Residential Roof Trusses - 3-pt bearing ?

[ReverenceEng]

Hello all!!

I have a simple hip roof home, simple rectangle, but it's about 45 feet across in the truss (short) direction.

Although I know trusses can span this far, it's going to give me some large beams where we have some large openings on the side. My loads aren't terrible though - Roof dead is about 15 psf anticipated.

I am wondering if this might be a good candidate for 3-point bearing. I have a pretty decent line that goes own the middle of the home - would just require 1 beam and 1 small header, and then of course a continuous foundation, but this is a slab on grade with thickened edge, so nothing terribly cost consuming.

Does anyone have any general rules for when to go for 3-pt bearing? What are some decision points that influence the decision?

Thanks much!

 

[msquared48]

Roof pitch.
Transportability.
Overpass heights.

To name a few...

Mike McCann, PE, SE (WA)

 

[hokie66]

Just remember that a continuous truss will deliver most of the roof load to the internal bearing wall.

And in addition to the issues listed by Mike, they will be spindly to erect. I would think two simple spans are preferable.

 

[CANPRO]

agree with hokie about the two simple spans...that is how I've always done it and seen it done. A quick call to your local truss supplier can be very helpful for questions like this as well.

 

[jayrod12]

I would put my money on the truss guy rather doing it in two trusses as well