[bjansen]

I'm planning on installing a shed roof over part of my patio. I plan on using 2x6 lumber for the roof decking. I got the idea to do this roof type after seeing it in a picnic pavillion at a Florida rest stop.

The following link shows the Florida pavillion. http://picasaweb.google.com/lh/photo/GeIew_ruv02YOQ3lVO9W0Q?feat=directlink Notice the spacing between the 2 rafter beams. I measuerd the span between the rafter beams and it was 16'.

I plan on using 6x6 posts in the 4 corners. The spacing between the posts will be 8.5' front to back and 13.5' side to side. I will place a 4x6 on edge on top of the posts running front to back to place the 2x6 decking on.

The question I have is, will the 2x6 decking spanning the 13.5' opening be ok? This seems like a long way for a 2x6 to span laying flat with no additional support...even for a roof with minimal load coming from tar paper and shingles. This is in the Atlanta area, so snow load is not a factor.

Thanks for your thoughts.

--Bob

 

[Scuba_Dave]

At the beginning you say shed roof, then have concerns about a 2x6 laying flat for 13'+
Will it be a flat roof?.....ah - 2x6 's laying flat
I see, I think - So you are going to use 2x6's as the decking
I know for a rafter or joist 13' is too far for a 2x6'

But studs upright at 8' warp & twist

 

[bjansen]

Thanks Scuba Dave.

This is exactly what I thought, but I still can't figure out how they did it in that pavillion in Florida. I really liked the open feel and clean look that it had.

After your comments I ran some numbers through the span calculator at the Amerian Wood Council site for 2x6 rafters. Laid on edge as rafters, the maximum span they can run is 13' 7" set on 24" centers. This is ,with the deflection set to the maximum of L/180. Hmmmm....how did they do this in Florida with the boards laid flat and cover a span of 16'?

Like I say, this is what I would like to do because it looks so clean and open. I just can't figure out, from a structural stand point, how to do it.

 

[Scuba_Dave]

It can be done, it's a matter if it wil last long term
Not sure if they T&G them?

 

[bjansen]

I've decided to put another set of posts with an additional beam in the middle. This will cut the span down to 6'. I will also use the T&G....thanks for that suggestiion Scuba Dave.

The ones in FL have been there for at least 15 years and show no signs of problems. I feel much better using the shorter span.

I'll post pictures when I'm done. It may be a month or two before I get it done though.

--Bob