Softwood plywood is a common building material for roofs, walls and floors.
Softwood comes from various species of evergreen conifers including
spruce, pine and fir. Plywood made from softwood is a building product
commonly found in home construction and is also used for other purposes.
Softwood plywood is available in different grades for various
applications. The finish on softwood plywood ranges from fully sanded to
not sanded at all, depending on the intended use.
Exterior Home Sheathing
The most common wall construction on a new home consists of a 2-by-4 or
2-by-6 frame covered by exterior-grade sheathing. This type of wall
forms a structural panel that performs well at high wind loads and
during earthquakes. Plywood panels fastened to each stud and to the top
and bottom plates of the wall frame strengthen it and resist vertical,
horizontal and diagonal shifting. Strict adherence to building codes for
fastener placement, distance between studs and the joints between
panels ensure strong, solid walls.
Home Roofing and Flooring
Plywood for building construction has a span rating that governs how it
is used to build subfloors and to sheath roofs. On floors, the plywood
panels have tongue-and-groove edges that fit together. On a roof, the
plywood carries less load and the tongue-and-groove edges are not
required. The manufacturer-assigned span rating for roofs and floors
specifies the maximum allowed distance between rafters for a roof and
between joists for a floor.
Other Construction
Softwood plywood has other applications in home building in addition to
roofs, walls and floors. Eaves and soffits are often covered with
plywood. Some plywood is manufactured specifically as a siding product,
most notably T-111 siding, a grooved sheet product made to appear
similar to reverse board and batten siding. Builders also use plywood
for building detached garages and sheds, temporary flooring and concrete
forms. Plywood is also used for many of the same purposes in commercial
building construction.
General Projects
Softwood plywood has many uses beyond building homes and is used for a
wide range of projects from skateboard ramps to doghouses. In the
workshop, softwood plywood covers work tables and is used to build
sawhorses and general-purpose shelving. It is inexpensive, available in a
wide range of thicknesses and grades, ranging from exterior with
exposure to the elements to interior dry areas.