August 22, 2017

Busted: 3 Myths About Heating and Cooling Historic Homes

  • By: Carson Bear

As many historic homeowners know, nothing presents a challenge quite like heating and cooling old homes. Between high costs, low efficiency, and installation projects that threaten to damage the integrity of historic homes, even the most seasoned preservationist has to struggle to retrofit a central air system into an old house. Right?

Well, not necessarily. Small-duct central air systems are one way to help heat and cool old homes more efficiently and effectively than conventional systems. Unico, a 15-year partner of the National Trust for Historic Preservation, helps us debunk three myths about installing central air in historic homes.

Myth: Central air and heating requires lots of ductwork and large installations that ruin the integrity of historic homes.

Unico and other small-duct systems rely on compact air handlers (the part of an A/C system that connects to the ductwork) that are small enough to be installed in tiny spaces like a closet or an attic, rather than large spaces like basements. Unico’s ductwork also has one-third the surface area of conventional ducting, which saves space and can be installed with minimal disruption to historic homes’ walls. Outlets in individual rooms are about the size of a CD and can be designed to blend in seamlessly with ceilings and floors. Additionally, the Unico System only takes between one and two days to be installed; conventional heating and cooling systems can take weeks.

Wausau Prairie School Mansion - Winter

photo by: GEM Team Coldwell Banker Action

It can be especially difficult to heat drafty old homes in the winter.

Myth: It’s impossible to properly heat and cool drafty old homes using central air systems.

Many old homes are not properly insulated, which means that air from central cooling systems can leak out of them easily. While they can't stop all air leakage in the home, small-duct systems like Unico can help ensure that individual rooms are cooled more evenly than conventional systems.

Why? Unico uses a high-velocity system to blow air through flexible, insulated tubes. The air travels through less ductwork more quickly and is able to blow through a room, or an entire house, at an even temperature. Temperatures vary between 5 and 8 degrees in homes that use conventional cooling and heating systems, but temperatures in homes cooled and heated with Unico only vary by 1 to 2 degrees.

Conventional systems lose air that Unico’s supply vents, which are wrapped with insulation and an outer vapor barrier to keep more thermal energy within the ducts, tend to save. Conventional systems lose 20 to 25 percent of their air from duct leaks, while small-duct systems like Unico lose close to zero percent of their conditioned air.

Myth: Between maintenance, installation, and inefficiency, heating and cooling a historic home with central air will never be worth the expense.

Small-duct systems require less installation time and effort than conventional heating systems, so they don’t require additional contractors to help tear out walls, floors, and ceilings to heat and cool old homes. Since these small-duct systems leak almost zero percent of their conditioned air, they are more energy- and cost-efficient than conventional systems throughout their lifespan. (Unico is rated to last 26 years, while the industry standard is between 10 and 15.)

What’s more, the high-velocity air pumping out of the Unico System doesn’t require any professional duct cleaning like a conventional system would; the only routine maintenance these systems need is the occasional changed filter, which homeowners can do on their own.

Small-duct systems bust plenty of the myths surrounding heating and cooling old houses. Compared to conventional air systems, they tend to be unobtrusive, tasteful, and energy efficient—and they help homeowners get more value out of an investment that doesn’t harm their historic homes.

Learn more about the benefits of the small-duct Unico System.

Carson Bear

Carson Bear was an Editorial Coordinator at the National Trust. She’s passionate about combining popular culture with historic places, and loves her 200-year-old childhood farmhouse in Pennsylvania.

This May, our Preservation Month theme is “People Saving Places” to shine the spotlight on everyone doing the work of saving places—in big ways and small—and inspiring others to do the same!