All elements of a raised wood floor system must be properly sized and assembled to support the design loads.
A continuous load path must be provided to transfer lateral and vertical loads from the roof, walls, and floor system to the foundation.
A load path can be thought of as a “chain” running through the building. Because all applied loads must be transferred to the ground, the load path chain must connect to the foundation.
- To be effective, each link in the chain must be strong enough to transfer load without breaking.
- Suitable uplift, lateral, and shear connections are also required to complete the load path.
- A strong continuous load path is especially important in areas subject to high winds and/or seismic forces.
Wind and Seismic Considerations
Construction in areas subject to high-wind and earthquake forces can pose unique problems to the designer and builder.
The American Wood Council’s Wood Frame Construction Manual for One- and Two-Family Dwellings (WFCM; www.awc.org) provides engineered and prescriptive design requirements for wood-frame construction in areas subject to 110-195 mph wind speeds (3-second gusts) and seismic design categories A-D. This manual is referenced in the 2015 International Building Code and the 2015 International Residential Code. In regions where wind speeds equal or exceed 110 miles per hour, raised wood floor systems should be designed and constructed in accordance with the WFCM.