Estimating in Building Construction

90 CHAPTER NINE

Check the soil borings for the kind of soil recorded and
the approximate depth the piles must be driven. The accu-
racy of this information is quite important.

Specifications. Check the type of piles required and under
what conditions sheet piling is required. Any requirements
regarding soil conditions, equipment, or other special items
should be noted. Many specifications require that only firms
experienced in driving piles be allowed to do so on the job.

9–20 Pile Checklist

Ty p e :

wood

wood and concrete

H-piles

casing and poured in place

poured in place

precast

wood sheets

steel sheets

precast sheets

bracing

Equipment:

pile driver

compressors

derricks

cranes

9–21 Asphalt Paving

The asphalt paving required on the project is generally sub-
contracted to someone specializing in paving. The general
contractor’s estimator will make an estimate to check the
subcontractor’s price.
Asphalt paving will most commonly be hot-mix and is
generally classified by traffic (heavy, medium, or light) and
use (walks, courts, streets, driveways, etc.).

The estimator will be concerned with subgrade prepara-

tion, subdrains, soil sterilization, insulation course, subbase

course, base courses, prime and tack coats, and the asphalt

paving required. Not all items are required on any given pro-

ject, so the estimator should determine which items will be

required, the material and equipment necessary for each

portion of the work, and the requisite thickness and amount

of compaction.

Specifications. Check the requirements for compaction,

thickness of layers, total thicknesses, and materials required

for each portion of the work. The drawings will also have to

be checked for some of these items. The drawings will show

the location of most of the work to be completed, but the

specifications should also be checked. The specifications and

drawings will list different requirements for the various uses.

(These are called traffic requirements.)

Estimate. The number of square feet (or square yards)

of surface area to be covered is determined, and the thick-

ness (compacted) of each course and the type of materials

required are noted. Base courses and the asphalt paving

are often taken off by the ton, as this is the unit in which

these materials must be bought. The type of asphalt and

aggregate size required must also be noted. Two layers of

asphalt paving are required on some projects: A coarse

base mix may be used with a fine topping mix. Equipment

required may include a steel-wheel roller, trailers to trans-

port equipment, dump trucks, paving machines, and vari-

ous small tools.

To estimate the tons of material required per 1,000 sf of

surface area, refer to Figure 9.44. Different requirements will

be listed for the various uses (walk, driveway, etc.), and the

different spaces must be kept separately.

In many climates, the asphalt paving has a cutoff date in

cold weather, and the paving that is not placed when the

mixing plants shut down will not be laid until the start-up

time in the spring. The plants may be shut down for as long

as four months or more, depending on the locale.

FIGURE 9.44.Approximate Asphalt Paving Materials Tonnage.