More Estimating, Less Engineering: Dealing With Mistakes and Contradictions in Bid Documents

Estimating Request for Information Photo Credit: Shutterstock / Olivier Le Moa
Photo Credit: Shutterstock / Olivier Le Moa
Published On
Mar 15, 2019

After finishing last month’s article, I was immediately reminded that there are more problems with today’s bid documents I did not cover. Many of these issues could cost you money if you don’t detect them while completing an estimate. Let’s look at a few of these problems and come up with some strategies for dealing with them.

Conflicts and contradictions

Here is an example from a project I bid a few months ago. While creating a specification outline, I found multiple requirements for underground conduit. First, a general requirements section called for GRS conduit, direct buried. Next, the conduit and raceway section required PVC40 encased in concrete. Then, the underground section required PVC-coated GRS direct buried for some conduits and PVC40 encased for others. Finally, details and notes on the plans conflicted with the specifications regarding materials and methods. What a mess.

There are several strategies for dealing with these kinds of problems. My first concern would be regarding making an interpretation without clarification. This presents two problems. Could the wrong interpretation of these conflicts cause my bid to be high and make me lose the bid, or could it cause my bid to be too low and cause financial losses if I am the low bidder? My next concern is whether my competitors are likely to miss this problem and have a more competitive bid than me because of it.

If you are concerned about these questions, it’s time to submit a request for information (RFI). I like this strategy because the answers are usually returned as an addendum, requiring all bidders to include the proper costs. Another strategy is to add qualifications to your bid proposal. I use this strategy when I do not want to add dollars to my proposal. Instead, I will use a qualification to clarify what is included in my bid when the bid documents are not clear.


Another problem with today’s drawings is an excessive number of notes. Early in my career, only the most complex projects used a lot of notes. Notes were used only when the work could not be shown on the drawings due to factors such as complexity or hidden conditions. Today, even the simplest projects can have more than 30 notes on a page.

Notes can be dangerous if not carefully interpreted. All too often, they are vaguely worded, as if they are poor translations from another language. For instance, “The branch circuit shall simultaneously all underground conductors.” That one wasn’t too hard to figure out. It was regarding circuit breaker ties for multicircuit home runs. Often, poorly worded notes end up requiring an RFI. Sometimes, notes simply do not contain enough information.

One such note simply stated, “Provide for electric vehicle charging.” There was no other information on the electrical and architectural plans. Maybe all they wanted was a 20-ampere (A) outlet for charging a small electric scooter. Maybe they wanted 400A of power with a panel and feeders installed to all locations. Beyond that, they may want you to provide the charging stations.

Another dangerous situation is long, complex notes. When dealing with this type of note, I process each individual scope of work in the note separately. Mark off each portion of the note only when the takeoff is done. An example of a note with several scopes would be one that specifies a transformer size, primary feeder, secondary feeder and then the grounding.

Design mistakes

I often find designs that do not meet the National Electrical Code (NEC) or local electrical codes. One design error I often find regards electrical fire pumps. The wiring for these pumps is very different from standard wiring and has its own section in the NEC. Basically, the feeders for these pumps must be tapped from the incoming power before any fuses or circuit breakers and must be sized at the locked-rotor amperage of the motor. This means the feeders can get very hot, requiring special installations to protect the structure. Familiarize yourself with these requirements before estimating this kind of work.

Two more common mistakes are violations of the 10-foot tap rule and not protecting transformer secondaries. Check your Code book to fully understand these requirements. Sometimes, engineers simply forget to put circuit protection within 10 feet. Other times, the design does not consider the additional wire it takes to get the wire into an enclosure. If the conduit is 10 feet long, the wire must be at least 15 feet long.

The specifications always have a section that requires you to build as required by the NEC. If the design mistakes are big, use an RFI or qualification to protect yourself.

About the Author

Stephen Carr

Estimating Columnist

Stephen Carr has been in the electrical construction business since 1971. He started Carr Consulting Services—which provides electrical estimating and educational services—in 1994. Contact him at 805.523.1575 or, and...

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