I'm starting my backyard renovation project. I've put in a large concrete slab (18'x26'). Now I'm building a Pergola over the slab.
My pergola construction is as follows:
6 - 6x6x10 posts (Grade 1) 12 - 2x12x20 beams (Grade 1)
Posts are held to slab using Simpson Bases anchored into slab Beams are held to posts using notches and double through-bolted on each post
Rafters are 2x8x16 that overlap each other 24" and are through-bolted diagonally at the seams.
The posts,beams, and rafters are built level (no slope)
Above the rafters I have some 2x4x8 runners (sloped)
Above the 2x4x8 I plan to add 2x2 runners
This is my basic construction. I'm experiencing a little flex/sway in the structure but I'm not finished tying it all together yet. I'm using Simpson H2.5 Hurricane straps placed diagonally on every intersecting rafter/beam/runner.
Will adding all of the hurricane straps help tie it all together, or, should I consider some cable tensioning "X" braces on my structure? I was thinking of adding (2) "X" braces if it doesn't stabilize after I'm done adding all my Hurricane ties.
Anyways, any advice (good or bad) you can offer is highly appreciated. This is my first pergola project and I'm not an engineer/carpenter. I'm trying to do it as right as I can realistically do within my budget and skillset, so, be gentle. :-)
The 2x12 Beams Span 13' Between the posts
The 2x8 Rafters Span 11' Between the posts
The 2x8 Rafters are spaced 18 inches on center
The 2x4 Runners are spaced 16 inches on center
The 2x2 Runners will be spaced 12 inches on center