Framing a shed roof sloping 2 directions
I’m a new builder taking on my first custom home project. The architect has drawn up a home with two wings that have shed roofs sloping back toward the house at a 1/12 pitch. Also specified on those roofs sections is a 1/2″/12 pitch sloping toward a conductor head and downspout. The width of the roofs is 20′ so we’re talking a 10″ change from one side to another which seems like a pretty substantial build up to me. They don’t want the whole roof to tilt either just as the shed roof moves toward the valley, so I’m thinking I’d be ripping 2x12s down to make custom shims. There would also be modifications needed on a 4/12″ gable roof that drains to the same valley as these shed roofs where I would need to do a custom build up on that roof plane as well to ensure that it met the tilting shed roof at the same height.
The truss manufactures say they cannot engineer trusses to slope both ways, so all the adjustments would be made in the field.
To further complicate the issue, there are 24″ overhangs on the gable ends and we’d traditionally just drop the gable end trusses 3.5″ inches to accommodate ladder framing but that gets a lot more complicated with all of the roof buildup on those ends.
Just looking on some feedback as far as how to approach this and whether it’s my inexperience making this seem like a problem, the design, or both. Any insight would be great!