I rarely dabble with the prescriptive code sections for foundation design. At first glance, I noticed the 2021 IRC does not have any prescriptive approach for the design of uplift on foundations. However, the Florida Building Code, Residential does. Is anyone familiar with why this limitation exists with the IRC.
For those familiar with the 2020 FBC, Residential, how have you found the prescriptive foundations sections to perform? I realize the tables are limiting for wind and don't allow you to go higher than 150 MPH or anywhere near the HVHZ for that matter.
Also, the prescriptive tables provide gravity and uplift (which is negligible in their eyes for any CMU wall construction). However, I don't see any discussion about out-of-plane lateral loads and the need to resolve the overturning of individual wall segments. With leeward winds, and uplift, there are a lot of rotations happening on an eccentric footing and manual calculations have always resulted in foundations that are ridiculous in comparison to concentric stem wall foundations.
For those familiar with the 2020 FBC, Residential, how have you found the prescriptive foundations sections to perform? I realize the tables are limiting for wind and don't allow you to go higher than 150 MPH or anywhere near the HVHZ for that matter.
Also, the prescriptive tables provide gravity and uplift (which is negligible in their eyes for any CMU wall construction). However, I don't see any discussion about out-of-plane lateral loads and the need to resolve the overturning of individual wall segments. With leeward winds, and uplift, there are a lot of rotations happening on an eccentric footing and manual calculations have always resulted in foundations that are ridiculous in comparison to concentric stem wall foundations.