Ecmweb 5946 Est

Your Estimate and the National Electrical Code

Nov. 15, 2013
Why a good estimator doesn’t assume the design engineer has covered everything required by the Code in a bid’s supporting documents.

"I don’t have to worry about the Code. I’m just the estimator responsible for plans and specs.” Every responsible estimator knows this is not the case — that codes come into play on every job that is bid. In fact, one of the first statements an estimator reads when reviewing bid documents is, “All work shall conform to the applicable requirements of the Authorities Having Jurisdiction (AHJ), including the latest National Electrical Code (NEC), ordinances and amendments, other referenced codes, and the Americans With Disabilities Act (ADA).” This means, regardless of what is shown (or not shown) on the drawings or listed in the specs, a contractor is responsible for a “code-compliant” job.

This is when things get tricky from an estimating standpoint, as code compliancy may not be the sole intent of the designer and engineer. Navigating your way through the drawings and determining whether or not the project documentation reflects code compliancy makes an estimator a virtual engineer. Again, you cannot assume the engineer has considered all of the possibilities or is even well versed in the Code for that matter.

Estimating a project and ensuring its code compliancy go hand in hand. The customer expects a code-compliant project, even though it may not be depicted on the drawings. No doubt there is typically a note in the specs regarding conflicts, stating that in the event of a discrepancy (between items shown on drawings or explained in the specs), the electrical contractor is responsible for “the greater quantity and/or the more expensive option.”

Is the NEC a law or just a guideline?

By way of background for the less familiar, the NEC is a product of the National Fire Protection Association (NFPA), an organization that writes and produces copyrighted standards and codes for usage and adoption by local governments and agencies. The NEC is also known as NFPA 70, which covers the standards for safe installation of electrical wiring and equipment. Although the NEC is not an actual law per se, it is used by AHJs as an applicable requirement for most construction projects.

The NEC is also used in conjunction with other codes and standards produced by other national agencies. For example, while the NEC governs the installation of electrical materials, the ADA governs the mounting heights and locations of devices such as switches and receptacles. The NEC also works in conjunction with NFPA 72, which outlines provisions for fire detection, signaling, and emergency communications in the event of fire and weather emergencies, terrorist events, and other threats.

I don’t really know how to use my Code book, so how can I apply it to my estimate?

Knowing how to use the Code and apply its requirements to your estimate is a critical piece of your estimating and bidding functions. The NEC is organized by chapter. Chapters 1 through 4 cover installation of items while Chapters 5 through 7 address special occupancy, equipment, or conditions. Chapter 8 covers communications, and Chapter 9 contains tables for references such as wire fill tables. When reviewing your project documentation, you will often see references to a certain code item. For example, 230.8 can be found in Chapter 2 [Wiring and Protection]. As you scroll through Chapter 2 and find Sec. 230.8, you will see this section of the Code addresses “raceway seal” and how it applies to your estimate.

Which edition of the NEC do I use in my area?

Drawings will typically refer you to the “latest National Electrical Code,” which is actually the 2014 edition. However, this may not be the edition of the Code that has been adopted by the AHJ or local state, municipality, or county where your estimate applies. Some areas of the country are still using the 2005 edition of the NEC, for example. The reason for this is because Code adoption is not a national mandate. Each state, municipality, or county has jurisdiction over which edition of the Code it adopts. In other words, a state may adopt the 2011 edition of the NEC statewide, while another state leaves it up to individual municipalities or counties. This is very important to know in terms of your estimate because many Code requirements change from edition to edition. If you are referencing a specific section of the NEC, you must make sure you’re using the proper edition based on where the work is being performed. Finally, check to make sure that the local state or AHJ has not made any modifications or amendments to the specific edition of the NEC they have adopted.

Need more information on Code adoption dates? Check out the NFPA website (www.nfpa.org) and search for “NFPA 70 Code adoption,” where you can reference your state and see what version of the Code is in place.

When it comes to surgery centers, the AHJ may require health care-rated cable in the entire facility, not just the patient care areas.

What are some examples of applying the code to my estimate?

Now that we have established you are responsible for a code-compliant project — if certain notes exist in any of your project documentation — let’s take a look at a few real-world examples of what you may come across.

Doctor’s office — Our first example involves a doctor’s office fit-out in an existing office building. The plans do not show (nor do they mention) health care-rated cable. What do you do? Knowing you are responsible for a “code-complaint” project, you should review Chapter 5 of the NEC, which addresses “Special Occupancies,” and more specifically Art. 517 [Healthcare Facilities]. In this scenario, pay special attention to wiring methods. An excerpt from the 2011 NEC states the following:

“517.12 Wiring Methods. Except as modified in this article, wiring methods shall comply with the applicable requirements of Chapters 1 through 4 of this Code.”

As noted in the next section of this version of the NEC, you must also take note of the following grounding requirements.

“(A) Wiring Methods. All branch circuits serving patient care areas shall be provided with an effective ground-fault current path by installation in a metal raceway system, or a cable having a metallic armor or sheath assembly. The metal raceway system, metallic armor cable, or sheath assembly shall itself qualify as an equipment grounding conductor in accordance with 250.118.”

In other words, unless modified by the special condition of a health care facility in Art. 517, all wiring methods as described in Chapters 1 through 4 of the Code are in effect. Section 517 requires two separate ground paths for all electrical equipment in patient care areas. The definition of a patient care area, “any portion of a health care facility wherein patients are intended to be examined or treated,” can also be subject to interpretation by the AHJ. In addition, some inspectors want all equipment within the facility to have dual grounding paths.

If you decide to go the “less expensive” route and not run health care-rated cable because it is “not shown or specified,” you might be setting yourself up for a future battle. Although your chances of being awarded the job will improve with this approach, be aware that the AHJ/electrical inspector may require this wiring arrangement — and you will not have much of an argument to make the case for a future change order.

Day surgery facility — Continuing on with another health care scenario, let’s consider a day surgery center. From the previous example, you know you will need to run health care cable in patient care areas. You also know that the AHJ may require health care-rated cable in the entire facility, not just the patient care areas. However, you have a few more things to consider in this scenario. Section 517.18 details requirements for “general care areas” while 517.19 addresses “critical care areas.”

Patient beds in general care areas may require at least two branch circuits — one regular and one emergency. However, you still must consult the Code because exceptions do apply based on facility type. Also, the NEC states that each patient bed area will require a minimum of four receptacles, and those receptacles shall be rated as “hospital grade.”

So we have now exposed two items you should address in your bid. The first is emergency power, namely a generator and transfer switches. The second is hospital-grade devices. If your project documentation does not address either of these, it is time for you to issue a request for information (RFI) from the general contractor who is soliciting the bid. Generators are high ticket items, so you want to be sure to cover the cost and/or determine whether you actually “own” the emergency power system. In terms of hospital-grade devices, they are more expensive than a typical receptacle because they are much more durable and have to withstand a number of tests — whereby items have to be plugged into these receptacle at odd angles, repeatedly, without degradation of the receptacles or sparking.

In critical care areas (Sec. 517.19), power must be supplied by the normal system and the emergency system like above, with an additional stipulation regarding dedicated circuits and additional outlets.

Car dealership — In our next scenario, a car dealership with an oil change area (i.e., pit) is being built. There are several items shown in the pit, such as a sump pump, cord reel, jelly jar light fixture, and duplex receptacles. Even if it is not shown on the drawings, the oil change area/pit is defined by the Code as having a certain Class/Division. This means the design must include explosionproof equipment. Article 500 focuses on hazardous (classified) locations. In this example, the design is classified as Class 1, Div. 1 location. Article 501 addresses Class 1 locations, including wiring methods and types of devices that are required to be explosionproof.

Facility with a kitchen having a hood and fire suppression system — Here is a great example of the NEC working in conjunction with other codes, such as the life safety code, NFPA 101, and fire alarm code NFPA 72.

In scenarios where there is a kitchen with a hood system, and electrical items are shown beneath the hood, they will require protection with a shunt trip. Most project drawings will note that a shunt trip breaker will be required in this scenario. If it isn’t noted, carry it anyway and qualify your bid. Other items to consider include lights, make-up air units, and receptacles. If all appliances are circuited through the same panel, you can use a shunt trip on the main of that panel. If these items are circuited to different panels, each must be protected by its own shunt trip breaker at their respective panels. Another option for you to consider is the use of a contactor, which can also shut down devices. When the kitchen hood fire suppression system is activated, the shunt trip will shut down power to all electrical equipment protected by it, and the fire alarm system will activate. The important point to note here is that the NEC does not operate in a vacuum. Other codes and standards come into play on almost every project.

I am more confused than ever. What do I do now?

The NEC guides the installation of electrical products, such as devices and wiring. It also addresses special installation circumstances or conditions. In addition, the NEC works in conjunction with other codes and standards. Although the information contained in the NEC is vast, it is well organized and easy to use once you gain experience in applying its requirements. Problems can arise, however, where items are subject to interpretation. Plus the AHJ can always throw the proverbial monkey wrench into the mix at any given time. So thoroughly review all project documentation, especially the notes, and never assume anything. Finally, make sure your own copy of the NEC is readily available at all times.               

Candels is one of the principal owners of Candels Estimating, an outsourced electrical firm with four locations nationwide. She can be reached at [email protected].

About the Author

Linda Candels

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