Florida generator guide

Why Square Footage Is the Wrong Way to Size Your Standby Generator

Two houses on the same street, same builder, same square footage down to the closet. One needs a generator about the size of a chest freezer. The neighbor needs one two sizes bigger. So why does the person writing your quote keep asking how many square feet you've got? Because your floor space is easy to measure and your electrical panel is a pain, and that shortcut is exactly how people end up overpaying for a machine they'll never load, or buying one that stalls the first hot night.

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Your generator counts watts, not floors

Here's the thing a generator never asks: how big is your house. It only cares what you switch on at the same moment. Square footage is a stand-in for that, and it's a weak one.

Picture those two identical houses again. One heats with gas and makes its hot water with gas. The other does all of it with electricity. Same roofline, same room count, but on a cold January morning the all-electric house is pulling power the gas house never touches. Measure the floor and they look like twins. Measure the load and they're nowhere near each other.

So the question that actually sizes your generator isn't how many square feet. It's what runs when the lights go out, and how much of it runs at once.

The number that decides it lasts about half a second

Walk out to your air conditioner and you'll meet the real culprit. When that compressor kicks on, it doesn't ease into it. It grabs a huge gulp of power for a blink, several times what it needs to actually keep running, then drops down and hums along on a fraction of it.

That blink is the whole game. A generator that could carry your house all day will still choke and cut out on that half-second lunge if it's undersized for the surge. And square footage tells you exactly nothing about it. A tight little house with a five-ton unit throws a harder punch than a rambling one with a modest system.

So when someone sizes your generator off the roofline, they're guessing at the one number that matters most, from the least useful place there is to guess.

Two small tricks can change the whole answer

Once you're sizing by loads instead of floors, two things flip the math.

The first is a soft start, a small add-on for your AC that takes that violent startup gulp and stretches it into a gentle sip. Homeowners who bolt one on watch the startup draw fall off a cliff, one measured his compressor's inrush drop from the high fifties in amps to under twenty. Suddenly a smaller generator can swallow the same air conditioner without breaking a sweat.

The second is a load-management module. Think of it as a bouncer at the door of your generator. When too many big things try to run at once, it quietly steps the air conditioner aside for a few minutes, lets the oven or the well pump finish, then waves the AC back in, usually before you've noticed it left. That one box can let a right-sized generator cover a whole house that a rule-of-thumb quote would've said needs a much bigger machine.

Which is the part the square-footage math never sees. The right generator is the one that carries what you actually run on the worst night of the year: you, standing in the kitchen, wanting the AC and the fridge and the coffee maker all going at the same time, and getting them. Bigger than that is just money parked in the side yard.

So what size do you actually need?

This is where the roof-measuring falls apart for good. Your answer lives in your panel, your appliances, the tonnage of your AC, whether you cook and heat with gas or electricity, and how much of that you want running when the grid quits. Two of your neighbors will get two different answers, and both can be right.

That's what GENERasic reads. Instead of a watts-per-square-foot shortcut off your roofline, it looks at your real loads and your specific address, your AC, your fuel, your panel, the way Florida storms hit your particular street, and comes back with one installed price. A single committed number for your home, locked before anyone shows up, sized to what you really run.

Punch in your address and see your price. If the size surprises you, now you know why the square footage never could have told you.

Common questions

Should I put a soft start kit on my AC, and will it hurt the compressor?

A soft start cuts the compressor's startup surge dramatically, which is often what lets a smaller generator run your AC without stalling. Some installers worry a cheap or mismatched one can stress a compressor over time, and that's fair, so the fix is a quality unit matched to your specific system by someone who installs them regularly. It's a sizing tool you add when the math needs it, not a box every home has to buy.

Can a smaller generator really run my whole house if it has load management?

Within reason, yes. A load-management module sheds your biggest loads, usually the air conditioner, for a few minutes when the generator gets close to its limit, then brings them back once things settle. People run surprisingly modest generators on serious whole-home loads this way. You're trading 'absolutely everything at the same instant' for a smaller, less expensive machine that cycles the heavy stuff. Whether that trade fits you depends on how much you're willing to let take turns.

Natural gas or propane, and will I run out during a long hurricane outage?

Natural gas from the street doesn't run dry, which is its big advantage in a multi-week outage. The catch is that the same generator makes a little less power on natural gas than on propane, so it's rated lower on gas. Propane gives you more power and works where there's no gas line, but a buried tank has to be refilled, and after a major hurricane the propane trucks can be impossible to get for a couple of weeks. Which one wins really does come down to your street.

Is a bigger generator just safer? Should I size up to be sure?

Not automatically. An oversized unit costs more up front, burns more fuel, and spends most of its life loafing at a fraction of its capacity, which isn't good for it either. What you want is a bit of headroom, not a giant. A right-sized generator with a load module usually beats a sized-up-to-be-safe one on price, fuel, and longevity.

Does the generator have to sit far from my AC condenser? Will exhaust get pulled into the house?

This one trips a lot of people up. Your central AC condenser doesn't draw outside air into your home, only sealed refrigerant lines run indoors, so it isn't sucking generator exhaust inside. There are still real clearance and code rules for where a generator can sit near windows, doors, and equipment, and getting those right is part of what a proper on-site look figures out.

Stop reading ranges. Get your number.

GENERasic pulls the real property, flood, and elevation data for your exact address and returns one all-in installed price — sized to your home, your fuel, and your flood elevation. The vetted local installer confirms it on site.

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