Shed rafter connection

[jimtheengineer10]

Attached is a plan so you can see what I am talking about. I am reviewing some plans and the contractor has told the owner that it is a bad idea to have such short studs (approximately 16") under the lvl beam. Is this true? Is the lvl beam really necessary or can the rafters be attached to the side of the 2x6 studs?

Does the double 2x12 beam need to carry the floor load and two roofs loads (one from the upper roof and one from the lower roof)? The double 2x12 does not have a support wall underneath it all the way. It clear spans about 11.5'.

Thank you.

 

[Archie264]

Unless I'm missing something the double 2x12 and the LVL beam are not both needed, and, indeed, as shown they are counter-productive in that they form a hinge.

You could block between the studs and use that as your bearing point. If for some reason a ledger board of some sort is needed put it on the face of the studs, not in the middle of the wall where it interrupts the continuity of the studs.

 

[nac521]

Yes, what Archie said. Use LVL's (if calculations prove it necessary) in place of double 2X12. Attach ledger to wall studs and provide some sloped joist hangers for the rafters.

 

[JAE]

See attached for my comments on using sistered cripple studs at each side rafter.

 

[jimtheengineer10]

JAE,
You just put a cripple stud on one side of the 2x6 stud and the rafter would sit on top of the cripple stud?

nac521,
The double 2x12 cantilevers out 4' to support an exterior deck which is why it is pressure treated. LVL's are not supposed to be used for exterior purposes are they as they can't be pressure treated. Am I correct in this assumption or do they make an lvl that can be used on the exterior?

Thanks for the replies.

 

[JAE]

Yes - one cripple per rafter.

 

[nac521]

Parallam Plus PSL is a pressure treated engineered lumber option. Or add cantilevered 2-2X12 PT slightly to the left of the LVL under the wall.

 

[jimtheengineer10]

Am I correct in thinking that the double 2x12 beam needs to carry the floor load and two roofs loads (one from the upper roof and one from the lower roof?

 

[msquared48]

No.

According to the sketch, the double 2X only carries the upper and shed roof loads, plus the weight of the wall above - no, or very little, floor load as the floor joists are parallel to the double 2X.

Mike McCann
MMC Engineering