Estimating in Building Construction

132 CHAPTERELEVEN

Lintels. Alintelis the horizontal member that supports the
masonry above a wall opening. In other words, it spans the
opening. Materials used for lintels include steel angle iron,
composite steel sections, lintel block (shaped like a U) with
reinforcing bars and filled with concrete, and precast concrete.
The lintels are usually set in place by masons as they lay up the
wall. Some specifications require that the lintel materials be
supplied under this section, whereas other specifications
require the steel angles and composite steel section to be sup-
plied under “structural steel” or “miscellaneous accessories.”
Precast lintels may be supplied under “concrete”; the lintel
block will probably be included under “masonry,” as will the
reinforcing bars and concrete used in conjunction with it.
It is not unusual for several types of lintels, in a variety
of sizes, to be required on any one project. They must be sep-
arated into the types, sizes, and lengths for each material
used. Steel lintels may require extra cutting on the job so that
the masonry will be able to fit around them. If a lintel is
heavy, it may be necessary to use equipment (such as a lift
truck or a crane) to put it in place. In determining length, be
certain to take the full masonry opening and add the
required lintel bearing on each end. Lintel bearing for steel is
generally a minimum of 4 inches, whereas lintel block and
precast lintels are often required to bear 8 inches on each
end. Steel is purchased by the pound, precast concrete by the
linear foot, and lintel block by the unit (note the width,

height, and length). Precast concrete lintels are covered in

Section 10–18.

Sills. Sillsare the members at the bottoms of window or

door openings. Materials used are brick, stone, tile, and pre-

cast concrete. These types of sills are installed by the mason,

although the precast concrete may be supplied under a dif-

ferent portion of the specifications. The brick and tile sills

are priced by the number of units required, and the stone

and precast concrete sills are sold by the linear foot. The esti-

mator should check the maximum length of stone and pre-

cast concrete sills required and note it on the takeoff.

Also to be checked is the type of sill required: A slip sillis

slightly smaller than the width of the opening and can be

installed after the masonry is complete. A lug sill,which extends

into the masonry at each end of the wall, must be built into the

masonry as the job progresses. Some specifications require spe-

cial finishes on the sill and will have to be checked. Also, if dow-

els or other inserts are required, that fact should be noted.

Coping. Thecopingcovers the top course of a wall to pro-

tect it from the weather. It is most often used on parapet

walls. Masonry materials used include coping block, stone,

tile, and precast concrete. Check the specifications for the

exact type required and who supplies it. The drawings will

show the locations in which it is used, its shape, and how it is

FIGURE 11.17.Typical Wall Ties and Wall Tie Installation.

(Courtesy of Dur-O-Wall)