Understanding Truss Drawing

[rrthor50]

This is my first post to the group. Thanks in advance for your help. I am building a large garage with a living space above. It is 30 ft wide and 42 ft long with 15 ft high walls and an attic truss that will carry a living space with a living room, bathroom, bedroom and a small kitchenete.

My trusses have a 2x10 bottom chord and 2x8 top chords. They are 34 ft long and cant out over the 30 ft wide building providing an attic space that is 16 ft wide and 8 ft high. It is a 9/12 pitch.

When I talked to the truss company I told them what I wanted to do. The framing is now complete and when I am up in the attic space i am amazed that these trusses will carry the load of a full living space. Could I get some comments on the below truss specifications as to whether I have enough capacity in regards to loading for my application.

Loading
LL (25.0) + DL (7.0) on top chord = 32.0 psf
DL on bottom chord = 10 psf
Total Load = 42.0 psf

BC UNIF LL (40) + DL (10.0) = 50.0 psf 9' - 0.0" to 25' -0,0" V

I would post the drawing but I think I am unable to because of the fact that I am a new member.

Thanks
Rick

[Don_P]

Welcome to the forum :)

Live Load (snow) 25 pounds/square foot + Dead load (weight of roof materials) 7 psf= 32psf on "rafter" chord.

Dead load on bottom chord, self weight of "floor chord" 10 psf
Total load, 32psf+10psf=42 psf

Bottom chord uniformly distributed live load 40 psf+ 10 psf dead in the "room" area

Yup they are a nice truss. I've also had them gang them up on each side of a dormer opening and pop dormers out of each side of the roof for bed and bathrooms.

Your picture posting ability should be switched on.

[rrthor50]

Thanks so much for your reply Don. So to sum this up so I can put this to bed, I shouldn't have to worry that I will come crashing to the ground if there is a little snow on the roof and I am sitting in the bathtub full of water reading the latest edition of Popular Mechanics while the wife is in the kitchen baking cookies.

BTW as long as I have your ear would you floor this space with 3/4" TG plywood or 1 1/8"

I lived in Virginia in the 80's and will never forget the beautiful motorcycle rides through the Blue Ridge Mountains.

Thanks Again

Rick

[Don_P]

Gotta admit I'll never have much money here but I'm rich. Traffic was heavy on the way to work this morning, I had to slow down for a grouse and a deer.

I think you'll be all right up there. If it were mine it would get 3/4 advantech and 3/4" hardwood flooring. But we're getting into personal preference. I'd avoid tile in the bath if you can. Although the deflection numbers are probably low the span is pretty great, that is where stiffer ply might help, don't know.

[rrthor50]

Again ... Thanks

Rick