Wood construction can economically provide a well-performing structural system for seismic behavior. Seismic forces are the result of inertial mass, so lightweight structural materials such as wood framing develop lower seismic loads from their own weight than heavier structural materials. Wood-framed wood structural panel shear wall lateral systems also behave in a preferable ductile manner. In non-technical terms, they bend and move under seismic loads instead of being rigid and breaking in a brittle fashion. Technically, this results in a high seismic response modification coefficient factor, R, of 6.5.