I was given some plans for a pergola/patio cover that I would like reviewed and some recommendations and/or comments. I live in the central coast region of California. The weather is usually mild and without snow. Where I live winds are about 10-20 mph, but can get up to 40-45 mph occasionally.
The area I want to cover with the pergola is 23x20. I plan to cover the pergola with a clear plastic of some kind to allow for its use if it rains.
I plan to start with cement 2 feet down and use Simpson products to secure the 6x6 posts to the cement.
On the 20sides I plan to use 3, 6x6 posts spaced 8.5. On the 23 sides I plan to use 4, 6x6 posts spaced 6.6 apart. There will not be any post and beam in the center.
The rest of the plan calls for 6x8 beams secured to the top of the posts around the perimeter. Next, the joist (I believe is the proper name) is 2x8 and will 24 on-center spanning 17 between the beams. I will use knee braces from the post to the beam.
Does this design appear to be correct and strong enough to be safe? My concern is the 2x8s spanning 17 feet as there will be no post or beams in the center of the pergola.
Finally, as I plan to have a local lumberyard deliver the wood I need is there anything about the wood I should look out for?