ASCE Risk Categories Explained

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…

Wind Speed vs. Wind Pressure Explained

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 Main Wind Force vs. Components & Cladding Explained (MWFRS vs. C&C)

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…

The Recently Updated Saffir-Simpson Scale

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…