guyod

Hi

I am a contractor experienced in standard framing. I have a framing idea that is not standard. I am planning on making an addition to my living room. It will be a reverse A frame cathedral 16' wide 12' deep. The whole 16' will be open into the house with a post off center at 4'. I want it to be as open as possible. I have an idea to move the header up higher. Cut off the over hang on the trusses and attach the beam at the cut off with floor joists hangers. It is fairly large common trusses 35' span. I dont see why it wouldn't work but i have not seen it done so i wanted a 2nd opinion. The only issue i can see is that the corners of the beam will be sticking above the of the addition roof at the ends. Depending on how much of the corner sticks up i may have to drop the beam a little. Is there guide lines on how much of the corner can be cut off? The beam will most likely be on the outside of the existing house supported by the addition foundation.

Does any one see any other issues with this?

Thanks

nealtw

When adjusting trusses, our inspecters would send you off for an engineers report.
Cutting the top of the beam would likely not be allowed. The truss company could check your trusses and supply proper hangers and maybe engineer the beam. Or have them build a gerder truss instead of a beam, it could have tapered ends.
You are likely going to hand frame your roof, I would have them build the valley set to go over the original trusses, they are so easy.

guyod

Thanks
I dont see how cutting off the overhang of a truss is structually adjusting it but i have heard inspectors say crazier things. I did some more research and found out that simpson makes a special truss hanger. It is shorter but very heavy duty. 10 nails on each side into the beam.

I also found a guideline on how much you can cut off the top corner of a beam. I was suprised how much can be removed. half the height tappered to 3 times the height.

I was going to hand frame the roof its fairly small roof but it may be better it just to get scissor trusses. The ridge beam would add more weight to the header beam and the front will be all windows with quad doors so that would mean more heavy duty headers.

As long as i can order the valley set right it would be alot quicker. if im ordering the trusses it should be easier.

nealtw

Your trusses are designed to sit on a 3 1/2" or a 5 1/2" wall and a truss company will supply different hangers depending on truss design and the loads on them. Usually a girder truss will be cheaper than a beam. It's fine to find where you can cut the beam but an engineers report would still be required. With a sisser truss, they could raise the heal cut to hide the beam, which may be required to maintain the same gutter line with a lower pitch roof.

BridgeMan

Before getting too far into such a project, you would do well talking with the AHJ people to see what they will require. And most will require stamped documents from a registered P.E. before giving anything of this nature (not the norm) their blessing.