We had trouble finding a triangle shaped pergola that was big enough (and still within our budget) for the space we wanted, so we decided to build one ourselves from scratch. All of the materials we used were picked up from our local hardware store, and all of the wood was cut and stained from stock. We sketched out a basic plan prior to starting, but did a lot of the design work as we went. Which means a lot of this pergola is customizable for the creative builder! I hope you like it!
Hardware: Post Base - https://amzn.to/3nRTAUa
Deck Joist Tie - https://amzn.to/3nV3NiL
Angled Rafter Hanger (left) - https://amzn.to/3h7LPbe
Angled Rafter Hanger (right) - https://amzn.to/3ern606
3-1/2" Structural Screw - https://amzn.to/3vR1nEH
5-1/2" Structural Screw - https://amzn.to/3uqnVM6
Decorative Washers - https://amzn.to/3uD8alf
Rafter Clips - https://amzn.to/2SAACpL
Lumber (stock dimensions):
Posts - 6" x 6" x 8'
Beams - 2" x 8" x 16'
Rafters - 2" x 6" x 16' and 2" x 6" x 8'
Strapping - 1" x 2" x 8'
The first thing I had to do for this project was to make some concrete footings to give the pergola a solid foundation. Since the pergola is going to be triangle shaped, I poured three footings, each with an embedded anchor bolt to attach the posts to. They will also help hold the structure down to make sure our hard work doesn't end up in the neighbors yard. Our area regularly got winds above 50 miles per hour, so anything not bolted to the ground tends to wander off. You can check out my concrete footings block post for more detailed info on how to make them if you would like to secure your pergola with footings.
Place the base plate on the concrete footing, then place a long board between the two front base plates to make sure they are parallel with each other.
Mark the angle on each side as a guide.
Attach the plates to the footings using a nut and washer threaded onto the anchor bolt and put the cap on top. I like these plates because they have about a 1 inch standoff, which helps keep water a soil away from the wood posts.
Install the front two posts into the base plates.
I'm terrible at cutting freehand, so I made a template to help me keep the ends of all of the headers and beams consistent in their look. Mark the decorative end on the headers using the template you created and cut the design out.
Install the joist ties to the front posts.
Attach the front header to the front two posts using the joist ties.
Attach the rear header using clamps and a level.
Attach the joist hangers to the posterior header.
Use long boards to help set the angle for the back post plate. The faces of the back post are at 45 degree angles in relation to the front two posts.
Install the rear beam.
Cut a 45 degree bevel on the end of the rear beam and insert that end into the joist hanger.
If you are unsure of how much overhang you want with the rafters, cut the end pattern on one of the boards, place it on the beams, and adjust it back and forth until you are happy. Then cut the pattern on the back side to give it the same amount of overhang.
Secure the center rafter with rafter clips.
I recommend making a spacer block to help keep everything consistent. Use the length of the block to space the rafters apart. You can mark on the block your overhang distance to kill two birds with one stone.
Place your cut front end in the intended location to guide where to start the cut for the back end.
Continue this process until all of the rafters have been installed.
Bridge the middle with a 2x6 and angled rafter hangers to decrease racking.
If you used pressure treated lumber, pause here to wait for the wood to dry. Flick water on the boards to test if they are dry enough for stain. If it beads up, they are still too wet.
Stain the pergola as desired. We decided to put shade netting under the rafters. We picked it up by the foot from our local hardware store. We secured to the rafters with a staple gun.
Reattach the rafters on top of the shade netting.
Add 1x2 strapping to reduce the movement of the rafters overtime.
Admire your work!
