Upgrading the Lair: Estimating work for an existing lair

By Stephen Carr | Oct 15, 2022
My grandson was recently in town for a family event.




My grandson was recently in town for a family event. You may recall he had asked me to prepare an estimate for a secret lair a while ago (“The Makings of a Secret Lair,” ELECTRICAL CONTRACTOR October 2021). It turned out my grandson could not afford the new lair, but his imagination never stopped working, and he is now asking about an upgrade.

The new scope includes advancements to the computer system, adding more cameras to the security system and expanding the dragon training facilities. (My grandson is a very successful trainer.) Of course, the HVAC, power and lighting systems will need to be upgraded to handle the additional spaces. This will also require an expansion of the existing switchgear and feeder system.

Among the many project types I prepare estimates for, making upgrades to an existing facility is one of the most difficult to complete. There are several reasons, including continuity of services, space for new equipment and routing new conduits.

Continuity of service

Most upgrades require shutting all or some of the power off. It may be just for one weekend or require multiple shutdowns to complete various phases of a project. If there are critical loads that cannot be without power for an extended period, the electrical contractor is responsible for providing temporary power, usually in the form of generators. 

For the estimate, remember to include the cost of the generator, fuel and all materials needed to make the temporary connections. Include the cost of using and maintaining the temporary equipment you own, and the cost of removing the temporary power equipment and installations when you are done.

For the lair upgrade, the dragon facilities are critical. The temperature and humidity must be maintained, as well as water, feed and sanitary systems. (I don’t want to try to imagine what sanitary systems for a dragon lair look like.) There will be shutdowns for the additions to the switchgear at a minimum, and possibly more as expansions to the other systems are brought online. The costs for these shutdowns must be carefully studied and accounted for.

New equipment

Fortunately, our original lair design included an electrical service with substantial spare capacity. I have learned the hard way that most clients underestimate their future needs. However, the power system will need new coordination, short circuit and arc flash studies because of the new loads. We also designed the electrical rooms with capacity for future equipment. 

Unfortunately, many of the upgrade projects I prepare estimates for do not anticipate future growth. Also, many of the engineered designs do not adequately lay out where to put the new equipment, leaving the problem to the electrical contractor. Be suspicious of any design provided. About 50% of the upgrade designs I receive will not work, most often due to insufficient space as required by the Code.

Routing of conduits

Conduit routing is often a nightmare in upgrade projects. I highly recommend attending job walks, if they are offered. Another tool that helps me visualize conduit routing for outdoor installations is Google Earth. It is not perfect, but it does offer side views for many locations. 

These alternate views often reveal issues the drawings do not show. Similar to equipment placement, the drawings often misrepresent where feeders can be installed. If you are forced to make significant routing changes for your estimate, remember to qualify the proposal as needed to protect yourself.

An example of a feeder nightmare was a historical theatre remodel project I bid earlier in my career. Racks of 4-inch conduits were shown routed in the basement. During the job walk, I discovered the ceiling height was far too low to make this installation. I included a possible alternate for routing in my estimate. Unfortunately, I was not the low bidder and was unable to find out what the solution was.

For our lair upgrade, we benefited from spare capacity on the conduit racks and spare conduits that were part of the original design. I see designs with this kind of forethought on some industrial projects, but I almost never see it on commercial work.

Final thoughts

There are some other considerations when bidding work in existing facilities, including working in occupied spaces, premium labor (overtime) requirements and restricted access to the work areas. Also, difficult installation situations, such as working through a T-bar ceiling, must be considered when factoring in your labor units. 

My grandson has some training seminars coming up, and he wants the upgrades completed in three months. I guess he’s no different than my actual clients.

Header image by Wesley J. Clark.

About The Author

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 [email protected], and read his blog at

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