Round Hill Homes by the Numbers
The town and the countryside around it are two different housing stories: an old town center, and a ZIP code filled mostly by homes built since 1990.
| Measure | Round Hill (town) | ZIP 20141 |
|---|---|---|
| Population | About 680 | About 8,400 |
| Built before 1940 | 30% | 6% |
| Built 1990 to 2019 | About 41% | 77% |
| Heat with propane | 18% | 37% |
| Heat with fuel oil | 14% | 3% |
| Heat with natural gas | 1% | 2% |
Source: U.S. Census Bureau, American Community Survey 2024 5-year estimates. The town's figures come from a small sample and carry wide margins of error.
Heat Pumps, Propane and Oil: What Each Means for Your Ducts
| System | How it uses the ducts | What to check |
|---|---|---|
| Electric heat pump | Long, steady run times in winter and summer | Filter more often, coil and drain pan each spring |
| Propane furnace | Shorter, hotter heating cycles | Yearly service before winter, carbon monoxide alarms |
| Oil furnace | Shorter, hotter heating cycles | Yearly burner service; dark residue at vents needs a look |
The EPA advises having fuel-burning furnaces inspected and serviced before each heating season, and the Consumer Product Safety Commission advises carbon monoxide alarms on every level of the home. Dark marks around vents in an oil-heated home are covered in the black dust guide.
Older Homes in the Town Center
Nearly a third of the homes inside town limits date to before 1940. Central air in those houses was added later, so ducts often run through attics, basements or closets. Before cleaning an older heating system, the EPA advises checking its materials for asbestos, and duct insulation that is wet or moldy gets replaced rather than cleaned.
Newer Homes Around Town
Most of the 20141 ZIP code was built between 1990 and 2019. In houses from the last decade or so, construction dust in the ducts is the more common finding than decades of buildup; the new home duct cleaning page explains how to check for it.
Dryer Vents on Rural Lots
Birds nest in dryer vent hoods, especially ones with a broken or missing flap. A nest blocks the exhaust and adds fuel to the lint. The bird nest and lint removal page covers clearing a hood and the rules for active nests. A cleaning typically costs $135 to $360.
Where Round Hill Is
Round Hill sits at the crossroads of Route 7 and Route 719 (Woodgrove Road) in western Loudoun County, about 21 miles west-northwest of Washington Dulles International Airport. It is its own incorporated town, separate from Dulles and from Leesburg, which lies about 11 miles east along Route 7.
Round Hill Duct and Dryer Vent FAQs
Does duct cleaning work the same with a heat pump?
Yes. The ducts, blower and coil are cleaned the same way. Heat pumps move air for long stretches in both seasons, so filters load faster and the coil and drain pan deserve a check each spring.
Do propane furnaces need carbon monoxide alarms?
Yes. Propane burns like natural gas and produces carbon monoxide. The Consumer Product Safety Commission advises carbon monoxide alarms on every level of the home, and the EPA advises servicing fuel-burning furnaces before each heating season.
How much does dryer vent cleaning cost in Round Hill, VA?
Dryer vent cleaning around Round Hill follows the Northern Virginia range of about $135 to $360. Long runs, roof terminations and nest removal sit at the upper end or are quoted on top.
Is Round Hill part of Dulles?
No. Round Hill is a separate incorporated town in western Loudoun County, about 21 miles west-northwest of Washington Dulles International Airport, at the crossroads of Route 7 and Route 719.