How to insulate transition between attic and scissor truss???

[deepstuff]

How do I insulate the transition between attic and scissor trusses? I have 24 feet of attic trusses at the front of my garage and 16 feet of scissor trusses at the back. The end trusses are 2-ply so that I skipped a truss inbetween the two section so that I'd have more ceiling height for stairs. I now have 3'-9" between my last (2-ply) attic truss and my last (2-ply) scissor. How do I frame out and insulate the bay between these two, 2-ply trusses so that I allow space for insulation but also allow increased ceiling height for stairs?

Thanks

 

[p_mori7]

You should post a picture so that we can get a better understanding. Generally speaking, you want the uninsulated zone in the regular trusses and the scissor trusses to be continuous for proper air flow. Does one of your scissor trusses lay against one of your regular trusses ? If so, then add a piece of doubler to the bottom chord of your regular truss, and pieces of doubler on the lower chords of your scissor trusses; in between those frame vertically with 2x4's that will hold your batts.

 

[Shootinok]

A pic would help, but 1st thought is you could add a 2X ledger at the regular truss that matches the profile of the bottom cord of the scissor truss. Then frame between them with horizontal 2X's like purlins.

 

[deepstuff]

Scissor and attic truss have 3'-9" between them so probably have to do as Shootinok suggested. I'll try and post pics later.

 

[ssdave]

I'd put rafters crossing between them at the roof line to span across the 3'9", and insulate it. Then, insulate the vertical section of each of the two doubled trusses with fiberglass batts or rigid foam board.

 

[bowhuntr311]

Following....

Im thinking along the same lines as ssdave is.

 

[deepstuff]

I'd put rafters crossing between them at the roof line to span across the 3'9", and insulate it. Then, insulate the vertical section of each of the two doubled trusses with fiberglass batts or rigid foam board.

So, insulate the section in-between them the same as a wall? insulation tight against the roof sheating?

 

[ssdave]

So, insulate the section in-between them the same as a wall? insulation tight against the roof sheating?

Just like the wall that it is. How is your roof vented, or is it? I'd leave enough room between the insulation and the sheathing to allow air movement, and make sure I had air coming in at the soffits and venting at the ridge. This will make your asphalt roof last longer. If you have steel roof, disregard, you can insulate right against the sheathing as the elevated temperature won't affect it like asphalt shingles.

 

[deepstuff]

These pictures were taken from Attic floor looking towards scissor trusses. Framing started.
https://www.dropbox.com/s/4g6adgszjpaltpn/IMG_4290.JPG?dl=0

https://www.dropbox.com/s/l2g3zo7ym6ztjmi/IMG_4291.JPG?dl=0

https://www.dropbox.com/s/4g6adgszjpaltpn/IMG_4290.JPG?dl=0

 

[bowhuntr311]

You'll need to frame from the last scissor truss over to the first standard truss. 2x4s across that span then you'll need to either use stryofoam insulation board along your last standard truss vertical or fur it out and put batts up against it like your insulating a standard wall. Only need to go the height of the insulation over the scissor truss.