Determining material costs can be the least confusing part of the estimating process. Sources for material prices may range from anticipated to precise.

In most cases, barring major errors, the material costs should reflect at least part of the project. Never to be lulled into complacency, the estimator must always be aware of material trends, if not the actual costs.

Copper prices are often considered among the least predictable. However, even they can be somewhat predictable if the estimator reviews commodity market activity prior to purchasing great quantities. Unforeseen icebergs are circumstances that brought about a surcharge years back. During the heady days when a team of brothers cornered the silver market, prices for switchgears that use silver-plated bus bars fluctuated wildly. Eventually, quotes were provided that left the surcharge open to the price of silver at the time of switchgear delivery.

Selecting the optimum labor factor for a project is too difficult for the fledging estimator to do alone. For starters, labor units and their application methods are similar to a Ouija board: The resultant choice of labor units may or may not be based on solid facts. If the estimator were to consider the generic task of installing one-half-inch EMT on a wooden surface, it would indicate that the range could be from 2.5 to 6.5 hours per 100 feet, and higher.

Why is there such a spread of labor units? The answer lies in factors included in the labor unit. For example, the grandparent of all labor units, the NECA Manual of Labor Units, includes such tasks as: material handling; plan study; job layout; moving tools to and from the installation point; measuring, cutting, and threading conduit as needed; installing the material; making bends; and nonproductive labor. Following this list is a set of tasks that are not included, but necessary, such as the fastenings and elbows.

There are sufficient variances in the sole process of installing EMT to make the correct application of labor units a daunting task.

When comparing labor units, consider the scope of the job to be done, just as you would in preparing a project bid. Many labor tables are, at best, too brief, and at worst, absent of the scope of the labor unit.

A labor unit is comprised of a variety of subjective factors dependent upon the individual contractor's operations. The labor unit includes the study of the plans that can comprise up to10 percent of a labor's hour. Ordering materials and getting tools to the job can eat up another 10 percent of a labor unit; this can emphasize the need for efficient purchasing and warehousing operations. Unless the installation is small enough to be accommodated by stocked trucks, time must be allotted for receiving and storing materials and tools.

On larger sites, as much as five percent of the labor can be eaten up by moving the materials from the storage point to the point of installation.

Efficiency of tooling can use up to 35 percent of installation time, but this time will be readily offset by a comparable or shorter installation time. No matter how simple a project, two to five percent of the time must be allocated to layout and measuring. If all goes well, installation time of an item can be as low as 35 percent, while a badly run operation can be as high as 80 percent.

One of the inevitable items omitted for consideration in labor units is the job cleanup. While this should be done with the less expensive help, it can still burn up as much as five percent of the installation time. Another "downer" is the up to six percent of nonproductive time, but this is much greater if the support of the project fails in any one area.

There is no such thing as the perfect labor table; there is nothing equivalent to the labor manuals used by your local garage to provide an estimated labor figure. The estimator must select a set of tables that will be, at best, a basic guide.

A method to determine the reasonable accuracy of a labor unit is to make a task analysis,which is a fairly common procedure with a fancy name. Such an analysis lists the various steps involved in making an installation in the most elementary fashion - no item can be omitted no matter how routine it is. Estimators may want the company's well-experienced field personnel to help, and should not be bashful to ask for it.

At times a task analysis may be performed to verify a labor unit to make future bids more competitive. If this is its purpose, the field people should be so advised. With such knowledge, .some skeptics maintain that the production may be unrealistic, but that can be overcome.
Avoid such unannounced methods as installing a time-lapse camera. You may find that, when the film is retrieved, people on the job saw the camera and put a cardboard box over it.

Whenever the topic of the NECA Manual of Labor Units is discussed, invariably a skeptic will complain that, if one uses the labor units, no one would ever get a job. That statement is a fact if the labor units are used blindly, without considering the scope or the quantities and varying conditions on which the labor units are based. One of these conditions is that the labor units are based on projects of 20,000 to 100,000 square feet - quite a spread, and there are many other similar conditions listed in the introduction to the Manual. Obviously the labor units will not reflect the varying conditions we find in our vast country and types of work.

The variances of labor units must be considered at all times. An inflexible set of labor units based on false assumptions that does not account for a differential of work may be a fool's folly. Labor units have a life of their own and must be treated as such.

DAVID is a professor of electrical technology at Long Beach City College, Calif., a consultant and an expert witness. He can be reached at (562) 597-1877or by e-mail at