Whole-House Generator Cost: Equipment and Installed Systems

The power goes out, and you start thinking about a generator that will bring the house back on without a trip outside. The price on the generator itself is only the first number you need.

So HVAC Comfort gives $17,000 to $20,000 for an installed whole-home Kohler generator in Michigan. Other installers publish lower starting packages, which makes the equipment, site work and promised coverage worth comparing.

Generac prices have their own guide, so I will compare Kohler and Cummins examples here, explain what an installed quote should cover and show three owners’ different costs. The business pages were checked October 24, 2026.

What Installed Systems Cost at These Businesses

GSHA Services serves northern Chicago suburbs and southeastern Wisconsin. Its prices below are starting packages for straightforward installations, with the final price confirmed after a visit.

The Michigan range comes from HVAC Comfort’s own cost page. It is the range in the price card, rather than a national average or an upper limit for large homes.

Equipment Alone Is a Different Price

UTS Electric Pros’ Dallas page has an RS20A unit price of $5,925.25 beside its $13,500 to $17,000 installed estimate for a typical 20 kW Cummins system.

The installed estimate includes the pad, transfer switch, permit and commissioning, with the gas line included as its own line item. The difference between those prices is not simply an electrician’s labor bill.

If you supply the generator yourself, first agree on who supplies the transfer equipment and who takes responsibility for startup and warranty registration.

What Does “Whole House” Need to Mean?

You may want the refrigerator, well pump and a few rooms working, or you may want to use the kitchen and central air as usual. Those are different requests, even at the same address.

Kohler’s sizing guidance bases capacity on the electrical load and a professional assessment. The dealer should account for starting and running power, rather than choosing by floor area alone.

Ask which appliances can run together and whether the design uses load management to keep demand within the generator’s capacity. Have that operating plan included with the proposed model.

Fuel also changes the rating. GSHA’s table gives the 20RCA as 18 kW on natural gas and 20 kW on propane; the 26RCA is 24 kW on natural gas and 26 kW on propane.

That is why I would ask for the rating on the fuel actually available at your house. A larger number in the model description does not promise that output with every fuel.

The Work Around the Generator

GSHA’s package includes a pad, automatic transfer switch, standard gas and electrical work, permits, inspection and startup. Gas-line distance, a meter upgrade and permit costs can change its final estimate.

Walk the proposed location with the contractor, and ask them to point out the fuel route, the electrical route and any trenching or yard repairs, so those jobs do not appear as a surprise after the deposit.

Have the installer separate utility work from its own work and name who schedules each part. A meter upgrade or another contractor’s connection needs a place in the project total.

What Owners Spent on Different Parts of the Job

These US forum accounts are useful because they describe different purchases. None should be treated as a complete current dealer package for your house.

• padroo in Chesterton, Indiana had over $8,000 in a Kohler project, posted January 13, 2017. The owner did substantial installation work and described a larger gas meter and a dealer check before startup.
• Whaledriver in Colorado recalled about $10,000 to get a standby option wired and plumbed, posted January 18, 2024. The post does not itemize that option’s equipment or work; the owner chose a portable setup instead.
• Fullfan in northwest Pennsylvania paid $1,100 for a Kohler technician’s installation, posted January 19, 2024. This was an installation charge for an owned 20 kW unit, not the generator purchase price.

The Indiana owner installed the system almost three years before that 2017 post. Fullfan had owned the Kohler for just under two years when posting in 2024.

Plan the Handover and the Ongoing Cost

Before the final payment, ask for the startup results, transfer demonstration, warranty paperwork and maintenance schedule. You should know who to contact if the system fails its exercise cycle or does not start in an outage.

Fuel and maintenance belong beside the purchase budget. Have the dealer quote service separately and give fuel consumption for the proposed model at the loads you expect to use.

I would choose the contractor after comparing the operating plan, included work and service support. The lowest equipment price alone cannot tell you what the finished backup system will cost.

Questions About Whole-House Generator Prices

Where These Prices Come From

Installer and manufacturer pages checked October 24, 2026. The owner accounts are dated 2017 and 2024.

• HVAC Comfort: Michigan installed Kohler range.
• GSHA Services: model starting prices, fuel ratings and inclusions.
• UTS Electric Pros / Clements Electric: Dallas Cummins equipment and installed estimates.
• Kohler: generator sizing.
• Garage Journal: Indiana project and Rokslide: Colorado and Pennsylvania accounts.

I hope this helps you budget for the backup power you want. If you have a recent US installation quote to share, you can reach me at costcheckr@gmail.com.