wood
A load-bearing frame composed of wooden beams, sheets, or other framing elements.
A wooden framework utilizes wood beams and sometimes sheets of wood to carry a structure's load and to resist lateral forces. Wood structures can rest on foundations of any other material.
This material is most common for small structures, but is also used frequently in roller coasters and medium-sized bridges.
The wood members contribute to carrying loads and resisting lateral movement. A foundation made from another material does not change the wooden framework above it into a different material.