Page 59 - 2018_IRC

BUILDING PLANNING

TABLE R301.2(3)
HEIGHT AND EXPOSURE ADJUSTMENT COEFFICIENTS FOR TABLE R301.2(2)
EXPOSURE
MEAN ROOF HEIGHT
B C D
15 1.00 1.21 1.47
20 1.00 1.29 1.55
25 1.00 1.35 1.61
30 1.00 1.40 1.66
35 1.05 1.45 1.70
40 1.09 1.49 1.74
45 1.12 1.53 1.78
50 1.16 1.56 1.81
55 1.19 1.59 1.84
60 1.22 1.62 1.87

For SI: °C = [(°F)-32]/1.8.
FIGURE R301.2(1)
1
ISOLINES OF THE 97 / -PERCENT WINTER (DECEMBER, JANUARY AND FEBRUARY) DESIGN TEMPERATURES (°F)
2
34 2018 INTERNATIONAL RESIDENTIAL CODE ®
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