Generator installation questions, answered straight.

HomeAdvisor's 2026 data puts a 20 to 24 kW unit at $5,000 to $6,500 for the equipment, with installation labor of $1,500 to $5,000 on top, plus permits, a pad and fuel piping (HomeAdvisor, updated June 19, 2026). Larger whole-home units (26 to 48 kW) run $6,500 to $21,000 for the equipment alone. Your number depends mostly on generator size, the distance from the unit to the gas meter and electrical panel, and whether the gas meter or electrical service needs an upgrade.

Most single-AC homes of 2,000 to 3,000 square feet land at 20 to 26 kW when the AC and large appliances are load-managed. Two AC systems, a heat pump with electric backup strips, or an all-electric house push it into the 26 to 48 kW range. A load calculation from your panel and AC nameplates decides it. Our sizing calculator gives a starting range.

The on-site work for a home standby generator is usually 1 to 3 days. The calendar time from signed proposal to running generator is typically several weeks, set by permit review, the gas utility confirming or upgrading the meter, equipment availability and the inspection date. Your proposal comes with a dated schedule.

Yes, almost everywhere in the US. A permanently installed generator needs an electrical permit for the transfer switch and wiring, and usually a mechanical or plumbing permit for the gas or propane line. Some cities also review placement and setbacks, and many HOAs want an application first. The installing contractor pulls the permits; you shouldn't have to.

If natural gas is on the street, use it: no tank, no deliveries, and run time is limited only by the utility supply. The catch is volume. A 22 kW air-cooled unit can burn roughly 300 cubic feet of gas per hour at full load, more than some residential meters are set for, so the gas utility has to confirm the meter. Propane works anywhere but needs a tank sized for how long you want to run.

It depends on the unit's listing. Many air-cooled home units are tested and listed to sit 18 inches from the wall, but they still need 5 feet from windows, doors, vents and other openings, plus front access for service. Liquid-cooled and commercial units usually need more. The manufacturer's installation manual and NFPA 37 set the numbers, and local code can add to them.

For a standby generator that starts on its own, yes. The automatic transfer switch watches utility voltage, starts the generator, and moves your loads over, while keeping the generator from backfeeding the utility lines. Under NEC 702.4, an automatic system has to be sized for the full load it can transfer, or use load management that sheds big loads like the AC. More on transfer switch installation.

In most places, no. The transfer switch ties into your service equipment and the fuel line is gas piping, so both need licensed work and inspection. Many manufacturers also require installation by a qualified installer to keep the full warranty.

Yes, if it's sized for it. Starting current is the hard part, not running load: a compressor can pull several times its running amps for a moment. A soft-start kit on the AC, load management in the transfer switch, or a larger unit solves it. We size from your AC nameplate, not a guess.

On natural gas, as long as the utility gas supply holds, with stops for oil checks on long outages per the manufacturer's manual. On propane, it depends on tank size and load. A 500-gallon tank holds about 400 usable gallons at the standard 80 percent fill, which carries a typical whole-home load for several days. Your proposal shows the math for your tank and unit.

Most air-cooled home units are rated in the low-to-mid 60s dBA at 7 meters under normal operation, and the weekly exercise cycle runs quieter at reduced speed on many models. Check the exact model's spec sheet, and your town's noise rules if the unit sits near a property line.

An annual service at minimum: oil and filter, air filter, spark plugs, battery load test, valve and firmware checks per the manufacturer's schedule, and a look at the transfer switch. The unit exercises itself weekly or biweekly so problems show up before an outage does.

Many do. Covenants often cover placement, screening and noise. Get the HOA's form early, since approval can take longer than the permit. We provide the spec sheet and site sketch most HOAs ask for.

A select contractor in our network who specializes in generators: licensed in your state, insured, trained on the equipment they install, and running their own service department. Generator Install Co. handles the sizing, the itemized proposal, permits and scheduling. Your contractor and their license numbers are on the proposal before you sign, and the same contractor services the unit after startup. If we don't have a contractor covering your ZIP code yet, we tell you up front instead of passing your information around.

When the generator serves emergency or legally required loads under NEC Articles 700 or 701, the local authority will usually enforce NFPA 110: Level 1 or Level 2 classification, a 10-second start for emergency systems, a fuel supply rated for the required hours, and monthly testing under load. Optional standby systems under NEC 702 for business continuity usually aren't held to it, though many owners follow it anyway.