Computerized estimating: The A-B-C-D-E-F and Gs

Back in 1982-1983, I was the systems analyst and mechanical trades consultant for the second digitizer-based computerized construction estimating system ever created. So, I’ve seen these systems’ slow but inevitable acceptance. The simple fact is that they work and they make their owners and users money.

For those of you considering buying a system but who haven’t yet made the commitment, I present below a basic primer on computerized estimating systems, along with their strengths and weaknesses.

Computerized systems have two basic efficiencies that manual estimating can’t offer. One is provided by the standard database (which can be customized) of labor and material costs for each individual foot of pipe, pound of sheet metal or system accessory that is present in the system’s software.

When an estimator enters any item into the running bid file, he does not have to go to the mcaa or phcc manual to look up labor units, then go to a vendor pricing book to get the wholesale price of an item, then manually extend out both on pricing sheets. All that and more is part of the system’s “engine,” which will drive and print out a fully fleshed-out report when the estimate is done.

Second, the digitizer is so bloody accurate when picking off lengths or dimensions or counts (more on this shortly) as to be almost scary at times.

That said, you need to keep in mind the geek-speak acronym “gigo,” for “garbage in, garbage out.” A digitizer-based estimating system, for all the hype you’ll hear from different vendors, is nothing more than a giant calculator. Calculators must have correct input from a human being to obtain the desired output. To produce a better, more accurate estimate than what you’re used to having, you’ll still need to have a first-class, for-real estimator who has excellent trade knowledge and good estimating habits to actually work the system.

The basic system components always consist of the following:

A digitizer. This can be a roll-up mat that can be placed on any large, flat surface for the plan sheets to be placed on top of, or it might be a stand-alone piece of furniture.

Computer system “hardware” — the pc, monitor, mouse, keyboard, etc.

The estimating software that resides on the computer’s hard disk and actually takes the repetitive, boring, monotonous work off the estimator’s back.

Many estimators learned how to use their systems when their bosses sat them down at their new systems and said, “Here it is, go for it!” The trial-and-error time they took to learn the system always cost their employer much more in dollars spent on salary and lost efficiency than would have been spent if their bosses had sent them to the vendor’s school. Every system vendor offers training for a price. Even with paying your estimator’s tuition, airfare, hotel, per diem and rental car, you still can save money in the short and long run by sending him to a two- to four-day school to learn how to get the most of out the expensive system you just bought him.

Strengths. As mentioned in “A,” the main strength of the system is the accuracy of the digitizer when taking off lengths of pipe or dimensions of metal. The precision can be in the fractions of a fraction of an inch. The second most important strength is flexibility. Let’s say the estimate is done, and then you get an addendum to the specs where the engineer has changed the sheet metal.