THE
Status OF
Gutters
by Sally Zimmerman, Senior Preservation Services Manager
“THEY DON’T MAKE THEM LIKE THEY USED TO.” It’s a cliché often repeated about old houses, but for an owner who wants to preserve the home’s historic construction methods and materials when making repairs, a better turn of phrase might be, “Let’s not make them like we do now.” Even something as a humble as a gutter can present challenges when it comes to repairs or modifications, and it can be hard to find a tradesperson who understands old houses and the techniques of traditional building. Similar to elaborate moldings or a complex bit of timber framing, the lowly gutter has a construction history. Understanding that history can be a first step in knowing how to preserve the look of an old house. 10
Historic New England Fall 2017
Often, houses lacked gutters, but when they were used historically, two basic types were common. One type was hung or attached to the house, the other was built into the roofing system. The typical modern gutter is the first type, a trough hung just below the eave drip line and attached to a flat trim piece (the fascia) at the top of the main volume of the house. Most often, this gutter is aluminum, “seamlessly” created on site by a machine that bends a roll of flat sheet stock into the shape known as a K-style, or ogee. Like the traditional wooden gutter it replaced, the K-style has a flat back and a molded outer profile. Aluminum gutters, along with other aluminum products (including siding), were developed after World War II as the market for this metal shifted from military to civilian applications. Cheap, lightweight, and easy to install, the K-style gutter is practical but easily damaged by snow and ice loads or ladders placed against it. The K-style gutter also often obscures a historic cornice molding, especially when retrofitted to a house that was not originally constructed with a hung gutter. Many eighteenth- and nineteenthcentury houses, particularly those with deep overhanging or elaborately molded eaves aren’t easily fitted with hung gutters. For these houses, water, the archenemy of wooden houses, was directed away using the second type of gutter, the built-in, concealed, or box gutter. One restoration roofer calls the built-in gutter “the most complicated system in the building envelope.” Built-in gutters were constructed to be invisible, allowing the design details at the roofline of the house—a beefy Georgian cornice, or a richly bracketed Italianate eave— to stand proud of clumsy leaders and downspouts. With a built-in gutter, a deep notch is cut into the rafters just above the edge of the roof and a shallow channel, typically lined with metal and sloped toward an outlet drain, is constructed. Rainwater flows into the channel and is captured before reaching the edge of the roof, exiting to leaders and downspouts either placed flush