St. Louis homeowners know power outages. Severe summer thunderstorms, winter ice storms, and the occasional derecho have a way of reminding you how dependent modern life is on electricity. A whole-house standby generator solves this permanently — it kicks on automatically within seconds of a power failure and runs on natural gas or propane, so there's no refueling and no manual startup.
Whole-House Generator Cost in St. Louis
| Generator Size | Best For | Total Installed Cost |
|---|---|---|
| 11–14 kW | Essential circuits only (lights, fridge, HVAC) | $5,000 – $8,000 |
| 16–20 kW | Most St. Louis homes up to 2,500 sq ft | $7,000 – $12,000 |
| 22–26 kW | Larger homes, whole-home coverage | $10,000 – $16,000 |
| 36+ kW | Large homes, home offices, well pumps | $14,000 – $22,000+ |
Prices include the generator unit, automatic transfer switch, concrete pad, gas line connection, and electrical installation. Permits and inspection are included in our quotes.
Generac vs. Kohler: Which Should You Choose?
Generac
Generac is the most widely installed home standby generator brand in the US. They offer a broad range of sizes, competitive pricing, and a large network of service technicians in the St. Louis area. Their mobile link monitoring app lets you check your generator's status remotely. Most of our residential generator installations use Generac.
Kohler
Kohler generators are known for premium build quality and quieter operation. They're often preferred for higher-end homes or where noise is a concern. Kohler's transfer switch technology is also well-regarded. Generally 10–20% more expensive than comparable Generac units.
💡 For most St. Louis homeowners: A 20kW Generac on natural gas is the sweet spot — enough to run your entire home including central AC, refrigerator, lights, and devices, with room to spare.
What's Included in Installation
- Generator unit (Generac or Kohler)
- Automatic transfer switch — switches to generator power within seconds of outage
- Concrete or composite pad for the unit
- Gas line connection to your home's natural gas supply
- Electrical connections and load calculation
- Permits with St. Louis County, Jefferson County, or St. Charles County
- Ameren Missouri coordination if required
- Test run and walkthrough
Natural Gas vs. Propane
Most St. Louis homes have natural gas service — making natural gas generators the default choice. Natural gas generators don't require fuel delivery or storage tanks and can run indefinitely during an outage. If your home doesn't have natural gas, a propane generator with a buried tank is a reliable alternative. We install both.
How Long Does Installation Take?
A typical whole-house generator installation in St. Louis takes one to two days. Concrete pad curing adds another day before the unit can be placed. We handle the entire process — from load calculation and permit to final inspection and startup.
Call (314) 408-5647 for a free generator installation estimate. We serve all St. Louis metro communities.