Renovation 2010

There are different types of lighting retrofit projects: fixture replacement, relocation, repair, ballast retrofit, clean and relamp only, and various other fixture-related tasks; some projects may not even involve working with existing lumminaires. As green building takes an even stronger hold of our industry, the focus of most projects will likely be adding to or enhancing the lighting control systems. So along with swapping out ballasts, replacing fixtures and reconfiguring overhead circuitry, there may be many new switches, sensing devices, signal cabling and control panels with which to deal.

The success or failure of your estimate will depend strongly on how much information you have about the existing fixtures, circuitry and your knowledge of the new control systems. Perhaps most importantly, it will depend on how you labor it all.

Know the complete scope!

This is so critical. You must read every sheet note thoroughly and study the entire specification manual, not just the lighting spec. Engineers love to hide little notes, such as general conditions and wiring devices, deep in other specification sections. And don’t forget to study the Division 01 Scope of Work documents or similar directives, which usually are issued to the general contractors.

Thoroughly study the architectural drawings to learn and/or verify what is happening with the ceilings. If the entire ceiling in an area is getting replaced, it is likely all the fixtures in that area will need to be taken down. However, if the ceiling is a T-bar type, the fixtures might be able to stay in place. Details such as this can have a major effect on your total estimated labor.

The same goes for researching and knowing which walls are getting removed or resurfaced, as there may be lighting fixtures, exit signs and related control devices that need to be removed and replaced. Sometimes, these fixtures and devices are not shown on the electrical drawings. What will you carry if they are not shown?

‘Intercept, connect to existing systems’

This is one of the most vague, nondescript and scary sheet notes. Engineers often use this sheet note because they don’t have a clue as to how this work should be done or if it can be done at all. The bigger problem is neither do you.

Unless you are able to spend several hours or days at the job site prior to the bid—combing through the ceiling, opening junction boxes, testing and tracing circuits, and following conduits and cable routings—you will only be able to make a blind guess at what to carry in your bid.

Be very careful with notes like this. Visualize what might be needed if the installation were new; carry some new conduit, wiring and a J-box or two. Add a little extra labor for the time it takes the electrician to work with existing systems.

Demo doesn’t mean throw it away

Be careful with demolition notes. These, too, are often vague and nondescript and involve multiple stages of work. Quantify each part of the directed scope.

For example, a common fixture demo note found may read: “Remove existing fixture and retrofit with new dimming ballast, clean and relamp. Reinstall after new ceiling is installed.”

This note lists at least four separate tasks, each of which will occur at different stages of the project. What the note doesn’t list is how the replaced fixture will get connected. Does it get a new flex whip? Do you need new circuitry? What about ceiling wires? Supports? There could be a lot of other work required.

What about the “remove” part? If the fixtures are getting “replaced” at a later stage, then they will need to be stored in a safe place. Handling, protecting and storing these fixtures all requires careful labor, so you shouldn’t simply apply five minutes per fixture. Again, check the specifications. “Protect” could require bubble-wrap, palletizing or even special boxing. Not only would this add to the labor, but it could easily add $5 to $10 per fixture.

With multiple stage instructions like this, it is easy to omit material costs and/or labor. Your estimate could be off by $25 and 25 minutes per fixture location. This could be devastating, especially if there are several hundred fixtures.

Don’t forget the labor factor

Lighting retrofits can be labor-heavy jobs, and you don’t want to be too, well, light. It is common for some fixtures to remain in place during the retrofit process. This might seem simpler and faster than having to demo, store and reinstall them, but don’t get too relaxed. The work is still going to be done on a ladder, scaffolding or a lift. This can add a labor factor to a ballast installation. Also, ceiling heights can vary, and the labor factor increases dramatically when you are retrofitting high-bay fixtures in high ceiling areas, such as warehouses.

Estimating lighting retrofit projects can be very difficult to estimate and even more difficult to build. If you are not careful and bid too aggressively, you may find yourself and your profit lost in the dark.

For related articles on this topic, Stan Shook recommends visiting and reading his December 2009 article, “Controlling the Light,” and February 2008 article, “Estimating Renovation Work.”

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 23 years. Reach him at 707.776.0800 and

About the Author

Stan Shook

Stan Shook was ELECTRICAL CONTRACTOR's estimating columnist from 2005 to 2012. He works as an electrical estimator in California. Read his blog at or contact him directly

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