Wondering which is the easier:

TJI floor joists will span from a steel beam in the new garage to an exterior beam, with an 8" SIP between the two beams. (See the attached RTF file for a diagram.) One side of this SIP is inside the attached garage, the other is an exterior. There will be a second floor above both the garage and the exterior space.

The option seems to be to run the TJI over the SIP top plate OR to hang (shorter TJIs) from each side to the SIP. The latter method seems like it would be more energy-efficient but more work.

Comments?

Thanks.

Several questions come to mind.
Is your drawing to scale, with each square being one foot?
Is the SIP wall in question going to be loadbearing?
What is holding up the end of the steel I beam that supports the exterior portion of the I joists?
Do you intend to enclose the underside of the I joists on the exterior side and insulate that area?
As having now asked all these questions, my first response is to say let the I joists fly through over the wall, then insulate between them with expanding foam. However, my real first question is: Why not just bump out the lower floor wall to align with the upper floor walls. Adding several sq. ft of living space without adding substantially to the cost of construction.

Wes --

Thanks for the questions! Here's an update:

1) Is your drawing to scale - No, that's just the MS Word background.
2) Is the SIP wall in question going to be loadbearing? The TJI will have a second floor above.
3) What is holding up the end of the steel I beam that supports the exterior portion of the I joists? Engineer's plan shows a 5" GLB but he has approved using LiteSteelBeam (LSB).
4) Do you intend to enclose the underside of the I joists on the exterior side and insulate that area? Yes - see 2 above.
5) Why not just bump out the lower floor wall to align with the upper floor walls. Mostly because that is the location of the main sewer line and a planned clean-out access. Enclosing this space would leave only 4' between the house and the neighboring wall/fence.

A second engineer here in SLC also recommended going over the top of the SIP.

Thanks for your input.

-- Rick Gregory
    Salt Lake City

P.S. Say hi to MSU for me - I spent a summer there many years ago on an NSF summer program for high school students.