Lateral Bracing for Patio Roof

[AZPE]

I have a custom home and they want a covered patio with heavy timber rafters and heavy timber post and beams. The patio is fairly deep (extends from the rear of the house 16') and they would like to have the beams sit on the posts with decorative "T" straps (similar to the Arch. Simpson "T" straps). I never really have been able to run numbers for lateral support of the structure that satisfied me numbers/code wise because there really is no lateral resisting system in that type of construction other than some knee bracing/kickers from the beam to the post, but from the historical performance that I have seen it apparently works. What have others done to satisfy themselves when it comes to laterally bracing patio roofs or decks (which are essentially the same thing)?

 

[IceNine]

Maybe try using the roof sheathing as a cantilevered horizontal diaphragm.

 

[AZPE]

The problem with that is many times these shed roofs are on a great room wall that has a 14' tall ceiling and the patio has a 10' ceiling and the house diaphragm and the patio roof diaphragm aren't continuous so to cantilever the diaphragm you would have to take the studs in bending to resist the forces, which may be the solution, I just need to run some numbers as well as the connection of the roof system to the studs.

 

[ChipB]

Can you hide your connections inside the heavy timber framing? You'll have to slot the members to put the plates inside, then either bolt or dowel through. You can countersink your bolts and then hide that connection with dowels. I don't know where to get the allowable shear on a wood dowel. I know it's perpendicular to grain, but you'll get other forces involved as well. So I've always used bolts.

Perhaps IceNine could shed some light. He's done this more recently than I. Of course, that doesn't mean he's right! ;-)

 

[IceNine]

Touche ChipB.

I can't imagine the loads would be all that high. Plus, if they're already using decorative steel T straps elsewhere on the project, you could probably come up with a steel connection with a similar character.

Also, try using a parallam column in the wall if the studs won't work.

 

[RARWOOD]

You could also use treated material and embed your post into the fround.