Can anyone provide insight on when you can consider a building as fully exposed? The terrain/parapet conditions are pretty straightforward but the mechanical equipment note is pretty vague. Typically I would just consider a building as partially exposed but I'm currently looking at an existing structure and would love to sharpen my pencil and use Ce = 0.9 when calculating flat roof snow load. It meets requirements for terrain and parapet but does have some mechanical equipment.
As per ASCE7:
Partially Exposed: All roofs except as indicated in the following text. Fully Exposed: Roofs exposed on all sides with no shelter
afforded by terrain, higher structures, or trees. Roofs that contain several large pieces of mechanical equipment, parapets that extend above the
height of the balanced snow load, or other obstructions are not in this category. Sheltered: Roofs located tight in among conifers that qualify
as obstructions.
As per ASCE7:
Partially Exposed: All roofs except as indicated in the following text. Fully Exposed: Roofs exposed on all sides with no shelter
afforded by terrain, higher structures, or trees. Roofs that contain several large pieces of mechanical equipment, parapets that extend above the
height of the balanced snow load, or other obstructions are not in this category. Sheltered: Roofs located tight in among conifers that qualify
as obstructions.