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Challenge Question Number 1 for Architect #1139

Clearly describe what you expect from the students:
Project parameters:

Ceiling height above the first floor: 9’-0”

All ducts must run below second floor structure joists.

Provide 9” clearance for light fixtures between bottom of ducts and finish ceiling.

Second Floor Steel joists and slab depth: 2’-0”

Mechanical Duct dimensions: 18” round ducts

A. What is the minimum floor to floor height required to satisfy all of the structural, mechanical and electrical items?
B. The floor to floor heights have been set and cannot be changed. While you are finishing the drawings, the structural engineer has decided that the actual depth of the second floor joists must be 28 inches. The ducts cannot be reduced to less than 16” diameter and the light fixture clearance cannot be changed. What two changes to the project parameters can you propose to maintain the new structure depth and floor to floor heights?

In order to give the teacher some guidance in evaluating the student's project(s); list some tips that may help to assess the student's work:
Answer for Question A:
9’-0” Ceiling Height
0’-9” Light Fixture Clearance
2’-0” Structure Depth
+1’-6” Duct Depth
_______
=13’-3” Floor to Floor Height

Answer to Question B:
0’-9” Light Fixture Clearance
+ 2’-4” Structure Depth
_____
= 3-1” Fixed depth that cannot be changed

13-3” Fixed Floor to floor height
- 3’-1” Fixed depth above
_____
= 10’-2”
- 1-4” Minimum Duct diameter
_____
= 8’-10” New Ceiling Height

Duct needs to be reduced to 16” with ceiling height reduced to 8-10”
Or
Duct remains at 18” and ceiling height reduced to 8’-8”