Tools for finding wind loads in the State of Montana
Three main tools are used to find wind loads in the State of Montana.
- The ASCE 7 Hazard Tool website is an excellent resource. https://asce7hazardtool.online/
The user can log in as a guest and input an address, latitude/longitude, or pin the location on the site map. Additionally the user must select ASCE/SEI 7-16, a building risk category, and wind for the wind load type.
- The ATC hazards by location website is also useful and consistent with the ASCE 7 Hazard Tool website. https://hazards.atcouncil.org/
The user can look up wind loads by inputting the address, latitude/longitude, or pin the location on the site map. The user does not have to select a building type or version of ASCE 7 because the wind load for all building risk types for ASCE 7-16, 7-10, and 7-05 are all displayed.
- The final tool would be the wind load figures in the IBC. IBC Figure 1609.3(1), 1609.3(2), 1609.3(3), and 1609.3(4). https://codes.iccsafe.org/content/IBC2018P4/chapter-16-structural-design#IBC2018P4_Ch16_Sec1609
These figures are not easy to read or interpolate, so the first two websites are preferred.
The IBC has identified some areas in Montana as special wind regions. The Building and Commercial Measurements Bureau has not received any data from case studies of these regions and as such requires the minimum wind loads to abide by loads as if the region was not identified as a special wind region.
For areas not listed, or other questions regarding calculation of wind loads should be determined by calling the State Building Codes Bureau at 406-841-2056.
