128 CHAPTERELEVEN
11–11 Specifications—Tile
Check the specifications for the type, size, and special
shapes of the tile. The type, thickness, and color of mortar
must be noted as well as the type of lintels, flashing, and
reinforcing.
A wide variety of glazed finishes and special shapes are
available. The specifications and drawings must be studied
to determine the shapes required for the project. Because
special shapes tend to be expensive, they should be estimated
carefully. Be certain that the materials specified meet all
ASTM specifications.
11–12 Estimating Tile
Hollow masonry units of clay tile are estimated first by the
square feet of wall area required, each thickness of wall
being kept separate. Then the number of units required is
determined.
To determine the amount of tile required for a given
project, the first step is to take off the length, height, and
thickness of units required throughout. All openings should
be deducted. Check the details for any special shapes or cuts
that might be specified.
When the total square footage of a given thickness has
been determined, calculate the number of units. Figure the
size of the unit plus the width of mortar joint; this total face
dimension is divided into square feet of masonry to deter-
mine the number of units.
The labor costs will be affected by jogs in the wall, open-
ings, piers, pilasters, weather conditions, and the height of
the building. Items that need to be included are mortar, lin-
tels, flashing, reinforcing, weep holes, and any special shapes.
11–13 Stone Masonry
Stone masonryis primarily used as a veneer for interior and
exterior walls; it is also used for walkways, riprap, and trim
on buildings. Stone masonry is usually divided into that
which is laid up dry with no mortar being used—such as on
some low walls, sloping walls, walkways, and rip-rap—and
wet masonry, in which mortar is used.
Stone is used in so many sizes, bonds, and shapes that a
detailed estimate is required. The types of stone most com-
monly used are granite, sandstone, marble, slate, limestone,
and trap. The finishes available include various split finishes
and tooled, rubbed, machine, cross-broached, and brushed
finishes. Stone is generally available in random, irregular
sizes, sawed-bed stone, and cut stone, which consists of
larger pieces of cut and finished stone pieces. Random,
irregular-sized stone is used for rubble masonry and rustic
and cobblestone work; it is often used for chimneys, rustic
walls, and fences. Sawed-bed stones are used for veneer work
on the interior and exterior of buildings. Patterns used
include random and coursed ashlar. Coursed ashlar has reg-
ular courses, whereas random ashlar has irregular-sized pieces
and generally will require fitting on the job.
11–14 Specifications—Stone
Check exactly the type of stone required, the coursing, thick-
ness, type, and color of mortar as well as wall ties, flashing,
weep holes, and other special requirements. Not all types
and shapes of stone are readily available. The supplier of the
stone must be involved early in the bidding period. For large
projects, the stone required for the job will actually be quar-
ried and finished in accordance with the specifications. Oth-
erwise, the required stone may be shipped in from other
parts of the country or from other countries. In these special
cases, estimators place a purchase order as soon as they are
awarded the bid.11–15 Estimating Stone
Stone is usually estimated by the area in square feet, with the
thickness given. In this manner, the total may be converted
to cubic feet and cubic yards easily, while still providing the
estimator with the basic square foot measurement. Stone
trim is usually estimated by the linear foot.
Stone is sold in various ways—sometimes by the cubic
yard, often by the ton. Cut stone is often sold by the square
foot; of course, the square foot price goes up as the thickness
increases. Large blocks of stone are generally sold by the
cubic foot. It is not unusual for suppliers to submit lump-
sum proposals whereby they will supply all of a certain type
of stone required for a given amount of money. This is espe-
cially true for cut stone panels.
In calculating the quantities required, note that the
length times height equals the square footage required; if
the number must be in cubic feet, multiply the square
footage by the thickness. Deduct all openings but usually
not the corners. This calculation gives the volume of mate-
rial required. The stone does not consume all the space; the
volume of mortar must also be deducted. The pattern in
which the stone is laid and the type of stone used will
greatly affect the amount of mortar required. Cut stone may
have 2 to 4 percent of the total volume as mortar, ashlar
masonry 6 to 20 percent, and random rubble 15 to 25 per-
cent. Waste is equally hard to anticipate. Cut and dressed
stone has virtually no waste, whereas ashlar patterns may
have 10 to 15 percent.
Dressing a stone involves the labor required to provide a
certain surface finish to the stone. Dressing and cutting stone
require skill on the part of the mason, which varies consider-
ably from person to person. There is an increased tendency
to have all stone dressed at the quarry or supplier’s plant
rather than on the job site.
The mortar used should be nonstaining mortar cement
mixed in accordance with the specifications. When cut stone
is used, some specifications require that the mortar joints be
raked out and that a specified thickness of caulking be used.
The type and quantity of caulking must then be taken off.
The type, thickness, and color of the mortar joint must also
be taken off.