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'Framing', in construction known as 'light frame construction', is a building technique based around structural members, usually called studs, which provide a stable frame to which interior and exterior wall coverings are attached, and covered by a roof comprising horizontal joists or sloping rafters covered by various sheathing materials. Modern light-frame structures usually gain strength from rigid panels used to form all or part of wall sections, but until recently carpenters employed various forms of diagonal bracing to stabilize walls. Diagonal bracing remains a vital interior part of many roof systems.
Light frame construction has become the dominant construction method in North America and Australia because of its economy. Use of minimal structural materials allows builders to enclose a large area with minimal cost, while achieving a wide variety of architectural styles. The ubiquitous platform framing and the older balloon framing are the two different light frame construction systems used in North America.

Contents

Walls

Corners

Exterior wall studs

Interior partitions

Lintels (headers)

Wall Sections

Balloon framing

Platform framing

Materials

Roofs

Structure

See also

References

Notes

External links

Walls

Wall framing in house construction includes the vertical and horizontal members of exterior walls and interior partitions. These members, referred to as studs, wall plates and lintels, serve as a nailing base for all covering material and support the upper floors, ceiling and roof. Framing lumber should be grade-stamped, and have a moisture content not exceeding 19%.
There are two methods of framing a house. Balloon framing was common until the late 1940s, but since that time, platform framing has become the predominant form of house construction.
This method of framing (platform framing) wall sections horizontally on the subfloor prior to erection is widely used. The top and bottom plates are end-nailed to each stud with two nails at least 3 1/4 in. (82 mm) in length. Studs are doubled at openings, the jack stud being cut to receive the lintels that are placed and end-nailed through the outer studs.
Framing lumber should be grade-stamped, and have a moisture content not exceeding 19%.
Wall sheathing is usually applied to the framing prior to erection, thus eliminating the need to scaffold. Some types of sheathing, such as asphalt-impregnated fibreboard, plywood, oriented strand board and waferboard, will provide adequate bracing to resist lateral loads and keep the wall square. Others, such as rigid glass-fibre, asphalt-coated fibreboard, polystyrene or polyurethane board, will not. In this latter case, the wall should be reinforced with a diagonal wood or metal bracing let into the studs.

Corners

A multiple-stud post made up of at least three studs, or the equivalent, is generally used at exterior corners and intersections to secure a good tie between adjoining walls and to provide nailing support for the interior finish and exterior sheathing. Corners and intersections, however, must be framed with at least two studs.
Nailing support for the edges of the ceiling finish is required at the junction of the wall and ceiling where partitions run parallel to the ceiling joists. ^[1]

Exterior wall studs

Wall framing in house construction includes the vertical and horizontal members of exterior walls and interior partitions. These members, referred to as studs, wall plates and lintels, serve as a nailing base for all covering material and support the upper floors, ceiling and roof.
Exterior wall studs are the vertical members to which the wall sheathing and cladding are attached. They are supported on a bottom plate or foundation sill and in turn support the top plate. Studs usually consist of 2 x 4 in. (38 x 89 mm) or 2 x 6 in. (38 x 140 mm) lumber and are commonly spaced at 16 in. (400 mm) on centre. This spacing may be changed to 12 in. (300 mm) or 24 in. (600 mm) on centre depending on the load and the limitations imposed by the type and thickness of the wall covering used. Wider 2 x 6 in. (38 x 140 mm) studs may be used to provide space for more insulation. Insulation beyond that which can be accommodated within a 3 1/2 in. (89 mm) stud space can also be provided by other means, such as rigid or semi-rigid insulation or batts between 2 x 2 in. (38 x 38 mm) horizontal furring strips, or rigid or semi-rigid insulation sheathing to the outside of the studs. The studs are attached to horizontal top and bottom wall plates of 2 in. (nominal) (38 mm) lumber that are the same width as the studs.

Interior partitions

Interior partitions supporting floor, ceiling or roof loads are called loadbearing walls; others are called non-loadbearing or simply partitions. Interior loadbearing walls are framed in the same way as exterior walls. Studs are usually 2 x 4 in. (38 x 89 mm) lumber spaced at 16 in. (400 mm) on centre. This spacing may be changed to 12 in. (300 mm) or 24 in. (600 mm) depending on the loads supported and the type and thickness of the wall finish used.
Partitions can be built with 2 x 3 in. (38 x 64 mm) or 2 x4 in. (38 x 89 mm) studs spaced at 16 or 24 in. (400 or 600 mm) on centre depending on the type and thickness of the wall finish used. Where a partition does not contain a swinging door, 2 x 4 in. (38 x 89 mm) studs at 16 in. (400 mm) on centre are sometimes used with the wide face of the stud parallel to the wall. This is usually done only for partitions enclosing clothes closets or cupboards to save space. Since there is no vertical load to be supported by partitions, single studs may be used at door openings. The top of the opening may be bridged with a single piece of 2 in. (nominal) (38 mm) lumber the same width as the studs. These members provide a nailing support for wall finish, door frames and trim.

Lintels (headers)

Lintels (aka headers) are the horizontal members placed over window, door and other openings to carry loads to the adjoining studs. Lintels are usually constructed of two pieces of 2 in. (nominal) (38 mm) lumber separated with spacers to the width of the studs and nailed together to form a single unit. The preferable spacer material is rigid insulation. The depth of a lintel is determined by the width of the opening and vertical loads supported.

Wall Sections

The complete wall sections are then raised and put in place, temporary braces added and the [bottom plates nailed through the subfloor to the floor framing members. The braces should have their larger dimension on the vertical and should permit adjustment of the vertical position of the wall.
Once the assembled sections are plumbed, they are nailed together at the corners and intersections. A strip of polyethylene is often placed between the interior walls and the exterior wall, and above the firsttop plate of