Bracing 6x6 Pergola posts

[VBI]

I am building a pergola off a house. 2 main 2"x 12" beams run perpendicular to the house wall (17' apart) and are properly secured (fixed) to the wall on one end and to a 6x6 post (for each) on the other. These main beams are 17' long and 2x8 beams run accross them at 12"o.c. parrallel to the house wall creating a square pergola fixed at one end on the house wall and to the other on 6x6s.

The questions is, the 6x6 posts were not installed into the ground. They bear on a 6" concrete floor using a simpson connection. I am now concerned about the wind effects and wonder what the best solution is.

a. Installing a 2x12 between the 2 posts (creating a square)
b. Excavating and getting new 6x6s into the ground (creating a fixed end to limit rotation at this point)

Of course I am hoping to hear that solution a will suffice as it would be much easier. Or if there are any other opinions or approaches that I might be missing. I'm sorry if this was not descript enough. I'm giving it a shot.

Thank you if you can help....

 

[Lion06]

What about adding knee braces from the beam connecting the two 6x6 posts to the posts?

 

[swearingen]

Or you could use diagonal bracing in your roof plane to take those loads into the house wall (if the wall and the wall-to-beam connections can handle it).


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[civilperson]

Use the attached building for your horizontal load bracing.

 

[VBI]

Sounds good. Using the roof plane for horizontal load bracing...how would i achieve that?

 

[msquared48]

You will have to check the IRC, as there is an area limitation for cantilevered diaphragms, roof, floor or deck. Above the area listed, you will have to provide more direct means of lateral support, such as the knee bracesw already mentioned.

Otherwise, you will need to make sure the diaphragm nailing can take the shear, and provide tension/compression links to the house at the ends of the diaphragm that are contacting the house. As the connections here impinge on existing wall studs in the residence (as they should), these studs will have to be verified for bending and shear, to include their coneections to the top and bottom wall plates.

Mike McCann
MMC Engineering