Wood Construction

Intrudction of light framing

Intrudction of light framing

Light framing is the use of closely spaced members of dimension lumber size combined with sheathing to form structural elements of a building. The structural elements provide rigidity, support for interior finish and exterior cladding, and a cavity for the installation of insulation.

Light framing is the most common method of residential construction in North America. It is also a form of construction which can be used on a larger scale for commercial and public buildings. For example, the Forintek Canada Corp. forest products research facility in Vancouver, Canada, a 9300 m2 (100,000 sq. ft.) building, uses light frame construction on a large scale to house offices and laboratories.

Where a typical wall in a residence might be a 38 x 89mm (2" x 4" nom.) extending 2.4m (8'), the walls in the Forintek building are built of 38 x 235mm (2" x 10" nom.) studs which extend 5m (16') from floor to ceiling. The result is a solid building meeting the exacting requirements for a research facility.

Light framing makes use of dimension lumber (generally sawn lumber 38mm (2" nom.) wide and up to 286mm (12" nom.) deep) and manufactured wood products of comparable size to build structural frameworks. These main structural members are used in concert with sheathing elements to provide rigidity for walls, floors, and roofs. Typically, light frame members are spaced no further apart than 600mm (2').

Intrudction of light framing 02

Figure 1 demonstrates a typical arrangement of framed members.

For some loading configurations, engineered wood products such as light frame trusses, prefabricated wood I'joists, or other structural products such as laminated veneer lumber (LVL), parallel strand lumber (PSL) and glulam may be used as framing elements. Where large or clear spans are a requirement, light framing members may be used in combination with heavy beams or columns to transfer loads directly to foundations.

Frame construction, by using small repetitive members and fasteners, develops a redundancy of design. This means that alternate paths of load transmittal become available when the primary path fails. For this reason, frame construction is not prone to sudden failure and is recognized as a good construction technique for resisting, for example seismic and wind forces.