Fairfax County’s assessment records list central air on 6,545 of the 6,569 Oakton homes with a dwelling record, and gas decides what kind. The county shows gas service on 93 percent of detached houses built here in the 1990s and 2000s, and on under a third of those from the 1970s. Without gas, one heat pump usually heats and cools, so its outdoor unit has worked since last fall. With gas, it’s usually a plain air conditioner outside, idle since September.
Attached homes lean further electric: about six in ten Oakton townhouses and seven in ten condo units have no gas on the county’s books. Arrowood and Cherrywood Square along Borge Street, Oakton Village off Jermantown Road, Flint Hill Manor on Granite Creek Lane and Trevor House have none at all, while Concord Village and Wyant Property are gas almost door to door.
Most of those townhouses went up in the 1970s and 80s over a full basement, where the indoor half of the system usually stands and the coil’s water often runs to a floor drain. The condos are one-level flats in garden-style buildings, built between 1974 and 1987, with the air handler in a hall closet and its drain line passing over the flat downstairs.
On the big lots, in Hearthstone Village, Timber Lake, Willow Creek Estates, Hannah Hills and Bridges of Oakton, nearly every house tops 4,000 square feet above ground, and a house that size often runs two systems, the bedroom one with its air handler in the attic. Each is its own tune-up at $99. Where nobody has replaced them, those outdoor units are the builder’s, some past 25 summers.