Page 5
Introduction
Methods for constructing walls for buildings. Walls are constructed in
different forms and of various materials to serve several functions.
Exterior walls protect the building interior from external environmental
effects such as heat and cold, sunlight, ultraviolet radiation, rain and
snow, and sound, while containing desirable interior environmental
conditions. Walls are also designed to provide resistance to passage of
fire for some defined period of time, such as a one-hour wall. Walls often
contain doors and windows, which provide for controlled passage of
environmental factors and people through the wall line.
Walls are designed to be strong enough to safely resist the horizontal and
vertical forces imposed upon them, as defined by building codes. Such
loads include wind forces, self-weight, possibly the weights of walls and
floors from above, the effects of expansion and contraction as generated
by temperature and humidity variations as well as by certain impacts, and
the wear and tear of interior occupancy. See Loads, dynamic, Loads,
transverse Modern building walls may be designed to serve as either
bearing walls or curtain walls or as a combination of both in response to
the design requirements of the building as a whole. Both types may
appear similar when complete, but their sequence of construction is
usually different.
Bearing-wall construction may be masonry, cast-in-place or precast
reinforced concrete, studs and sheathing, and composite types. The design
loads in bearing walls are the vertical loading from above, plus horizontal
loads, both perpendicular and parallel to the wall plane. Bearing walls
must be erected before supported building components above can be
erected.
Curtain-wall construction takes several forms, including lighter versions
of those used for bearing walls. These walls can also comprise assemblies
of corrugated metal sheets, glass panels, or ceramic-coated metal panels,
each laterally supported by light subframing members. The curtain wall
can be erected after the building frame is completed, since it receives
vertical support by spandrel beams, or relieving angles, at the wall
line.Masonry walls are a traditional, common, and durable form of wall
construction used in both bearing and curtain walls. They are designed in