When was the last time you thought about the architectural style of your house? The listing when you bought it said it was a Colonial, but is it really?

When real estate agents list a property with the multiple listing service, they have complete discretion over how to categorize the architectural style of the house.

Sometimes they get it wrong. Official records occasionally get it wrong as well. And often, homeowners themselves aren’t even sure.

But real estate professionals say that knowing your Colonial from your Federal- and Tudor-style home really matters when it comes to buying and selling. That’s because certain styles are more popular than others, and a home’s style can factor into its resale value, agents say.

By far, most area agents say Colonial-style homes have long been the most popular in the Washington area. These are typically brick, two- or three-story homes that feature a gable roof, a front door centered on the house and symmetrical windows spaced on either side. Usually, they are rectangular in shape, with simple detailing; living spaces are on the first floor and bedrooms on the second.

“Why do people want a Colonial? There are many factors that go into determining the price of a house, but one straightforward correlation is that a Colonial is simply a bigger house,” said Betsy Davis, data analyst at Real Estate Business Intelligence.The average square footage for all Colonials sold in the Washington area in 2010 was 2,537. The next largest house style was the split-level, at an average 1,697 square feet. Split-level homes are designed with the floors offset from one another, connected by short stairways.

The three most popular styes in the Washington area are Colonials, ramblers and Cape Cods. These styles represented 70 percent of total area sales in 2010, according to data provided by Metropolitan Regional Information Systems, a local multiple listings service.

Colonials alone account for more than 40 percent of all sales in the Washington area, with an average price of $623,387, according to MRIS data. The average sale price for a split-level home was $419,024, according to the data.

Although Craftsman and Spanish-style homes are fewer in number, MRIS data also found that those styles had high average sale prices, perhaps reflecting more custom home sales.

“You shouldn’t pay a Colonial price for a split foyer” style home, said Jim Warkentin of Keller Williams Realty of McLean. He explained that a split-foyer home is less expensive to construct because it doesn’t require builders to dig a full basement.

The region’s abundance of Colonials, particularly in the District and close-in suburbs, has much to do with timing. Many of the area’s homes were built during World War I and World War II. During that period, “Colonial Revival was the most popular historic revival house style in the United States,” said architecture columnist Jackie Craven.

The Colonial Revival style — essentially, a Colonial-style home that was not built during the Colonial period — followed on the heels of the Victorian style.

During the last part of the 19th century, builders began using a new tool — the jigsaw — to create more detailed designs on home exteriors, making elaborate Victorian-style homes, said architectural historian Kimberly Prothro Williams. The Colonial-style homes that followed evoked a style marked by smaller, less ornate homes “without the Victorian excess considered gaudy by then,” Williams said.

House styles are more than just a how a home is put together. “Architectural styles are representative of a period,” said Williams, National Register coordinator for the D.C. Office of Planning/Historic Preservation Office. Knowing about the architecture of your home “can inform you what was happening at the time and what people were thinking.”

Sometimes learning more about the architecture of your home can result in a kind of structural buried treasure. “Sometimes older houses are completely subsumed by later additions. It’s always an incredible find,” said Williams. This may mean your mid-century modern started as a Victorian, or it may mean uncovering buried elements of earlier styles.

When Williams was summoned to a private home in Annapolis a few years ago, she never dreamed what she would see: a fully preserved roof from the 1700s. Owners who had purchased the Georgian-style home in the mid-1800s had completely covered the old roof with a new one, essentially casing it into a new attic level. “The round butt shingles were completely preserved,” said Williams.

“We were all just blown away. It’s rare to have an 18th-century roof intact with original materials. Most would have had shingles replaced multiple times,” said Williams. Even the people who owned it at the time had no idea what an architectural marvel lay literally under their roof.

In the District, different parts of the city showcase architectural styles that were popular when the houses were constructed. The city’s northwest and northeast quadrants were largely built during the Victorian era, Williams said.

“In Georgetown and on Capitol Hill you see more Federal Era” architecture, she said, which was the most popular style in the late 1700s and early to mid-1800s.

The White House, on which construction began in 1792, is a classic example of Federal architecture with added elements of classical Greek Ionic architecture, such as tall, decorative columns. Federal architecture, also known as Adam, includes elements such as symmetrical windows and doors, and semicircular fanlights, or windows, over paneled front doors.

Other interesting styles found in the District include Gothic Revival, Greek Revival and Art Deco. Lincoln’s Cottage, where the former president and his family lived during periods of the Civil War, is a good example of Gothic Revival, with its steeply pitched roof and decorated gable trim. There are few finer examples of Greek Revival architecture than the Doric-columned Arlington House, where Confederate Gen. Robert E. Lee lived.

One of the District’s best examples of Art Deco is the Kennedy-Warren Apartments building on Connecticut Avenue in Northwest. Its geometric and zigzag patterns are accented by Aztec-style decorative elements such as angular birds.

Many homes built in the past 50 years combine a number of different architectural elements and hint at styles from different periods. “Modern-day homes are often called neo-eclectic,” said architecture columnist Craven. “They are an eclectic mix of details borrowed from many times, places, and building traditions.

For example, it was popular in the late 1960s and early 1970s to place a neoclassical pedimented portico on a rambler, according to Virginia and Lee McAlester, authors of “A Field Guide to American Houses.”

For many homeowners, a house’s architectural style is part of its appeal. Even home buyers who know little about whether a roof is hipped or gabled notice architecture, agents say.

“What I find most in Washington is that buyers don’t buy what they truly want; they buy what they can sell. They know five years down the road they’ll be leaving, and they know they can sell it,” said Roger Carp, branch manager at the Bethesda Avenue Long and Foster office.

Susan Straight is a freelance writer.

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