The ultimate design wind speed, Vult, in mph, for the determination of the wind loads shall be determined by Figures 1609.3(1), 1609.3(2) and 1609.3(3). The ultimate design wind speed, Vult, for use in the design of Risk Category II buildings and structures shall be obtained from Figure 1609.3(1). The ultimate design wind speed, Vult, for use in the design of Risk Category III and IV buildings and structures shall be obtained from Figure 1609.3(2). The ultimate design wind speed, Vult, for use in the design of Risk Category I buildings and structures shall be obtained from Figure 1609.3(3). The ultimate design wind speed, Vult, for the special wind regions indicated near mountainous terrain and near gorges shall be in accordance with local jurisdiction requirements. The ultimate design wind speeds, Vult, determined by the local jurisdiction shall be in accordance with Section 26.5.1 of ASCE 7.
In nonhurricane-prone regions, when the ultimate design wind speed, Vult, is estimated from regional climatic data, the ultimate design wind speed, Vult, shall be determined in accordance with Section 26.5.3 of ASCE 7.
FIGURE 1609.3(1) ULTIMATE DESIGN WIND SPEEDS, vult, FOR RISK CATEGORY II BUILDINGS AND OTHER STRUCTURES
FIGURE 1609.3(2) ULTIMATE DESIGN WIND SPEEDS, vult, FOR RISK CATEGORY III AND IV BUILDINGS AND OTHER STRUCTURES
FIGURE 1609.3(3) ULTIMATE DESIGN WIND SPEEDS, vult, FOR RISK CATEGORY I BUILDINGS AND OTHER STRUCTURES
In nonhurricane-prone regions, when the ultimate design wind speed, Vult, is estimated from regional climatic data, the ultimate design wind speed, Vult, shall be determined in accordance with Section 26.5.3 of ASCE 7.
FIGURE 1609.3(1) ULTIMATE DESIGN WIND SPEEDS, vult, FOR RISK CATEGORY II BUILDINGS AND OTHER STRUCTURES
FIGURE 1609.3(2) ULTIMATE DESIGN WIND SPEEDS, vult, FOR RISK CATEGORY III AND IV BUILDINGS AND OTHER STRUCTURES
FIGURE 1609.3(3) ULTIMATE DESIGN WIND SPEEDS, vult, FOR RISK CATEGORY I BUILDINGS AND OTHER STRUCTURES
When required, the ultimate design wind speeds of Figures 1609.3(1), 1609.3(2) and 1609.3(3) shall be converted to nominal design wind speeds, Vasd, using Table 1609.3.1 or Equation 16-33.
where:
TABLE 1609.3.1 WIND SPEED CONVERSIONSa, b, c
where:
| Vasd | = | Nominal design wind speed applicable to methods specified in Exceptions 4 and 5 of Section 1609.1.1. |
| Vult | = | Ultimate design wind speeds determined from Figures 1609.3(1), 1609.3(2) or 1609.3(3). |
TABLE 1609.3.1 WIND SPEED CONVERSIONSa, b, c
| Vult | 100 | 110 | 120 | 130 | 140 | 150 | 160 | 170 | 180 | 190 | 200 |
| Vasd | 78 | 85 | 93 | 101 | 108 | 116 | 124 | 132 | 139 | 147 | 155 |
| For SI: 1 mile per hour = 0.44 m/s. |
| a. Linear interpolation is permitted. |
| b. Vasd = nominal design wind speed applicable to methods specified in Exceptions 1 through 5 of Section 1609.1.1. |
| c. Vult = ultimate design wind speeds determined from Figure 1609.3(1), 1609.3(2) or 1609.3(3). |