If you own an older home, chances are it wasn’t designed with modern air conditioning in mind. Many historic and pre-1960s houses were built with boilers, radiators, or baseboard heaters instead of forced-air systems. That means no ducts—and for a long time, that also meant no central AC.
But here’s the truth: ducts aren’t the only way to get whole-home comfort. Thanks to today’s HVAC technology, homeowners have excellent options to cool older homes without tearing down walls or compromising historic charm. In this guide, we’ll look at the best central AC units for homes with no ductwork, break down costs, and help you weigh which solution makes the most sense for your home.
Why Older Homes Often Lack Ductwork
Before diving into solutions, it helps to understand the problem. Older homes typically lack ductwork for three reasons:
-
Construction practices: Homes built before central AC became standard relied on radiators or fireplaces.
-
Tight wall cavities: Plaster walls and small spaces often leave little room for bulky ducts.
-
Preservation concerns: Many homeowners don’t want to disturb original woodwork, plaster, or ceilings.
That doesn’t mean you’re stuck with window units or portable AC. With the right system, you can enjoy efficient whole-home cooling without compromising your home’s structure.
For a starting point, Energy.gov recommends first upgrading insulation, sealing leaks, and improving ventilation. This ensures your new AC doesn’t work harder than necessary.
Best Central AC Options for Homes Without Ductwork
1. Ductless Mini-Split Systems
How they work: A ductless system pairs an outdoor condenser with one or more indoor air handlers. Refrigerant lines connect the two, eliminating the need for ducts.
Why they’re great for older homes:
-
No major renovations required.
-
High efficiency—many models exceed ENERGY STAR® standards.
-
Zoning: you can cool one room or the entire house.
Potential drawbacks:
-
Higher upfront cost per unit compared to window AC.
-
Indoor air handlers are visible, which may not suit every design preference.
Ductless systems are often the top choice for homeowners balancing comfort and efficiency. The ENERGY STAR program notes they can cut cooling costs by up to 30% compared to traditional systems.
2. High-Velocity Central AC Systems
How they work: These systems use small, flexible ducts—about two inches in diameter—that fit through narrow wall spaces. Air is delivered through discreet outlets, making them ideal for retrofits.
Why they’re great for older homes:
-
Preserves architectural features by avoiding bulky ducts.
-
Provides even cooling throughout the home.
-
Runs quietly compared to some traditional systems.
Potential drawbacks:
-
Installation is more complex and requires experienced contractors.
-
Costs can be higher than ductless systems.
ASHRAE highlights high-velocity systems as a practical solution when retrofitting older structures.
3. Packaged Central AC Units
How they work: Unlike split systems, a packaged unit combines the condenser and air handler into one outdoor cabinet.
Why they’re great for older homes:
-
Compact all-in-one design.
-
Easier maintenance with components housed together.
-
Frees up indoor space.
Potential drawbacks:
-
Not always suitable for tight spaces.
-
May require significant modifications to install.
Packaged units can be effective in certain older homes with accessible basements or attics, though they’re less common than ductless or high-velocity setups.
Factors to Consider When Choosing an AC System
Not all solutions fit every home. Here’s what to weigh before deciding:
-
Size and layout: Larger homes may need multi-zone ductless systems or high-velocity setups.
-
Energy efficiency: Look for SEER2 ratings and ENERGY STAR certification. The DOE continues to tighten efficiency standards to help households save.
-
Budget: Ductless units start lower but add up with multiple zones. High-velocity systems have higher upfront costs but work well in large, historic homes.
-
Contractor experience: Older homes require installers who understand preservation and retrofitting challenges.
If you’re comparing different system types, it’s worth looking at the bigger picture. Our guide on the Top 10 Central AC Units Compared shows how efficiency, brand reliability, and upfront costs stack up across today’s most popular models.
Cost and Installation Considerations
Here’s what you can expect to spend on installation:
-
Ductless Mini-Splits: $4,000–$8,000 depending on the number of indoor air handlers.
-
High-Velocity Systems: $8,000–$15,000 due to specialized equipment and labor.
-
Packaged Units: $5,000–$10,000 depending on home layout.
While these numbers may feel steep, efficiency rebates can help. EPA’s ENERGY STAR outlines qualifying systems, while the ACEEE provides updates on incentive programs.
Tip: Check state-specific programs, as many utilities offer rebates for high-efficiency retrofits.
Long-Term Benefits of Ductless and High-Velocity Systems
Beyond immediate comfort, these systems offer lasting value:
-
Energy savings: More efficient operation reduces monthly utility bills.
-
Better comfort: Even cooling without the hot and cold spots common with window units.
-
Improved air quality: No dusty ducts; systems can integrate advanced filters and dehumidifiers.
-
Increased home value: Energy-efficient cooling is attractive to future buyers.
The American Council for an Energy-Efficient Economy notes that homes with high-efficiency systems often sell faster and at higher values due to lower operating costs. Many homeowners are also exploring how cooling integrates with renewable energy—topics we’ll cover more in Central AC Compatibility with Solar Power: What You Need to Know.
Key Takeaways for Homeowners
-
You don’t need ducts to enjoy modern central AC.
-
Ductless mini-splits and high-velocity systems are the most efficient options for older homes.
-
Always weigh upfront investment against long-term comfort and savings.
-
Work with an experienced HVAC professional to ensure proper installation and avoid unnecessary damage to your home’s structure.
Final Thoughts from Alex Lane
Older homes may not have been built with central air conditioning in mind, but that doesn’t mean you’re stuck sweating through the summer. With today’s technology, solutions like ductless mini-splits and high-velocity systems make it possible to enjoy modern comfort without tearing your house apart.
Yes, the upfront cost can be higher compared to a window unit or portable AC, but the trade-off is worth it: lower monthly bills, improved indoor air quality, and a cooling system that adds long-term value to your home.
If you’re considering an upgrade, start by talking to a licensed HVAC contractor who understands older homes. The right system doesn’t just keep you cool—it helps preserve the character of your home while making it more efficient for years to come.
Alex Lane
Your Home Comfort Advocate
