House Framing Materials

Dimensional Lumber and Conventional Framing

• Standard-size, milled lumber, called "dimensional lumber," is the most common house-framing material. Carpenters use dimensional lumber to construct homes using conventional, stick-frame construction. Many homeowners are familiar with the primary building unit of stick-frame construction, called a "stud-wall." Standard stud-walls consist of 2-by-4 lumber, which measures roughly 1 1/2-by-3 1/2 inches. To construct a basic stud-wall, carpenters fasten vertical framing members, called studs, between horizontal members, called plates.

Advanced Framing

• The term advanced framing refers to stick-frame structures that stray from conventional 2-by-4 stud-walls. In advanced framing, carpenters use large dimensional lumber and wide spacing. While conventional stick-frame walls consist of 2-by-4 lumber spaced every 16 inches, advanced framing might consist of 2-by-6 lumber spaced every 24 inches or a combination of 2-by-4 and wider lumber. Wider spacing and larger lumber decreases labor requirements and increases the amount of wall cavity space for insulation materials.

Steel

• Steel framing systems resemble conventional stick-frame construction. For residential projects, steel framing resembles the familiar stud wall. Builders attach upright steel framing members, called studs, to horizontal framing members, called tracks. Steel framing materials are lightweight, strong and always consistent in size. Unlike wood framing materials, steel framing resists moisture damage, pest infestation and warping. However, steel framing materials are generally more expensive than wood framing materials.

Masonry

• Builders use precast blocks, called concrete masonry units, and concrete forms to construct homes. Concrete masonry units, or CMU, stack in neat, staggered rows to form thick, sturdy walls. Builders usually fill the hollow cavities of block walls with reinforcing steel and concrete. Alternatively, builders construct homes from solid concrete or insulated concrete forms (ICF), which resemble large building blocks. The walls of ICF units usually consist of a cement and foam mixture. Builders stack ICF units and fill the cavities with rebar and cement.

Alternative Construction Methods

• Favorite alternative construction methods use natural materials to frame a home's structure. Alternative construction methods include straw bale construction and cob. To construct walls of straw bales, builders usually sandwich full-size bales of straw between thin stud-walls. The term "cob" refers to a mixture of sand, soils and straw. Builders form cob into bricks or entire wall units. Although relatively well established, alternative construction methods are not recognized by many building authorities.