By Nancy E. Berry

The skylights at Monticello, including the one in Thomas Jefferson's bedroom, operated on a counterweight system. All 13 skylights have been restored to original function. Photo Courtesy of Monticello/Thomas Jefferson Foundation.

Whether I retire to bed early or late," wrote Thomas Jefferson, "I rise with the sun." Jefferson did get up at dawn each day because his bedroom at Monticello had a skylight in the center of the ceiling. In fact, the use of natural light pervades this famous house. In the late 18th century, Jefferson was one of the first architects in this country to incorporate skylights-a total of 13—into his home. Skylights have been added to residential rooftops ever since for light, ventilation, and even roof access in case of chimney fires. We'll look at three centuries of America's historic skylights and what you need to know about historically appropriate types when planning to introduce one to your old-house roof.

Revolutionary Roof Windows
Often called roof windows, early skylights were wood framed—constructed much like a window sash—typically 3Ç x 3Ç with three courses of glass panes that lapped anywhere from 3/4" to 2 1/2" at the bottom. Muntins were placed vertically so the rain could wash over the glass and not pool.

Metal skylight designs from the 1890s

Many of America's 18th-century classical houses incorporated skylights not only for the practical purposes of admitting air and light, but also to serve aesthetic or stylistic needs. Jefferson was enamored with the idea of rooms awash in natural light. In order to determine the amount of light needed in a space, he would calculate the volume of the room and take the square root of that number. This would tell Jefferson how much square footage of window openings he needed—which included skylights. All of the skylights at Monticello opened with a counterweight system. Today they have been restored to their original condition.

Boston architect Charles Bulfinch also included skylights in the roofs of his Federal-style town houses. Although a few original examples still exist, many of these early wooden skylights could not stand up to centuries of snow, rain, and wind, and have been lost through neglect or renovations.

Victorian Metal
With sheet-metal shops popping up in every major U. S. city in the Victorian era, metal skylights became a standard roof feature on row houses, offering much needed daylight to enclosed stairwells decades before electricity. In its 1890 catalog, Bickelhoupt Sky-light Works advised that homeowners should replace their old wooden skylights with metal. Copper, galvanized steel, and wrought iron manufactured in myriad shapes—hipped, domed, and gabled—were commonly used on flat roofs, while flat skylights were placed on sloped roof surfaces.

Companies also offered custom skylights fabricated to a builder's specifications. Glass was typically fluted or rough, 1/8" to 1" thick, and embedded with wire to guard against falling branches, fruit, or hail. Many of these skylights were operable and also had vents. On steamy days, these vents allowed air to escape through the roof. Vents were equally important in winter months as one 1900 company noted, describing its skylights as "snow and water tight while admitting an escape for condensation in every case." Metal skylights were always set up on curbs (low walls built around a roof opening) that helped keep snow off the glass. By the 1910s skylights, increasingly mass-produced and sold by catalog, crowned many city dwellings.

Kaleidoscope of Color
In high-style houses of the 1880s, it was often fashionable to adorn ceilings with domed or oval panels of leaded-stained glass, often in an entry hall for dramatic effect. Some of the most noted stained-glass designers of the time created glorious skylights for upscale city houses-Louis Comfort Tiffany with naturalistic features, John LaFarge with linear Gothic motifs, and Charles Connick with Renaissance themes, to name just a few. Because leaded-stained glass cannot withstand weather in a horizontal position, these panels were always protected under a skylight or rooftop monitor that diffused the natural light into the house and spared the leaded glass from the elements. Frank Lloyd Wright also used stained-glass skylights in his houses. He designed entire ceilings in earth-toned geometric patterns of glass that cast subdued light throughout the living space.

Proper Placement
If you plan on adding a skylight to your old house, remember that it should blend in with the historic character of the roof, not compete with it. If a skylight did not exist originally, locate the new installation in an unobtrusive spot on the roof, typically on the secondary elevation or rear of the house, according to the National Park Service preservation guidelines. This limits the impact on the house's historic character. If you suspect that a skylight did exist on the house, check your attic ceiling for any ghosts of skylights past, such as rectangular patching in your roof's sheathing. Many skylights have been covered over, and finding an original location could help you decide where to install a new one.

Reproductions
Today there are several companies reproducing wood, metal, or stained-glass skylights that are appropriate for old houses. Pella Windows offers a wood-framed skylight rated for thermal efficiency. Although it doesn't stylistically replicate the roof windows of Jefferson's time, this skylight is an alternative to acrylic domes that notoriously leak.

Charles River Restoration in Hopkinton, Massachusetts, specializes in repairing, restoring, and reproducing metal skylights for Victorian-era and early 20th-century houses. Although much of owner Peter Hosmer's work focuses on reglazing or replacing parts for old row-house skylights, he has a treasure trove of antique sheet-metal catalogs to help him reproduce old patterns. He uses individual 18"-wide panes between copper cames. Unlike window makers of the past, he employs panes of insulated glass in his New England projects due to today's energy codes.

Peter Morava of Morava Studios in Oak Park, Illinois, specializes in Prairie-style and Arts & Crafts designs in stained glass for both windows and skylights. Morava has worked on several Frank Lloyd Wright restoration projects in the Chicago area. The Lyn Hovey Studio in Boston also specializes in restoration as well as new commissions. The studio has recently completed restoring the Tiffany skylight at the Ayer Mansion in Boston.

The Sky's the Limit
Before your contractor cuts into your roof, consider these points.

Restore Media, LLC, is the producer of the
Traditional Building Exhibition and Conference and the publisher of Old-House Journal, Old-House Journal's New Old House, Old-House Journal's Restoration Directory, Old-House Journal's Traditional Products, Clem Labine's Traditional Building, Clem Labine's Period Homes, and tradweb—the Directory of Custom Building and Restoration Services.
Copyright 2007. Restore Media, LLC. All Rights Reserved.