Structural window 1

[COEngineeer]

I have this residential house project where I have a non typical window. If you see the cross section, it goes from main level to top of 2nd floor then it cuves to the ridge beam. First I just drew it and put "Structural windor per manuf.". The city responded back that I need detail for it. So my question is, what type of X-section can I bend so I can use it as bent "king stud"? Can you bend rectangular tubing? Channels? The architect thinks the member should not be thicker than 5" wide(4 windows in a row). What do you think I should use? I guess once I design the structure I just put a note on the windows especially the one that curves on the top to make sure it can take the snow load.

 

[COEngineeer]

Also, if the snow load is 80 psf, what note shall I put on the window? Ask for 150 psf rated window or something? I am just a little worried since the top window will act like a roof.

 

[twinnell]

The detail the city is requesting, is it a window support detail? Does the widow have a radius or a bend where it goes from vertical to the roof pitch? You can have any piece of steel rolled to match the curvature of the window (if curved). I can see using typical king studs in the walls then add a curved steel member from the top of the wall (at eave) to ridge beam. Support the curved member on the top plate directly above the king studs and the ridge beam. Size king studs and ridge beam accordingly. Or if you want the materials in that load path to be alike, use hss sections for the jambs and the curved member.

 

[twinnell]

Add a note stating that the window manufacture shall design the window to resist the following additional loads at roof:
Dead Load =
Roof Live load =
Snow Load =
Net Wind Uplift Load=

 

[COEngineeer]

twinnel, to make the thickness of the jambs uniform, I think ill just use all steel. I wasnt sure if you can bend any steel members. Another question, standard 2 panes windows that you can find at most new housed, do you know what pressure those can handle? I assume it can take pretty high pressure due to high wind load right?

 

[twinnell]

I don't know the actual design pressure for the window, but you can calculate the design wind pressure for the window support members your are going to design. Use components and cladding wind pressure from ASCE 7.

Also, I would add a note stating that the window manufacture shall provide adequate attachement to the provided support.

 

[structuralaggie]

I've done several projects with rolled steel. One was a free standing staircase with an intermediate landing (supported by the stringers). The stringers were speced and designed as 8x6x1/4 rolled tubes, but they were actually built on site with 1/4 plates continuously welded at the edges in place of the tubes because of the difficulty in 3d bending of the tube.

A "bent" member as I call it is actually cut and welded to the the required shape. This will probably be much cheaper than rolling, if that is an option. The stringers had to be rolled because of aesthetic reasons.