10 things most homeowners don’t know about their own homeNorthern Virginia, checked at the source: November 2026

Fairfax County puts it plainly: maintaining, repairing and replacing the sewer pipe from your house to the public main is the property owner’s job¹. Fairfax Water owns the meter; the pipe from the meter near the street to the main valve inside your house is part of your plumbing². And federal law makes the gas company tell you, once, in writing, that it does not maintain buried gas pipe on your side of the meter, like a line to a grill, pool heater or detached garage³.

Other counties and cities set their own lines, so ask your water and sewer utility where its part ends.

Every Northern Virginia county posts each home’s record online: year built, living area, bedrooms, baths, basement and its value, plus nearby sales. Fairfax County’s steps: search your address in the real estate assessment database, open Values for past assessments and Neighborhood Sales to compare⁴.

If something is off, there are two steps. First a simpler review with the county’s assessment office, then, if you still disagree, the Board of Equalization. The deadlines are strict: Fairfax County says there are no exceptions⁴.

Radon is a gas you can’t see or smell. It comes up from the ground and can collect in a house, most of all in basements. The U.S. Surgeon General calls indoor radon the second-leading cause of lung cancer in the U.S.⁸

The Fairfax County Health Department says the EPA rates the county’s radon potential as Zone 1, the highest⁸. The Virginia Department of Health says Loudoun should be rated high risk too⁹.

FEMA’s own numbers: people outside high-risk flood zones file more than 20 percent of all claims to the National Flood Insurance Program, and homeowners policies “do not normally cover flood damage”¹⁰.

Flood insurance is not only for homes near the Potomac. Flash floods follow small streams and storm drains, and a new policy usually takes 30 days to start¹⁰.

The Virginia Bureau of Insurance says companies “are required by law to offer you water and sewer back-up coverage”, and that you “may have to pay extra” for it¹¹. Offered is not the same as included. It is a line many owners never look for until a floor drain or sump overflows.

The same guide says a homeowners policy generally does not cover floods or earthquakes¹¹.

Virginia’s Chesapeake Bay rules protect a strip along streams called a Resource Protection Area. In Fairfax County it reaches 100 feet from streams with year-round flow and other water features. Clear-cutting is not allowed, and sheds, gazebos, pools and detached garages generally need an exception after a public hearing. What was there before the rules can stay, but can’t grow¹².

The Bay Act covers Arlington, Fairfax and Prince William counties and the cities of Alexandria, Fairfax and Falls Church. Loudoun County, Manassas and Manassas Park are not on the state’s list¹³.

Virginia 811 says contacting it before you dig “is the LAW”, that there is no set depth before you need to, and that many utilities are buried “just a few inches below the surface”. A new fence, a mailbox, a garden or an old stump all count, and the service is free¹⁴.

One more surprise: 811 marks the public utility lines. Pipes that are yours, like the buried gas line to a grill, are not on its map, and the gas rule says to find them before you dig and dig near them by hand³.

Fairfax County’s permit system, PLUS, can be searched with no account¹⁵. Loudoun’s LandMARC lets anyone search public records such as permits¹⁵. Decks, finished basements, additions and big electrical or plumbing jobs usually leave a record.

If a past owner finished a basement or built a deck without a permit, you want to know before you sell or refinance, not when a buyer asks.

Fairfax County’s 2026 limits: you (or your spouse) are 65 or older, or permanently and totally disabled; household income is $90,000 a year or less; and net assets are $400,000 or less, not counting the home. Relief runs from 100% at $60,000 or less down to 25% at $80,001 to $90,000¹⁶.

Veterans with a 100% service-connected, permanent and total rating pay no real estate tax on the home they live in and up to one acre¹⁷.

Under Virginia’s Property Owners’ Association Act, the association’s books and records are open to a member in good standing, or someone the member authorizes, for a proper purpose. Send a written request: an HOA with a management company has 5 business days, a self-managed one 10. Copy charges can’t be more than the actual cost¹⁸.

That is how owners see the budget, the reserve study and the contracts their dues pay for.