Scissor Truss Shade Structure

Maybe this project would be better posted over at the sister-site home refurbers, but I am so pleased with how it turned out and I am very proud of the joinery.

I have a sort of U-shaped patio on the back of my house that, because it blocks the prevailing wind, is unbearably hot most of the summer. A long time ago I saw someone install a huge high tension shade sail on a TV show and I have been searching for one off and on ever since. I guess they are popular down under, but have not caught on here in the States. Anyhow, I found this shade cloth (not a shade sail) in a Farmtek catalog. They have them in premade sizes, and I believe they are called Aluminet shade cloth. They are rated at 80% shade.

The problem was how to use one of these shade cloths to help my patio. Sketchup to the rescue!!! My U-shape measures 13’ along the sides so now I had the choice of Farmtek’s 13’ X 12’, 15’, or 20’ shades. Sketchup very quickly let me draw back to back triangles with 6’, 7.5’ and 10’ hypotenuses. I settled on the 7.5’ thus the 13’ X 15’ shade cloth ($150). Next, I had to draw a structure that would match those triangles. I settled on a scissor truss system because I wanted it to be strong but also interesting to look at. Sketchup allowed me the confidence to transfer angles and measurements to the 2 X 4s.

All of the joinery is very tight fitting half-laps reinforced with titebond III and screws. The trusses are tied together with a ridge beam along the peak and sit in modified joist hangers on a pair of sleepers along the roof which are raises up by 2X blocks to allow rainwater to go underneath. The shade cloth is then pulled taut and secured to the structure with Farmtek’s “snugger tie down” bungees.

It has been in place for over a year and I absolutely love it!!! It is easily 10-15 degrees cooler under this structure than in the direct sun!