A home Generac generator typically costs $12,000–$20,000 installed, depending on the house size and total power needs. For homeowners researching how much does it cost to have a Generac generator installed, the final price will vary based on the electrical panel capacity, fuel type, and site conditions.
Labor, permits, and any required system upgrades also affect the total installation cost. Grounded Electric evaluates these factors before providing an estimate to ensure safe, reliable backup power. Homeowners can review our complete generator guide for a deeper overview of system planning.
Key Takeaways
- Most Generac systems cost between $12,000 and $20,000 to install, though prices vary based on size and site requirements.
- Panel upgrades, permits, and gas line work raise the total cost to install a standby unit.
- A load check helps prevent buying a unit that is too small for backup power.
- Service and fuel use affect the full cost of a Generac generator installation over time.
Generac Installation Cost Breakdown
Equipment and Installation Costs
Generator price depends on how much power it can produce. A home Generac generator costs $12,000–$20,000 when fully installed, and the total can vary based on generator size and site conditions. Larger homes with higher power demand will fall toward the upper end of the range.
What Increases the Total Cost
Several items can raise the cost of a Generac generator installation:
- Upgrading the main electrical panel
- Extending or resizing a natural gas line
- Permit and inspection fees
- Trenching or pad work
Homes that require electrical panel upgrades or additional circuit space will typically incur higher installation costs. Local labor rates and inspection rules can vary by region.
What Is Included in a Standard Installation?
A standby system connects to the home’s electrical panel and fuel line. The work includes setting up the unit, installing the transfer switch, connecting wiring, grounding the system, and testing it. These steps ensure the backup generator works safely during outages.
Grounded Electric is Generac Certified and follows the maker’s setup rules. This helps ensure the unit operates as designed and complies with code standards.

Electrical Code and Safety Compliance
Standby systems must comply with the National Electrical Code. These rules cover grounding, bonding, and the setup of safe transfer switches within the electrical panel. Proper bonding stops dangerous backfeed during outages.
Fuel supply must meet pressure needs, especially for natural gas systems. Robert “Bobby” Mulholland checks both electrical and gas systems before inspection. Code compliance protects the home and ensures reliable backup power.
Whole House Generator Cost Calculator
A whole-house generator cost calculator helps estimate how much power your home needs, and homeowners can use our generator wattage calculator for a quick starting estimate. You add loads such as HVAC units, refrigerators, lights, and sump pumps, and homeowners can use our generator wattage calculator for a quick starting estimate.
Each item has start and run watt needs, which can be reviewed in a detailed generator wattage chart to better estimate total demand.
Online tools give rough numbers. A licensed electrician confirms electrical panel capacity and natural gas supply before final sizing. Barret Abramow, Project Manager and Co-Owner, helps coordinate these checks for safe installation planning.
How Long Does Generac Installation Take?
Most installs take one to three days after permits are approved. Work includes installing the unit, wiring it to the electrical panel, and connecting the fuel lines. Final testing may happen on a separate day.
Permits can take weeks to be issued before installation of the house generator can begin. Weather and inspection delays can add time. Good planning helps reduce wait times and keeps the project on track.
Long-Term Ownership Costs
Standby systems need yearly service. This includes oil changes, filter swaps, battery checks, and test runs. Annual service usually costs a few hundred dollars.
Fuel use depends on unit size and outage length. Systems that run on natural gas pull fuel from the main line. Fuel cost will vary based on run time and local rates.
Is a Generac Generator Worth It?
A standby backup generator restores power fast during outages. Homes in storm-prone areas or with medical equipment benefit most from steady backup power, especially during severe weather events discussed in our guide to the best generator for hurricane season. Value can vary based on the frequency of outages.

When evaluating the cost of installing a Generac generator, many homeowners consider safety and ease of use, and may also explore whether the investment makes sense in our article on are Generac generators worth it.
Working with licensed electricians and trusted Generac dealers helps ensure proper installation of a home generator and long-term reliability.
How to Get an Accurate Installation Quote
A licensed electrician checks the electrical panel, grounding system, and fuel supply. Load tests confirm the right unit size and prevent overload. These steps ensure a safe and code-compliant setup.
A full site visit provides the clearest picture of the total cost. It confirms the true cost of a Generac generator installation before work begins.
If you are considering a standby system, a professional evaluation is the first step. A licensed electrician can review your electrical panel, fuel supply, and power needs to determine the correct generator size and installation plan. Scheduling an on-site assessment helps clarify the true cost to install and ensures safe, code-compliant backup power for your home.
If you are considering a standby system, a professional evaluation is the first step. A licensed electrician can review your electrical panel, fuel supply, and power needs to determine the correct generator size and installation plan. Scheduling an on-site assessment helps clarify the true cost to install and ensures safe, code-compliant backup power for your home.
