134 CHAPTERELEVEN
11–20 Equipment
The equipment required for laying masonry units includes the
mason’s hand tools, mortar boxes, mortar mixer, hoes, hoses,
shovels, wheelbarrows, mortar boards (tubs), pails, scaffolding,
power hoist, hand hoist, elevator tower, hoisting equipment,
telehandlers (long-reach forklifts), and lift trucks. The estima-
tor must decide what equipment is required on the project,
how much of each type is required, and the cost that must be
allowed. The estimator must also remember to include the
costs of ownership (or rental), operating the equipment, and
mobilization to and from the project, erection, and disman-
tling. Items to be considered in determining the amount of
equipment required are the height of the building, the number
of times the scaffolding will be moved, the number of masons
and helpers needed, and the type of units being handled.
11–21 Cold Weather
Cold weather construction is more expensive than warm
weather construction. Increased costs stem from the con-
struction of temporary enclosures so the masons can work,
higher frequency of equipment repair, thawing materials,
and the need for temporary heat.
Masonry should not be laid if the temperature is 40°F
and falling or less than 32°F and rising at the place where the
work is in progress, unless adequate precautions against
freezing are taken. The masonry must be protected from
freezing for at least 48 hours after it is laid. Any ice on the
masonry materials must be thawed before use.
Mortar also has special requirements. Its temperature
should be between 70°F and 120°F. During cold weather
construction, it is common practice to heat the water used to
raise the temperature of the mortar. Moisture present in the
sand will freeze unless heated; upon freezing, it must be
thawed before it can be used.11–22 Subcontractors
In most localities, masonry subcontractors are available. The
estimator will have to decide whether it is advantageous to use a
subcontractor on each project. The decision to use a subcontrac-
tor does not mean that the estimator does not have to prepare an
estimate for that particular item; the subcontractor’s bid must be
checked to be certain that it is neither too high nor too low. Even
though a particular contractor does not ordinarily subcontract
masonry work, it is possible that the subcontractor can do the
work for less money. There may be a shortage of masons, or the
contractor’s masonry crews may be tied up on other projects.
If the decision is made to consider the use of subcon-
tractors, the first thing the estimator should decide upon is
which subcontractors she wants to submit a proposal for the
project. The subcontractors should be notified as early in the
bidding period as possible to allow them time to make a
thorough and complete estimate. Often the estimator will
meet with the subcontractors to discuss the project in gen-
eral and go over exactly which items are to be included in the
proposal. Sometimes the proposal is for materials and labor,
other times for labor only. Both parties must clearly under-
stand the items that are to be included.EXAMPLE 11-4 MASONRY TAKEOFF
Figures 11.20 and 11.21 are the completed masonry takeoffs for the
commercial building found in Appendix A.
FIGURE 11.20.Gross Wall Area.