A pergola is an open air structure which is used to define an space for outdoor entertaining. Pergolas have a latticed roof and provide limited shade and little or no protection from the elements. They are commonly used both as a gazebo to house furniture and to create a covered walkway within a garden. Building your own pergola can beautify your garden at relatively little expense.
Contract with a local concrete company to pour a 9 by 9 foot pad. You can use quickset concrete and pour this yourself, but it will have a less glossy finish.
Use a carpenter's square and a chalk line or pencil to mark the locations for the post anchors at each corner of the concrete pad, 8 inches in from the outer edge. When posts are set, this will create a pergola that is an 8 by 8 foot square.
Attach the anchors to the concrete pad using a hammer drill and 1/4-inch screws that will tap into concrete.
Stand the posts up in the anchors, using a level to ensure that they are standing up straight. Drive 2-inch nails through the holes in the anchor and into the post at each corner.
Create a pattern for the ends of each beam. Traditional designs include a curved cutaway and an angular cut across the bottom corner of each beam. The design should be no more than 8 inches tall and 8 inches deep.
Trace the pattern on the end of each 2 by 10 beam using a pencil. The pattern should be aligned with the bottom of the beams, leaving a 2-inch wide section of wood total uncut at the top of the beams.
Cut away the area under the traced line on the 2 by 10 using a jigsaw or circular saw.
Position the first 2 by 10 beam outside of the posts on the east side of the pergola. The beam should be 4 inches down from the top of the post. Use a level to make sure that the beam is level from end to end. Screw it into position at each end using 3-inch long number ten screws.
Position a second 2 by 10 beam, known as a sister beam, on the inside of the posts on the east side of the pergola. Use a level to both insure that the beam is level from end to end, and level with the sister beam on the outside of the posts. Screw it to the inside of the posts using 3-inch long number 10 screws.
Attach a second set of sister beams, one on the inside and one on the outside of the posts on the west side of the pergola. Use the same method to level the beams and screw them to the post as you did on the east side.
Cut two pairs of notches out of the 2 by 6 beams using a dado blade on a table saw. These notches will slide over the 2 by 10 beams. The first notch should be centred 11 inches in from the end of the beam and the second notch should be centred 16 inches from the end of the beam. A second pair of notches should be cut 11 and 16 inches in from the other end of the beam. Notches should be 2 inches deep.
Fold back or cut away the bottom 3 inches of the pattern used to create the design on the end of the 2 by 10 beams, then trace it onto the 2 by 6 inch beams. The bottom of the pattern should be on the bottom of the board, leaving the top inch of board uncut.
Cut away the wood under the traced lines on the 2 by 6 beams using a jigsaw or circular saw.
Set a 2 by 6 beam across the north side of the pergola on the outside of the posts. The 2 by 6 beam should be flush with the top of the posts, with the notches in the beam fitting over the two sets of sister beams on the east and west sides of the pergola.
Bump the board to insure that it fits tightly against the post. Screw a 4-inch wood screw through the top edge of the 2 by 6 beam, and down into the 2 by 10. Use 3-inch number 10 screws to screw the beam to the 4 by 4 post.
Set a second 2 by 6 beam, or a sister beam, on the inside of the posts on the north side of the pergola. The 2 by 6 beam should be flush with the top of the posts, and level with the 2 by 6 beam on the outside of the posts. Adjust the beam so that the notches in the beam fit over the two sets of sister beams on the east and west side of the pergola.
Bump the board to insure that it fits tightly against the post and screw it to both the 2 by 10 beam and the 4 by 4 post.
Set up and attach the sister beams on the south side of the pergola in the same manner as the north side was constructed. Check the level not only between sister beams, but also between beam pairs on the north and south sides.
Set up three pairs of sister beams across the centre of the pergola, running from east to west. The pairs of beams should be on 21-inch centres, with 4 inches between sister beams. The first set of beams should be centred 21 inches from the inner beam on the north side of the pergola. The second set should be centred 42 inches from the inner beam of on the north side of the pergola. The third set should be centred 21 inches from the south side of the pergola.
Screw 2 by 6 beams into position using 4-inch wood screws screwed down through the top edge of the 2 by 6 and into the 2-by-10 beams.
Spray or brush the pergola with a stain and waterproofing agent to protect the wood from the elements.