Wind coefficient
From ASHRAE, 1989
Shielding class | Description | Wind coefficient aw, |
Wind coefficient aw, |
||||
Number of stories |
Number of stories |
||||||
One |
Two |
Three |
One |
Two |
Three |
||
1 |
No obstructions or local shielding. | 0.000319 |
0.000420 |
0.000494 |
0.0119 |
0.0157 |
0.0184 |
2 |
Light local shielding; few obstructions, a few trees or small shed | 0.000246 |
0.000325 |
0.000382 |
0.0092 |
0.0121 |
0.0143 |
3 |
Moderate local shielding; some obstructions within two house heights, thick hedge, solid fence, or one neighboring house | 0.000174 |
0.000231 |
0.000271 |
0.0065 |
0.0086 |
0.0101 |
4 |
Heavy shielding; obstructions around most of perimeter, buildings or trees within 10 m in most directions; typical suburban shielding | 0.000104 |
0.000137 |
0.000161 |
0.0039 |
0.0051 |
0.0060 |
5 |
Very heavy shielding; large obstructions; typical downtown shielding | 0.000032 |
0.000042 |
0.000049 |
0.0012 |
0.0016 |
0.0018 |