Welcome back to the Curbed series Learn Something where we discover the story behind an architectural feature common to our city.
From the French word “sun breaker,” this architectural feature's main purpose is to block direct sunlight into windows that would otherwise generate unwanted heat gain inside a building. Similar to a trellis, which make a patio more comfortable by diffusing the light during hot summer days, they are positioned above southern facing windows, so the high summer light is blocked but the low angle of the winter sun is still able to reach inside. There are also other ways to achieve this result in conventional architectural ways, like long overhangs, or deep inset windows.
One advantage of using brise soleils is that they are not usually counted in zoning laws for set backs, allowing a building to maximize the street frontage while not adding much to building costs. A characteristic of modern style, this window element is now seen more in new buildings that are being built in DC, especially in developments that are putting more emphasis on environmental performance as compared to buildings built in the past couple decades.
—Vaclav Malek, architectural designer.