Flickering lights get written off constantly. We hear it all the time โ โoh itโs always done that,โ or โthe landlord said itโs just the ballasts.โ Sometimes thatโs true. Usually it isnโt. And in Sarasota commercial buildings specifically, the underlying causes tend to be things that donโt fix themselves and donโt stay small.
Power drops are the same story. That momentary sag where everything dims for half a second when a piece of equipment kicks on โ business owners learn to live with it. They stop noticing it. And meanwhile, the actual cause is sitting in the wall or the panel doing slow, cumulative damage.
Weโve been inside enough commercial buildings across Sarasota to have a pretty good picture of why this happens here, and itโs worth laying out honestly. Because the answer isnโt always โyou need new fixtures.โ Sometimes itโs something more serious.
It Starts With the Building Itself
Sarasota has a mix of commercial building stock thatโs worth understanding. Thereโs newer construction out in Lakewood Ranch, the east side of town near I-75, and some of the redeveloped corridors around downtown. And then thereโs a substantial amount of older commercial space โ strip centers along the Tamiami Trail, buildings in the Rosemary District, older retail and office stock around Fruitville Road, Beneva, and Bahia Vista โ that was built in the seventies, eighties, and nineties with electrical infrastructure that was sized for what businesses needed then.
What businesses need now is not the same. The electrical demand of a modern commercial space โ the HVAC load alone is heavier, the kitchen equipment has changed, LED retrofits actually draw current differently than the old fluorescent systems, everybodyโs running more computers and more electronics โ it adds up. A building wired for the electrical demand of 1985 isnโt necessarily adequate for a 2024 tenant, and sometimes that mismatch shows itself as flickering lights and voltage drops before it shows up as anything more dramatic.
Thatโs the context. Now letโs talk about specific causes.
Loose Connections Are the Most Common Culprit
If we had to pick the single thing we find most often when we trace flickering lights or power drops in a Sarasota commercial building, itโs loose connections. Not always at the panel โ though thatโs one place โ but anywhere along the circuit path. At outlets. At junction boxes. At the fixture itself. At the breaker terminals.
Connections loosen for a few reasons. Thermal cycling is a big one โ wires expand when they heat up and contract when they cool down, and over years of daily cycles that mechanical movement works connections loose. Sarasotaโs humidity accelerates the corrosion process at connection points, which increases resistance, which generates more heat, which speeds up the whole cycle.
A loose connection behaves electrically like a variable resistor. When the load on that circuit is light, it might not cause any noticeable effect. When the load increases โ more equipment running, peak demand periods โ the voltage drop across that bad connection becomes visible as flickering or dimming.
The reason this matters beyond just being annoying: a loose connection under load generates heat. Real heat, localized at that connection point. Thatโs the mechanism behind most electrical fires in commercial buildings. It doesnโt happen all at once โ itโs a slow process โ but the endpoint is the same.
What Corrosion Does to a Connection
In coastal areas like Siesta Key, Lido Beach, Longboat Key, and anywhere else in the Sarasota area with direct salt air exposure, corrosion at connection points is accelerated compared to inland locations. Weโve opened junction boxes in waterfront commercial buildings and found connections that looked perfectly fine from the outside but had corroded through most of their contact surface. The mechanical connection was still there. The electrical connection was barely functional.
You canโt see this from a light switch. You canโt see it from the panel face. It takes someone opening the right boxes and looking at whatโs actually there.
Overloaded Circuits and Panels
Hereโs a scenario we see regularly in older Sarasota commercial buildings. A business moves in, brings their equipment, maybe adds a few circuits over the years through a renovation or tenant improvement. Another tenant had already done the same thing before them. The panel has grown to accommodate more circuits than it was originally designed for โ sometimes through legitimate upgrades, sometimes through work that was done without permits or proper engineering.
Now the building is running more total load than the service was designed for. Not necessarily all at once โ but at peak times, when the AC is running hard on a July afternoon and the kitchen equipment is all going and the lights are on and the computer systems are up, the service is working at or near its limit.
That shows up as voltage drops. The whole building dims slightly when the AC compressor kicks on. Lights flicker when certain equipment cycles. Itโs not dramatic, but itโs consistent, and itโs telling you something about the relationship between your buildingโs electrical capacity and its actual demand.
This is especially common in restaurant buildings along the Trail or in the downtown Sarasota area where a space gets repurposed over time โ converted from retail to food service, or food service operation that expands its kitchen equipment without a corresponding electrical upgrade. The service that was right for one type of business isnโt necessarily right for the next one.
The HVAC Factor
Commercial HVAC systems in Southwest Florida run harder than almost anywhere else in the country. Weโre talking about systems that cycle frequently, run long hours, and in older buildings are sometimes undersized relative to the actual cooling load.
A struggling HVAC compressor draws more current than a healthy one. When it kicks on, that startup draw is significant โ it can pull enough current to cause a momentary voltage sag on the circuit, and if the circuit shares capacity with lighting, you see a flicker.
More concerning is when an HVAC system thatโs degrading mechanically starts drawing progressively more current to do the same work. That increased load on the electrical system is invisible unless someoneโs measuring it. The electrical panel doesnโt know the compressor is worn โ it just knows the circuit is drawing more amperage. Breakers trip. Connections get more heat. The panel works harder.
We had a call from a property manager for a small office building off Cattlemen Road in Sarasota a while back. Theyโd been chasing a flickering problem in one wing of the building for months. New fixtures, new ballasts, nothing fixed it. When we got out there and actually pulled some measurements, the circuit feeding that wing was running consistently near its rated capacity because of the HVAC unit in that zone. The circuit wasnโt overloaded โ it was just running hot all day, every day, and the cumulative heat at a couple of connection points had degraded them to the point where any additional load showed up as visible flicker. The fix was addressing the connections and right-sizing the circuit for that load. Not buying new fixtures.
Utility Side Issues โ And How to Tell
Not every flicker is inside the building. Floridaโs utility infrastructure handles a substantial load during peak summer months, and voltage variations from the utility side do occur โ especially during or after major storm events, during high-demand periods, and in older distribution areas.
If flickering is happening across the entire building simultaneously, affects multiple unrelated circuits, and correlates with certain times of day or weather conditions, thereโs a real possibility the source is external. FPL and other local utility providers have their own infrastructure maintenance responsibilities, and if the issue is upstream of your meter, itโs not something an electrician inside your building is going to fix.
The way to sort this out is with voltage monitoring. A few days of measured data at the service entrance tells you whether the voltage coming in from the utility is stable. If it is, the problem is internal. If itโs fluctuating, youโve got documentation to take to the utility.
Weโve helped a few Sarasota commercial property owners navigate exactly this process. Getting the utility to acknowledge and address a service quality issue isnโt always fast or easy, but having measured data is what makes it possible. You canโt argue from โthe lights flicker sometimes.โ
Aging Wiring and Insulation
Older buildings have older wire. Thatโs not automatically a crisis โ plenty of commercial buildings in Sarasota that were wired forty years ago have perfectly functional electrical systems today, as long as theyโve been maintained and havenโt been overloaded.
But wiring insulation ages. In Floridaโs heat, the aging process is faster than in cooler climates. Attic spaces in local commercial buildings regularly hit temperatures above 140 degrees in the summer. Wiring that runs through those spaces โ which is common in single-story commercial buildings with flat or low-slope roofs โ accumulates heat stress over decades. The insulation becomes brittle. It can crack. And cracked insulation on a wire thatโs running close to other surfaces is how intermittent faults develop.
An intermittent fault is exactly what it sounds like โ a connection that works sometimes and doesnโt work other times, depending on temperature, load, humidity, or just the particular position of the wire on a given day. It shows up as exactly the kind of inconsistent flickering thatโs hard to trace without thermal imaging or systematic circuit-by-circuit testing.
This is one area where we really do find that older buildings in the Sarasota area โ particularly buildings that havenโt had a professional electrical inspection in years โ have accumulated deferred maintenance thatโs starting to express itself as visible symptoms.
What Business Owners Usually Try First (And Why It Doesnโt Work)
The most common response to flickering lights is replacing the fixtures or the bulbs. If itโs an LED fixture issue โ a driver thatโs failing, a fixture thatโs genuinely incompatible with the dimmer itโs running on โ that might work. But that scenario is a minority of flickering cases.
The second most common response is doing nothing and calling it cosmetic. We understand the impulse. Itโs not causing any obvious problems, the business is running fine, there are bigger things to deal with. But flickering and power drops are symptoms. Symptoms have causes. And the causes in this list โ loose connections generating heat, overloaded circuits, aging insulation โ those causes donโt improve on their own.
The third thing people try is calling an electrician who swaps a breaker or tightens something at the panel and calls it done. That helps if the issue is at the panel. It misses the problem if the issue is downstream โ at a junction box in the ceiling, at a connection inside a conduit run, at an outlet thatโs been worked loose over years of use.
Tracing a real flickering problem takes systematic work, not guesswork.
What a Proper Diagnosis Actually Looks Like
When Coharbor Electric responds to a flickering or power drop call in a Sarasota commercial building, the starting point is always the same: we want to understand the pattern before we start touching things.
Is it one circuit or multiple? Is it consistent or intermittent? Does it correlate with specific equipment cycling? Has it been getting worse? When was the last time the panel was actually opened and looked at by a licensed electrician?
From there itโs a combination of visual inspection, thermal imaging to look for hot spots that arenโt visible to the eye, and load measurements on the circuits involved. Most of the time the source of the problem becomes obvious within a couple hours of systematic work. Occasionally it takes longer, particularly with intermittent faults in older wiring.
What we wonโt do is replace fixtures and call it done when the problem is clearly somewhere else.
If Your Sarasota Building Has This Problem, Letโs Figure Out Whatโs Actually Causing It
Flickering lights and power drops in a commercial building arenโt just nuisances โ theyโre indicators. Something in the electrical system is working harder than it should, or has deteriorated to the point where it canโt do its job reliably anymore.
Coharbor Electric works with commercial properties all across Sarasota, Bradenton, Venice, North Port, Lakewood Ranch, and the surrounding area. Weโve traced these problems in restaurant kitchens, office buildings, retail centers, and waterfront properties, and we know what the common causes look like in this specific environment.
Call Coharbor Electric and let us take a real look. Weโll diagnose whatโs actually happening โ not just treat the visible symptom โ and give you a straight answer about what it takes to fix it. Because a building thatโs flickering today has a reason for it, and that reason is worth finding out.
