How to Build an Arbor With 6X6 Posts

Mark a 5x3 foot rectangle on your patio. The roof of the arbor will be 4x6 foot, but it has overhang, so the base needs to be slightly smaller. The process here is for building on a concrete slab.

Place your anchor bases in each of the four corners. Square them off with each other and mark the spot where the anchor bolt hole in each is. The hole should be in the bottom of the anchor base. Simply mark it with chalk or scratch it into the concrete with a nail. Remove the anchor bases after you have the guide marks.

Use your electric hammer drill to drill holes in the concrete at your marks for the four anchor bolts. After drilling four straight holes, replace the anchor bases to the appropriate spots.

Place an anchor bolt into each of the holes you just drilled. The bolts should securely hold the anchor bases to the concrete porch. Use a socket wrench to twist them into place and activate the mechanism at the end of the bolt that anchors it. Do this for all four bases, making sure to keep them level and squared with one another.

Place a post upright into each of the bases. Once in place, level and T-square it so that it will be exactly perpendicular to the ground and roof. Once it is satisfactory, nail two temporary braces into place on each post. These braces should be nailed to the center of the post and angled out toward the ground, where they are wedged in place to hold the post square and vertical. Once the braces are in place, screw or nail the post into place around the bases. There should be two to four screw holes in each base to allow for connection to the posts.

Lift a beam to the top of the arbor. Place the 6 foot beam over the two posts that make up the 5 foot side of the structure. Since there is a foot of overhang, split the difference, with 6 inches of overhang on each side of the posts. Repeat for the other long side. Each of the two long sides of the structure should now look like the symbol for "Pi."

Drill a 9 inch-deep hole through the beam into each of the posts. Drill the hole straight down, through the beam and into the top of the post as close to the center as possible. Do this for each of the four posts. Once the holes are in place, screw in your 10 inch lag bolt with your socket wrench. Make sure to place a washer between the bolt and the wood to prevent cracking and unneeded stress on the wood. Add all four lag bolts into the four holes you drilled.

Place the 6 rafters on top of the two beams. The rafters should be placed perpendicularly to the beams, so that they lay across both beams--essentially connecting the two sides of the arbor to one another. Space them approximately 1 foot apart, level, and squared off with the beams.

Drill 6 inch deep holes through the rafters and into the beams below them. Do this at every intersection between a rafter and a beam (there should be 12 of them). Drill as close to the middle of the rafter and the beam as possible.

Add a 7 inch lag bolt (with washer) into each of the 12 holes on the rafters. Screw them into place with a socket wrench. Remove the two temporary braces from each of the posts. The structure should now be finished, so step back and admire your arbor.