Piggyback trusses

[GeneDavis]

Can any of you ultra-creative Chiefers think of a way to do trusses that are piggybacked?  And have it all be invisible with no roof plane seams when viewing in 3D overview or elevations?

[JiAngelo]

Gene, it took me a minute to figure it out.

Draw your first truss and then draw a general framing member down the length of the ridge line.  Next open a section view of the truss.

Pick a distance down from your peak for your Piggyback Truss bottom chord height + 1-1/2" for laterals = Hip Truss top chord height.

I chose 2'-10.5" and 3'.  Next resize your general framing member to 3.5 x 1.5 and raise it to fit between the chords and copy them to either side like so, 

 

Next select the truss and break it at the 3' line and drag the peak down to the opposite 3' line.  The truss should auto rebuild itself into a Hip Truss.

 

Next go to plan view and draw a second truss farther away and still in the cross section camera view.  Then return to section view and select the new truss you see drawn above the hip truss.  Grab the bottom cord and raise it to the 2' 10.5" line.  Next drag the tails up to the 3' line (so that the piggyback tails rest on the hip truss top chord.

You may need to scroll and zoom to get the moved points in the right location.  The upper truss should have rebuilt itself as well.  Check this in dollhouse view with trusses turned on and next we have to fix the tails.

Select a truss and open the cad detail page for trusses.  Zoom to the piggyback truss.  Below it draw a general framing member about a foot longer in either direction under the bottom chord.  Move this member to 1-1/2" below the bottom chord.  Then use the red circled "Join and Lap Ends" tool twice.  First time click on one top chord, then 2nd time click on other top chord.  (you may need to adjust the member depending on how they snap together)  Then raise the tails to match the top of your member (1-1/2" below the bottom chord.) and delete the member.

  

In plan view move the trusses so that one is on top of the other.  Select both trusses and move them to one end of your building.  While both are selected, multi copy them 24" oc.and make the necessary copy for the end truss as well.  Then look at your seamless 3D views.

 

Note, I actually moved my piggys to a copy of the truss Layer, so that I could turn them on/off separately from the hip trusses.

 

Also, if you select the end hip truss and change it to an end truss it updates automatically.

 

Last note, I tried this first in truss detail view and the hip created fine, but the piggys kept jumping around - it seemed like in detail view the bottom chord always began at the TOW.  In cross section view it gave you more refined control to create the piggys.

 

Hope this helps.