No idea how the trusses are going to look like
No idea how the trusses are going to look like
(OP)
Ok, so I have this big residential duplex project. The shape of the roof is so complicated with bunch of dormers facing on all sides. The owner/contractor said that the roof is going to be trusses. I have no idea how the trusses are going to be laid. How will I be able to design this? Kinda hard to design the house if you dont know where the girder trusses are going to be. In so areas, I dont even know which direction the truss is going to run. Shall I insist the owner to give the drawings to the truss manufacturer first? Then they can give me the shop drawings then I can design the rest of the house. The owner wants to get his permit asap and then contact the truss manuf. I think it should be the other way around. I am so confused because top of the windows at the dormers are higher than the top plates of the upperfloor walls. Any input?





RE: No idea how the trusses are going to look like
Only way you can design the building...
Windows thru the top plate... That might be a problem using them as chords for the roof diaphragm..
Good luck
RE: No idea how the trusses are going to look like
Are the dormers "active" or are they "false". If they are active, you will need girder trusses on either side of the dormer. If not, they can build the dormer walls directly on top of the roof.
RE: No idea how the trusses are going to look like
I would make telling the owner you have no idea my absolute last resort. That just makes you look bad. Now I'm not saying to do something you are not qualified to do, but you should have put on your thinking cap and exhausted your intellect before telling the client you don't have a clue.
If you have problems with framing the trusses because of high windows, dormers or other fun things, remember that you can add a bearing wall(s) if necessary and turn the framing another direction, add girders, beams, whatever you need to make it work. All that requires coordination with the architect or owner but that's what we do. If necessary you may also have to stick-frame a portion, but I would avoid that also if possible. Since you've budgetted for trusses, you may not have time left in the budget for additional work due to designing roof framing.
RE: No idea how the trusses are going to look like
I would then talk to the architect about the local dormer details e.t.c. and explain the consequences and try to get them to agree to a simpler detail.
It is always best to try and talk the architect out of difficult details in the beginning of a project (politically: "suggestions for economy") than to try and talk them out of it whan they have already fully detailed it.
RE: No idea how the trusses are going to look like
RE: No idea how the trusses are going to look like
RE: No idea how the trusses are going to look like
http://www.usagani.com/other/ROOF.jpg
RE: No idea how the trusses are going to look like
Can you give a hint about the scale? and can you indicate which windows go above the top plate?
The TPIC recommends engineered involvement in the installation for trusses in excess of 60' and some local codes use 40'. TPIC also recommends engineering involvement for trusses that are piggybacked due to the height. Lateral bracing for this would also be an issue.
RE: No idea how the trusses are going to look like
RE: No idea how the trusses are going to look like
Dik
RE: No idea how the trusses are going to look like
If you are planning on buying the truss from a wood or light gauge manufacturer, LET THEM DO THE DESIGN.
Most truss manufacturers would be happy to help you with your prelim dwgs - I know my company would. They know the limitations of their product and they know how things are typically done.
Why bang your head against a wall, and end up with something the truss manuf. will likely change anyway? If there are bearing issues, like at your dormers, let them tip you off right away!
You won't look "stupid" asking for help, but you will when trusses arrive onsite that don't work if you do the design yourself.
Engineering is knowing how to find answers to your problems - not necessarily coming up with all the answers yourself.
RE: No idea how the trusses are going to look like
Dik
RE: No idea how the trusses are going to look like
RE: No idea how the trusses are going to look like
RE: No idea how the trusses are going to look like
"Engineering is knowing how to find answers to your problems - not necessarily coming up with all the answers yourself."
I know this is an old thread. I hope you got it all figured out.