Background Building codes require that buildings be classified by their level of importance in determining the risk taken with safety factors against their failure under critical design loads. Calculations for the structure’s overall stability, flexure, and fatigue are all based on the assumption of a given risk category design level. ASCE 7 references risk category…
In terms of determining the risk category to a building component mounted to a building, the component ‘inherits’ the design properties of the structure. So a sign attached to a risk category II structure would be risk category II. If the sign is freestanding and not part of a main structure, while matching the…
The Applied Technology Council (ATC) offers site-specific information that is used in our calculators to determine the wind velocity. For the best results, the address of the site may be used. To find your wind speed, follow the step-by-step guide below. Navigate to https://hazards.atcouncil.org/#/ Enter your address, zip code, or city and state in the search…
Many who don’t understand how wind works will state a product is rated to a specific wind velocity which is false advertising and not true. “Rated to 180 MPH wind” is frequently seen in marketing materials which is a false and misleading statement that comes with many unwritten disclaimers. The formula that converts wind velocity to…
ASCE 7 separates wind loading into three types: Main Wind Force Resisting System (MWFRS), Components and Cladding (C&C), and Other Structures and Building Appurtenances. MWFRS is defined as “(a)n assemblage of structural elements to provide support and stability for the overall structure.” Typically, members which receive loading from two surfaces are designed to resist MWFRS…
From the 5th Edition of the Florida Building Code (2014) section 1603.1.4 and from section 1603.1.4. of the 2012 International Building Code, construction documents shall show the following: Ultimate design wind speed, Vult (3-second gust), miles per hour and nominal design wind speed (Vasd) as determined in accordance with code section 1609.3.1 Risk Category…
First, it needs to be said that there is a complicated formula that converts wind velocity to wind pressure. Many wind pressure values can exist from a single wind velocity which vary based on roof height, topography, terrain, even code version, and more. See our wind speed to wind pressure calculators for different ASCE codes by…