to four-by-four posts for support, and two successive layers set at alternating right angles to the first and assembled chiefly through interlocking notches.

Step by Step Instructions with Video

Step
1

Determine the Size and Design

Choose the design and appropriate materials for your pergola and assemble your tools. We want the pergola to be the same size as the patio.

Step
2

Measure to Locate the Ledger

Start at one edge of the patio and draw a vertical line up the side of the house to the desired elevation for the pergola. Draw a matching line on the opposite side of the patio. Use a bar level to ensure the lines are perpendicular to the ground.

Step
3

Layout the Ledger Location

Measure the horizontal distance between the lines to determine the outside width of the pergola?s first layer and use a circular saw to cut three beams of corresponding length. (We measured 139 inches, but your project will differ.) Be sure to use safety equipment. The first beam will serve as a horizontal ledger bolted to the side of the house at the back of the pergola. The other two ?end? beams will sandwich the four-by four posts for support, running parallel to the ledger at the front of the structure.

Step
4

Mark the Ledger Notches

Mark positions along the ledger beam?s upper length for the 4 notches that will support the back end of the beams in the second layer. In our project, we locate a notch at the inner edge of each post and two in the middle of the ledger beam separated by the equivalent thickness of a four-by-four (3 5/8 inches). Mark 4 identically positioned notches on all three beams in the first layer.

Step
5

Outline the Notches on the Ledger

Use a combination square and a scrap of two-by-eight wood to trace the shape of each notch at the marks you made in Step 4. The depth of the notches will be half the width of the beam and wide enough to accommodate the thickness of a two-by-eight beam resting on edge.

Step
6

Cut the Notches on the Ledger

Cut out the notches with a jigsaw.

Step
7

Install the Ledger

Level the ledger between the vertical lines drawn up the side of the house and pre-drill two rows of holes for the lag screws, staggering the holes for maximum strength. Secure the ledger to the house with lag screws, tightening them with a ratchet.

Step
8

Position the Post Bracket

Position the first post bracket, ensuring that the location will leave sufficient room to attach a beam on the outside of the post while maintaining the 139-inch overall width of the pergola. Mark the bracket?s center with a hammer and sharp instrument that will leave a mark on the concrete.

Step
9

Drill for the Post Bracket

Remove the bracket and drill a hole in the concrete at the mark. Use a hammer drill equipped with a carbide-tipped masonry bit. The combined action of the hammer drill (pounding and rotating simultaneously) and the carbide-tipped masonry bit will bore through the concrete at a much faster rate and lessen your effort.

Step
10

Insert Post Bracket Anchor

Insert an expansion anchor into the bracket and the concrete and tighten it with a ratchet. When the nut on top of the anchor tightens, the bottom portion will flare out and essentially jam itself in the hole in the concrete.

Step
11

Install Post Bracket

Install a post support in the bracket to elevate the end of the post and stop it from contacting the concrete and moisture that can eventually rot the bottom of the wood. Before actually mounting the post, mark the correct elevation for the roof beams on all four faces of the post at its upper end.

Step
12

Secure the Post to the Bracket

Secure the bracket to the post with a hammer and heavy-gauge galvanized nails.

Step
13

Check for Vertical or Plumb

Check that the post is vertical, using a bar level.

Step
14

Brace the Post in Position

Drive two stakes into the ground and screw a brace to each stake. Clamp the other end of the braces to the post to ensure the posts remain vertical. Each stake and brace pairing must support the post in a different plane to be effective at holding the post level. Repeat steps 8 through 14 for the second post. Verify that both are still vertical.

Step
15

Attach Beam to Post

Align the first end beam on the outer facet of the posts at your roof elevation marks and hold them together with temporary clamps while you use a power drill with a countersunk bit to pre-drill the holes for stainless-steel screws.

Step
16

Install Stainless Steel Screws

Drive the stainless-steel screws into the beams and posts. You will need to use a screwdriver bit holder equipped with a square-ended bit to engage the square drive hole in the end of the stainless-steel screws. These screws are non-corrosive and a great choice for outdoor projects.

Step
17

Attach Second Beam to Post

Install the second end beam on the house side of the posts, repeating Steps 15 and 16, but first fit short scraps of two-by-eight lumber into the notches on both beams to ensure they align perfectly. Verify that the scraps sit properly in the notches and that the bottom of the beam aligns on the roof elevation mark, and then clamp the beams together while you secure the second one with more countersunk stainless-steel screws.

Step
18

Draw Outline for Beam Ends

Draw and cut a decorative curved end on one end of a two-by-eight beam cut for the second layer. The second layer actually has six beams. Be sure to measure the depth of the patio to determine the proper length for the second layer?s beams before cutting.

Step
19

Trace the Outline of the Remaining Beam Endfs

Trace the curve as a template for the single decorative end on each of the other five beams in this layer. These will run perpendicular to the house and the decorative ends will protrude beyond the two end beams. (Save the template/cutout and use if for marking both ends of the eight beams for the third layer.)

Step
20

Sand the Edges

Sand the edges of all the decorative cuts on the six beams for the second layer.

Step
21

Cut Notches on the Beams

Mark and cut notches on the BOTTOMS of four of the six beams, positioned to interlock with the notches on the ledger and two end beams of the first layer. (Two beams will not have notches on the bottom.) Also, cut 8 properly spaced notches on the TOPS of all six beams of this middle layer to match those in the eight beams that will make the third and last layer.

Step
22

Install End Beams

Screw one of the beams (that is un-notched on the bottom) to the outside end of the ledger and the outside facet of the post. Screw the other un-notched beam in similar position on the other side of the pergola.

Step
23

Trim Post Ends

Trim the ends of the posts flush with the top of the beams in the second layer. A Japanese handsaw is an ideal tool for making this flat horizontal cut.

Step
24

Notch Top Layer of Beams

Cut six notches in the bottom edge of the final layer?s eight beams with the jigsaw. (You will have cut these eight beams already and made a decorative curve on both ends.) Make these notches shallower than the notches in beams for layer 1 and 2, so that the final beams sit a little higher and appear more prominent.

Step
25

Fit Beams in PlaceFit Notched Beams Together

Fit the final eight beams into the notches on the second layer and tap them into place with a mallet to ensure that they sit properly in the notches.