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Robert A. Kuzmick
06-27-2007, 02:22 PM
I have a problem and need some advice. I'll try to explain the best that I can. I just purchased a cabin in N.Y. It is 20' deep by 25' wide. The roof sysytem was built with 2x4 trusses. The first 10' left to right by 20' deep are 2 bedrooms(10x10 each) with intact trusses overhead. The next 15'(left to right) by 12' deep (Living Room) has trusses with the bottom chords cut to vault the ceiling. THe previous owner sistered 2x8's along side the 2x4 truss rafters to the peak, there is no ridge beam or rafter. Behind the living room is the bath(7' wide x 8' deep) and the Kitchen (8 wide x 8 deep). The roof pitch is 5/12.
My plan is to install rafter ties 1/3 up from ceiling heighth (2x6) and 1/2 inch plywood gusset at the ridge to correct this issue. Is that enough? Any other thoughts? Can I leave the intact trusses alone?
Also, there is a beam running from kitchen through bath on top of bearing wall that has the opposite side truss chords that he cut attached to the beam. Any help would be greatly appreciated.

Jim Luttrall
06-27-2007, 02:33 PM
Sounds like you are making a good start, but I am having trouble visualizing the issue. We need some pictures.
When they cut the bottom chord, they destroyed the integrity of the truss, so basically you have some 2x4's trying to do the job where a much larger structural member is needed. Normally this is where getting a SE to design a fix would be the best solution.

Robert A. Kuzmick
06-27-2007, 02:50 PM
Thanks Jim, I wish I had some good pics to show. Over the bedrooms the trusses are intact, can I leave them be? The living room has the cut truss chords, so there is no ceiling joist, just 2x8 rafters nailed to the original 2x4 truss rafters creating a vaulted ceiling over the Living Room. On the opposite side of the living room,(behind it) the truss chords of the bath and kitchen are secured to a beam creating the normal 8' ceiling.

Jim Luttrall
06-27-2007, 03:07 PM
Thanks Jim, I wish I had some good pics to show. Over the bedrooms the trusses are intact, can I leave them be? The living room has the cut truss chords, so there is no ceiling joist, just 2x8 rafters nailed to the original 2x4 truss rafters creating a vaulted ceiling over the Living Room. On the opposite side of the living room,(behind it) the truss chords of the bath and kitchen are secured to a beam creating the normal 8' ceiling.

If NONE of the truss is cut over the bedroom, then they should be good to leave in place. Even the braces inside the truss are very important to the strength of the truss. Some of the pictures seem to show an enlarged area above normal ceiling height (the one with the window). If any of the cross bracing that is part of the original engineered truss is cut, a substantial amount of strength is lost. I think it would be well worth the investment to hire an engineer or at least an EXPERIENCED contractor to design a repair. One good wind with the snow load and you could loose the whole cabin and maybe someone's life when the wall spread and the roof collapses.

Mike Truss Guy
02-10-2009, 12:15 AM
Thanks Jim, I wish I had some good pics to show. Over the bedrooms the trusses are intact, can I leave them be? The living room has the cut truss chords, so there is no ceiling joist, just 2x8 rafters nailed to the original 2x4 truss rafters creating a vaulted ceiling over the Living Room. On the opposite side of the living room,(behind it) the truss chords of the bath and kitchen are secured to a beam creating the normal 8' ceiling.

First I have two questions about the photos.

Do you think cardboard is really a wise choice for the ceiling? Ever hear the term fire-trap? There's a bare light bulb inches from that cardboard. ;)

Is that TV ready for DTV? ;)

Seriously though, if the trusses are cut, the spans are quite short, you could probably look up the correct rafter sizes in the code and conventional frame part of the cabin. Not the sleeping loft on the trusses is also an issue. Trusses are generally not designed for living space or storage in the attic space. As a rule, trusses shoudl never be modified without an engineer's seal. they are an engineered product. Unless you have the software to design them, you need to go to an engineer.