Minimum Pitch for Metal Ribbed Roof

[LS Tractor Owner]

I did a similar "deck cover" as pictured. 2x6 rafters 2' OC, secured to the house, 4x4 posts 4' OC, 2x6 beam across the top of the posts. Ran 2x4 stringers(?) perpendicular across the rafters. Used typical "R" panel roofing. In order to get the most pitch, I dropped the outer edge down to 7' clearance. Ended up with 1 1/2" / 12 pitch. We have had it for over 10 years, no problems. The most snow it has seen is 30" at a time, again, no problems.

 

[Oldoak]

In a situation such as yours (1/2"/12 pitch), I would put down 1/2 inch plywood sheathing down and put the metal roofing on top of that.

 

[lzicc]

I thought about putting a layer of plywood down instead of the strapping to give it more support.

 

[gsganzer]

I'm doing a 6"/12' for a horse stall awning. I'm in N. TX, so snow load isn't typically an issue. I'll also tape the seams where the sheets overlap.

 

[lilranch2001]

I am totally confused what you are asking- it sounds like you are looking for some to validate a contrarian decision. The manufacturer says 3/12.....

What is the roof for? Just a sun shade or is it waterproof cover like the house? If it痴 just a sun shade and the structure can handle the snow in PA and leaking maybe the manufacturer has a different spec.

I壇 be almost as concerned with your connection or detail with the existing roof lines. Between two sheds and the valley I壇 spend some time making sure that was right. Tie into the building and do a proper flat roof with a membrane or don稚 attach it to the building and run the metal for a sun shade.

From my reading of this thread, your bolded comment above seems to be exactly what he is doing

 

[ovrszd]

You'll have no load problems. Worse leak problem you might have is that water running off the eave may try to turn the edge of the tin and come back toward the house. If you give this roof an 1.5" of drop it'll be fine.

Don't worry about "The Sky Is Falling" crowd.

 

[Diggin It]

I have something very similar, but in translucent fiberglass panels. I ran 2x4s on 24" centers from the house to the posts and 1x4s across those to support the panels. They've held 10+ inches of snow more than once with no problem.

 

[Diggin It]

Plywood will just add unnecessary weight and be something to rot from leaks or humidity. If it makes you feel better add extra 1x4s or go to 2x4s for stringers.

 

[ovrszd]

Plywood will just add unnecessary weight and be something to rot from leaks or humidity. If it makes you feel better add extra 1x4s or go to 2x4s for stringers.

I agree. Wouldn't consider plywood at all.

 

[Industrial Toys]

I have almost no pitch on a 72 foot long driveshed. I did not want an imposing roofline at the particular location. The Engineer simply built the truss system accordingly and I even asked for it to be bumped up from that. We are in a high snow area. The building is windswept but I don't think that ever figured into the design.