wind and a pergola

kossetx · Apr 16, 2008

Folks, I want to put a 6' swing down by my pond. I'd like it to only be on 2 legs, 8' between legs with a 6'-8' trellis on top. For the legs I was going to use 6" cedar posts with a 4X4 top rail and 2X4 trellis type canopy for some confederate jasmine to grow on and give us shade.

The question is do you think it will stand up to wind with 2 legs? It can be windy here sometimes. The posts will take it but I wonder about the canopy in the wind.

TIA for any response. Mark

MarkV · Apr 17, 2008

I think you will be fine with an open trellis as far a wind goes. I would consider putting a 2x6 on both sides of your vertical posts with through bolts for a stronger connection and wider bearing point for the 2x4 trellis members rather than a 4x4 set on top. Some blocking bolted between the 2x6's will give strong mounting points for the swing. You will need to set those posts deep and solid. The pendulum affect of the swing, a wide trellis and the future weight of the jasmine is going to require some strong posts.

MarkV

EddieWalker · Apr 17, 2008

The 6x6 posts will be plenty strong for what you have in mind. Just as long as it's a sitting swing, and kids wont be going crazy on it.

I would notch the top of the posts and use a 2x8 for the span. I would also buy one that's 12 feet long and have it extend two feet past the posts on either side. I would brace off of the 6x6 posts for a 2x6x12 three feet away from the center 2x8 to give you your 6 foot wide cover and tie it together with 2x6's notched down two inches over the 12 beams to hold it all together.

I would use screws for all your attachemens except for the main 2x8 beam and angle braces. There I would use bolts.

To attach the swing, I would either loop the chain over the 2x8 beam and fasten it to the beam through the links, or I would get a bracket that will attach to the sides of the 2x8 that you can attach the chain to. I would not screw anything into the bottom of the beam or drill through it for an eye bolt. Both will lead to failure of the beam.

Eddie