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Section 5 Applying Technology: Producing Products and Structures
Walls
The wall frames are placed on top of
the floor. These frames support both exte-
rior and interior walls. Wall framing is
often made of 2 × 4 or 2 × 6 construction-
grade lumber. See Figure 17-14. A framed
wall has a strip at the bottom called the sole
plate. Nailed to the sole plate are uprights
called studs. The length of the studs is set
by how high the ceilings will be. At the top
of the wall, the studs are nailed to double
ribbons of 2 × 4s called a top plate or wall
plate. Door and window openings require
headers above them. Headers carry the
weight from the roof and ceiling across the
door and window openings. Shorter studs
called trimmer studs hold up the headers.
Ceilings and roofs
The walls support the ceiling and roof.
See Figure 17-15. The ceiling is the inside
surface at the top of a room. The roof is the
top of the structure that protects the house
from the weather.
Ceiling joists support the ceiling.
These joists rest on the outside walls and
some interior walls. Interior walls that help
support the weight of the ceiling and roof
are called load-bearing walls or bearing walls.
The roof forms the top of the build-
ing. There are many types of roofs, includ-
ing gable, flat, hip, gambrel, and shed.
Figure 17-13. The floors in single-family
homes are either concrete slabs or lumber.
Figure 17-14. Many of the parts of a wood-framed wall.
Subfloor
Floor
joist
Sill
Foundation
Lumber
Floor
Slab
Floor
Doubled top plate Trimmer stud
Header
Window
opening
Door
opening
Trimmer
stud
Stud
Sole
plate
Cripple stud