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First try at Sajjad Alt Vignette (Please Comment)

PostPosted: Wed Jan 29, 2014 11:51 am
by pman555
OK so I took my first shot at Sajjad's Alt Vignette today at lunch. All-in-all, it took me about 30 minutes. I'm testing Saturday.
Please let me know how I did.
The Program is pasted below.

Here is how I got the B.O. Joist heights:

Sajjad's Office (Assumed this was meeting room per Program)
Ceiling Height of 26'-6" + 8" lights + 12" Duct space = B.O. Joists @ 28'-2"
(Vignette CAD file states 48" deep joists in this space, but there's no option for that in the NCARB Software, so I drew 36" joists and added an extra 12" clear space below my joists)

1st Floor
Highest Ceiling Height 9'-6" + 8" lights + 24" Duct space = B.O. Joists @ 12'-2"

2nd Floor
Ceiling Height of 10'-0" + 8" lights + 24" Duct space = B.O. Joist @ 12'-8"



PROGRAM:

BUILDING SECTION VIGNETTE
SUGGESTED TIME: 1 HOUR

Famous Forum members want to stay close to each other and obtained a building where al of them can have their offices. On the work screen, locate a grade line and draw a schematic building section corresponding to a section cut line S-S. Your section should include all required sectional components and should reflect accurately the dimensions, structural relations and spatial relations indicated in the program and the plans. Vertical clearances not explicitly stated in the program or vignette directions must be accurately interpreted and indicated on your solution.

PROGRAM
The structural system consist of top chord bearing steel joists on masonry bearing walls with continuous concrete spread footings and concrete slab on grade.
1. All ceilings and roofs are flat.
2. Non-bearing corridor and Lobby walls must have a one-hour (minimum) fire-resistive rating.
3. Exterior and bearing walls have a 2-hour (min) fire resistance rating.
4. Ceiling heights:
First floor Lobby and corridors: 9'-0''; remaining floor: 9' - 6''.
Second floor: 10'-0'' throughout.
Meeting Room: 26'-6''.
5. Ceiling spaces must be used as return air plenums.
6. Provide 8” of clearance between the bottom of the ducts and finished ceiling to accommodate light fixtures and the
7. All ducts must be placed below the joists.
8. Parapets must extend 3'-6'' above the surface of decks at roof edges and at changes in the roof deck elevation.
9. The frost depth is 5'-0'' below grade.

Re: First try at Sajjad Alt Vignette (Please Comment)

PostPosted: Wed Jan 29, 2014 1:44 pm
by markarch
Looks good so far. In fact, I just did that one this morning :-)

quick question.. how did you figure the 24" duct spaces for the first and second floor rooms?
I got 16" duct spaces because there weren't any bigger ducts in that duct+joist combination "field of influence", as the joists that the section cuts through stop at the bearing wall (I assume the wall that shares the elevator shaft is a bearing wall, but open to correction/guidance). So I ignored the ducts North of that wall since, to me, it is an irrelevant joist+combo area that isn't shown in the section.

Re: First try at Sajjad Alt Vignette (Please Comment)

PostPosted: Wed Jan 29, 2014 1:54 pm
by pman555
markarch wrote:Looks good so far. In fact, I just did that one this morning :-)

quick question.. how did you figure the 24" duct spaces for the first and second floor rooms?
I got 16" duct spaces because there weren't any bigger ducts in that duct+joist combination "field of influence", as the joists that the section cuts through stop at the bearing wall (I assume the wall that shares the elevator shaft is a bearing wall, but open to correction/guidance). So I ignored the ducts North of that wall since, to me, it is an irrelevant joist+combo area that isn't shown in the section.


Thanks for the feedback.
You might be right with the 16" ducts. I looked at the tallest duct on the floor.
I'd love to hear from someone who knows for sure!

Re: First try at Sajjad Alt Vignette (Please Comment)

PostPosted: Wed Jan 29, 2014 2:17 pm
by markarch
This Alt has driven me nuts. I even opened it in AutoCAD to see what Sajjad's intentions were. He did break the joists at that (alleged) bearing wall. And even though the joist systems on both sides of that wall are the same depth and spacing, I still believe they should be considered independent. The beam is also an indicator of the separation of two different joist structure systems, at least that's my take on this particular Alt. But then, we got those two 8x8 running through my alleged bearing wall.. so that makes me wonder. :?

Re: First try at Sajjad Alt Vignette (Please Comment)

PostPosted: Thu Jan 30, 2014 6:30 am
by pman555
Does anyone else have any comments?

Re: First try at Sajjad Alt Vignette (Please Comment)

PostPosted: Fri Jan 31, 2014 6:24 am
by pman555
I'm testing tomorrow and would really appreciate some feedback on the vignettes in the original post.
I guess my/our biggest concern was whether I needed 24" duct clearance or only 16" as stated in previous posts by markarch.
Thanks!

Re: First try at Sajjad Alt Vignette (Please Comment)

PostPosted: Fri Jan 31, 2014 2:00 pm
by Coach
It's hard to read but appears that the largest first floor combination is 28" joist over 24" duct.

Re: First try at Sajjad Alt Vignette (Please Comment)

PostPosted: Sat Feb 01, 2014 9:49 am
by pman555
Coach wrote:It's hard to read but appears that the largest first floor combination is 28" joist over 24" duct.


Thanks for your response yesterday.
I sure hope you were right because I had a very similar situation on my exam today!

Re: First try at Sajjad Alt Vignette (Please Comment)

PostPosted: Sat Feb 01, 2014 4:20 pm
by ryukyo
Coach wrote:It's hard to read but appears that the largest first floor combination is 28" joist over 24" duct.


That is also the combination that I found.

Re: First try at Sajjad Alt Vignette (Please Comment)

PostPosted: Wed Nov 01, 2017 7:26 pm
by Pjandre
I know I am super late for the above people. But for anyone else. I did the same thing. I used the 24+28 combo on the first floor.

On the second floor, however, I used the 48" joists+12" duct combo. Anyone agree or disagree with this?

Also, Being that the computer doesn't allow for 48" joists in the software for Sajjad's office, I used the next largest size.

Any comment would be really appreciated! Thanks!

Re: First try at Sajjad Alt Vignette (Please Comment)

PostPosted: Thu Dec 07, 2017 7:25 pm
by hangryarch
Pjandre wrote:I know I am super late for the above people. But for anyone else. I did the same thing. I used the 24+28 combo on the first floor.

On the second floor, however, I used the 48" joists+12" duct combo. Anyone agree or disagree with this?

Also, Being that the computer doesn't allow for 48" joists in the software for Sajjad's office, I used the next largest size.

Any comment would be really appreciated! Thanks!



Hi,

I've honestly only looked at the images posted on here but I don't think you would use the 48" joists. Those only run in the double height space (sajjad's office) and I believe that would be treated as it's own entity. I believe the duct/joist combo for the second floor is 20" Joist depth and 24" max duct depth. So a total plenum depth of 44". Add 8" to that and I think you should have a 52" depth.

I could be wrong, but if anyone else can verify this that would be awesome