How to Build an Arbor From Treated Lumber

Stake out a 3x5 rectangle for your arbor. The arbor will be 4x6, but that includes the overhang of the roof--the base/posts of the arbor should be a foot less for visual appeal.

Place an anchor base at each of the four corners of your mapped-out arbor frame. When in place, use a marker or screw to mark or scratch a dot on the concrete within the anchor bolt hole in each of your anchor bases. This will be where the pilot hole is drilled for your anchor bolt that connects the base to the concrete. Once the marks are in place, move the anchor bases out of the way.

Drill a hole with your electric hammer-drill and concrete drill bit straight down into the concrete at all of the four points you marked in Step 2. Drill the holes slightly deeper than the length of the anchor bolt. Holes should also be the same diameter as the bolts. Replace the anchor bases in their original position.

Use your socket wrench to screw the four anchor bolts into the concrete. This will hold the bases in place (which will hold the posts in place). The socket wrench will activate the bolts' locking mechanism and secure them in place.

Place the 6x6 posts into each of the anchor bases. Use a level and T-square to make sure they are perfectly perpendicular to the ground. Screw your screws into each of the holes along the bottom of the anchor bases to secure the bases to the wooden posts. There are usually two screw holes on each side of an anchor base. Do this for all four posts.

Hoist the 6x6 beam onto the top of the posts that make up the 5-foot side of your arbor. Position the beam so it has 6 inches of wood hanging past each of the posts. Once the beams are in the correct spot, put the second beam up on the other two posts. Check the vertical level of the posts once beams are in position.

Drill a 9-inch hole through the beam and into the center of each post, then place a washer on each of the four10-inch lag bolts and screw them into place. You will likely have to use the socket wrench to ensure that each bolt is tightened enough and the beams are secured in place. Do this for each bolt on both beams.

Lift your six rafters onto the top of your arbor. Place them perpendicularly to the beams--they should actually connect the two beams, with one end of the rafter on one beam and the other end on the opposite beam. Spread them so they are 1 foot apart and level. Square them off with the beams at exactly at 90 degrees. As these are also 12 inches too long, space them out so there are 6 inches of overhang on each side of a beam.

Drill a 6-inch hole through each rafter and into the beam below it. Fit a washer onto each of the remaining 7-inch lag bolts and screw them into place, using a socket wrench. Tighten them securely so the rafters are secure. Get down from the top of your structure and enjoy your arbor.