Carport Wind Loads

[Maine]

I have a 13' wide carport on the side of my garage.

There is a 12" doubled up LVL that runs the entire width of the garage (28') and extends 13' beyond it to catch the carport trusses.

The rear LVL is a doubled up 14" that extends 2' inside the garage for support:

I am concerned with wind load on the structure. The 6x6 support posts are bolted to the concrete bases. I will be installing hurricane clips to the trusses tonight.

I have added bracing per the truss plans (not done when photos were taken).

Thanks for any input.

 

[Maine]

Some more photos:

 

[KELLHAMMER]

What are the design wind loads for your area? Typically from there I would expect to see the following : post piers/footings sized for uplift and over-turning forces. An anchor at the base columns to the footings/ piers with the appropriate sized post base anchor. Strap anchor or bolted connection at the columns to the roof frame beam line. Some diagonal bracing from the columns to the roof structure in column/beam plane are beneficial. Diag. Braces should be more than just toe-nailed in. Roof sheathing needs to be nailed to correct wind standards for your area with properly sized nails and spacing. Roof trusses typically are sized for wind forces in your area by truss manuf. Truss/rafter anchors to beam/ top of walls. The building is structured with the longest face being mostly walled, on the rear making it stiff. But, large garage door openings lack lateral stiffness. Essentially, the walled portion is taking up a portion of the uplift and lateral load of the open portion. Wind pushing against the solid walled areas are still a concern. As much as, the open porch which lacks lateral stiffness and the roof is likely to want to lift off it's foundation. In my area, we design for 90 mph. But, the nearby coastal areas we design for 130 mph. I use a structural engineer for all high wind area design.
From the pictures it looks well put together. The continuous header is a good thing. As are the lapped connection for columns to the beam at the carport. It might be better to thru-bolt rather than just nail that lapped connection

 

[Maine]

Trusses are designed for 120 mph wind loads. (2) Tubes are 30" x 48" deep and the center is 12" x 48" deep with the posts anchored to them.

I will add bracing on the rear opening from the LVL to the rear post, and from LVL to the garage. On the front opening I would prefer not to add bracing as it will take away entry space, but I will add if required.

Also, it seems that I should have a welded bracket fabricated that will tie in the LVL's to the posts and 2x10's that extend rearward supporting the gable end truss with through bolts holding it all together?

Thank you for your input!
Will the addition of a ceiling reduce wind loads? I assume it will but not sure by how much or if it will be enough to warrant expediting the process.

 

[KELLHAMMER]

There are times when the use of a ceiling applied to the bottom of the trusses can provide a beneficial shear diaphragm value to the building. I am uncertain if it will be of any great importance or provide a desired benefit to your particular building at this point. Bracing of three columns will be an improvement on the long side plane of the open porch (gable end). Bracing on the front and rear planes of the open porch are less likely to add significant value, but couldn't hurt if you choose to apply to both. Also, the connection of the bracing is important. Simply toe-nailing doesn't have much value. A lapped and thru- bolted or use of proper straps is much better. Light ga. metal tie down straps are available to do the column to beam connections. Check out Simpson. Like I said, without a true analysis of your building by a local structural engineer for your area's wind load design values, any connection is really just a gut guess. But, any additional bolted or strapped connection is usually an improvement over a simple nailed connection.

 

[Maine]

Thanks again for the input. I will add some plates and through bolt where the bracing meets at the midpoints. I used 6" Simpson SD 1/4" (?) screws for everything.

 

[kbs2244]

I think you are in good shape.
It looks like you have built it in a "hole in the woods."
All those trees around it should be a good wind break.