Because everything’s connected—somewhere:
Do you know what integrated systems are and how to estimate them? They’re not really that different from standard low-voltage systems, but they require more attention to the drawing details and specifications. As with the many other rapidly changing technologies and designs we are faced with, estimators need to know what integrated systems really are before they can estimate them correctly.
For many years, standard low-voltage systems—telecom, security, fire alarm, CATV, etc.—have always been considered to be separate from and independent of each other. Over the past decade, the need for computerized control, monitoring and higher-tech coordination has connected them together—thereby integrating them.
Lighting systems now are integrated with the HVAC controls system, better known as the energy-management system (EMS). This integration allows these two systems to be controlled from a networked computer or even by a service technician using a remote laptop computer.
This probably is one of the most involved integrations and one that could impact the electrical contractor more than any other system. In order to achieve this integration, additional relays, sensors and control modules are required. These require labor to install. They also involve more wiring, which requires more conduits, boxes and supports—all of which involve more material and labor costs.
A word of caution: Study your lighting circuitry, switching and any lighting controls diagrams carefully, and watch out for any broad-scoped sheet notes. Some engineers are not fully aware of exactly how these new lighting control systems and their integration to the EMS actually get wired. This is especially true with lighting fixtures on emergency circuits controlled by the EMS.
We see a lot of integration also with audio-visual systems. The computerized control of projectors, motorized shades and curtains, audio levels, lighting and dimming systems potentially requires more relays, wiring and conduits. Security and CATV systems are other highly integrated systems.
In my past two articles, I discussed how important it is to know your company’s complete scope of work. This critical knowledge also applies to integrated systems. You must find out what each system requires from the other, how they communicate with each other and how they are integrated.
This information is not always going to be shown in the electrical design, drawings or details. It may not even be shown in the signal, telecom or security drawings. There is a chance the integration connections will be shown on one of the signal riser diagrams, or perhaps stated in a few sheet notes. Most likely, the integration requirements will be discussed in the specifications section. So it is critical you thoroughly read all of the specifications and determine which systems, if any, are integrated and how.
Smaller electrical contractors may not be the one providing or installing these systems, only installing the rough-in conduit systems for them. In that case, the company may solicit quotations from several low-voltage subcontractors, and depending on the job, there likely will be more than a few different ones.
Regarding subcontractors, it is important they know each other’s complete scope to making sure everything is covered and nothing is duplicated. I recommend discussing the integration requirements with each of the subs to find out exactly what they know and what they will be carrying in their quotation.
Most of the integration is done by the control panels, computer systems or at the electronic equipment racks using patch panels with patch cords and interface cards. Each low-voltage system contractor should cover this work. As an estimator, there is not much you need to do about this (unless your company is the system’s contractor).
However, low-voltage systems typically require conduits and cables. Both require material and labor costs. If two systems are integrated, the electrical contractor likely is the one responsible for installing any inter-connecting conduits and possibly the cables. As an estimator, you must make sure these costs are covered in your estimate—either by you or your subcontractor’s quotation. Chances are this is not a major portion of the project but still costs to be carried.
Example: An interconnecting conduit could be (1) 4 in. with (3) 1 in. inner-ducts and 24 strand multimode fiber optic cables. What if the distance is 200 feet, underground, across an existing parking lot and into the building across the street, where it connects to the existing campus system? Now, this scenario is most likely shown on the drawings, but it might be only discussed in the specifications. If you assumed all things required were shown on the plans or were covered by your subs, you may have just lost a few thousand dollars of profit.
Knowing which systems are integrated, how they are connected and what their related costs are will make your estimate more complete. And obviously, it’s much better to carry these additional costs in the estimate pre-bid than having to tell the boss you missed them—after the bid. EC
Shook is the president and chief estimator for his estimating company, TakeOff 16 Inc. He has worked in the electrical construction industry for more than 18 years. Reach him at 707.776.0800 or by e-mail at