ABCs of Architecture

Arcade

A series of arches carried by columns or piers or a covered walkway that provides access to adjacent shops. When supporting weight above, an arcade gains strength from the lateral thrusts of its arches. The example illustrated shows a modern take on the arcade with branched, precast concrete pillars.

Bargeboard

Exposed board running underneath the slopes of a projecting gable roof. Often richly decorated with carved, cut-out, or painted patterns, they are a common feature of houses built in the Gothic Revival and Tudor Revival styles. In some cases, they imitate tracery traditionally carved in stone.

Cupola

From the Italian word for dome, a small structure that sits at the roof ridge designed to bring light and air into dark attic spaces. Large cupolas, such as those used in grand 19th-century Italianate houses, including the one pictured here, can feature windows and occupiable space inside.

Dormer

A vertical window that projects from a sloping roof to illuminate an interior space, often a bedroom, or increase usable space in a loft or attic. Derived from the Latin dormitorium or “sleeping room,” dormers have been used in Northern European domestic architecture since the medieval period and have evolved to complement a variety of building types and architectural styles.

Egg and Dart

An ornamental architectural molding consisting of alternating ovolo, or egg-shaped object, and V-shaped element, such as an arrow or dart. This decorative feature is used on interior and exterior trim and can be made of wood, stone, plaster, or other materials. First employed in ancient Greek temples built in the Ionic style, such as the Erechtheion, it has been utilized extensively in classical architecture ever since.

Grotesque

A carved mythical or monstrous creature used for decorative purposes in architecture. Grotesques are sometimes referred to as gargoyles, which are more accurately decorated spouts used to move water away from the sides of buildings. Medieval cathedrals typically feature these fanciful carvings. One can also find them adorning many Collegiate Gothic buildings on the Yale campus.

Half-Timber

Structures built with timber framing with interstitial wall spaces filled with plaster or brick. Typical of vernacular architecture built throughout Northern Europe since the medieval period, half-timbering regained popularity in the second half of the 19th century with the rise of the Arts and Crafts movement. In the United States, Tudor Revival houses commonly feature half-timbering with plaster, stone, or patterned brick infill.

Ionic

One of the three orders of classical Greek architecture, along with Doric and Corinthian. Each order defines the proportions, ornament, and arrangement of a building and features a distinct type of columnar support. The Doric column, for example, is relatively squat with a simple capital composed of a rectangular abacus and conical echinus, while the Corinthian column is thinner with an elaborate capital covered in stylized acanthus leaves. Falling between these, the Ionic column is somewhat slender with a capital adorned with spiraling volutes. According to the ancient author Vitruvius, Doric and Ionic columns conformed to the proportions of a man and woman respectively.

Jetty

A projecting part of a building, such as a bay window or the upper story of a timber house. Historically, jetties were used in medieval timber-frame buildings as a method of increasing the space of the upper floor without obstructing the street. The most common use of jetties in the United States is in the colonial garrison house, and it can be seen in Colonial Revival examples throughout the country, including the one in East Shore illustrated here.

Keystone

A wedge-shaped stone at the apex of a masonry arch. It is the final piece set during construction and locks all the stones in place, allowing the arch to bear weight after wooden centering is removed. As a symbol of strength and good design, keystones are also often placed atop rectangular doors and windows where they typically serve no structural purpose.

Landmark

A recognizable natural or artificial feature used for navigation, in the world of historic preservation, the word carries much more weight. A National Historic Landmark (NHL) can be a building, district, object, site, or structure that is officially recognized by the US government for its outstanding historical significance. National Historic Landmarks began being designated in 1935 with the passing of the Historic Sites Act. In 1966, with the passage of the National Historic Preservation Act, previously designated Landmarks became part of the new National Register of Historic Places. New Haven is home to 11 National Historic Landmarks, the oldest of which is the 18th-century Connecticut Hall.

Mansard Roof

A four-sided, gambrel roof with a steeply angled lower portion often adorned with dormer windows. Popularized by architect Francois Mansart in 17th-century Paris, the steep roof allowed for a full additional floor of living space above the cornice line. Mansard roofs are now commonly associated with the French Second Empire style, though they may be found in other styles of building.

Niche

A recess set into a wall used for decorative purposes or the display objects. Niches can be found in structures built across the globe since antiquity and not exclusive to any one kind of architecture, as evidenced by the simple recesses seen here, framed with rusticated stones.

Onion Dome

A bulbous dome whose shape resembles an onion, often associated with Russian and Eastern European architecture. Onion domes are popularly believed to symbolize burning candles and are often constructed in groups of three or five, representing the Holy Trinity or Christ and the Four Evangelists, respectively. The example illustrated here is a modern take on the onion dome constructed of metal.

Pediment

The triangular portion of a building placed above the entablature and usually supported by columns. This building element developed in ancient Greek architecture as the gable ends of temples. The area within the pediment, the tympanum, is often decorated with sculpture, though it can remain unadorned. The example illustrated here forms part of an Ionic portico adorned with egg-and-dart molding and supported by fluted columns topped by capitals with volutes.

Quoin

Dressed stones used at the angles of buildings. Quoins can be decorative or structural, depending on their size, jointing, and the masonry of the building. When structural, they provide additional strength to walls constructed of other materials. Decorative quoins often protrude from the face of the wall and can even be made of brick or other materials. Like decorative keystones, such quoins are utilized to convey ideas of quality, permanence, and wealth.

Raking Cornice

The upper frame of a pediment, below the roof line. A cornice is a horizontal decorative molding that crowns a building, though it can also be found atop doors, windows, and even furniture. At the top of buildings, it also serves the practical function of deflecting rainwater from exterior walls. The classical entablature is similarly crowned by a cornice. A rake is the architectural term for an eave that follows the sloping gable line of the roof. Raking cornices can feature classical ornament, such as dentils or egg-and-dart molding, or may draw from other styles as seen in elaborately carved bargeboards.

Spandrel

The roughly triangular space between the top of an arch and the rectangular frame that surrounds a door or window opening. The term spandrel in architecture can also refer to other interstitial spaces, such as panels above and below windows in the curtain-wall of tall buildings. Spandrels are frequently richly decorated, especially in Gothic and Gothic Revival buildings, though they can also be left unadorned.

Tracery

The stonework elements that support window glass. Tracery developed in medieval architecture as exterior walls thinned and windows became larger. Early Gothic examples, known as plate tracery, featured small geometric openings made from large stone slabs. This later gave way to bar-tracery composed of thinner stone mullions. In addition to allowing larger windows and more intricate designs, tracery protected glazing against strong winds. The term tracery likely derives from the method of design and construction used by masons, who made drawings or tracings of windows on floors and plaster walls. Some churches still show faint remnants of this process.

Uncoursed Brick

Brick laid without regular courses or planned patterns. In masonry, a course is a layer of the same unit running horizontally in a wall and can be arranged in various orientations and patterns. In brickwork, courses employ different bond patterns for structural reasons or decorative effect. These are often associated with specific types of architecture and parts of a building. For example, soldier courses, with bricks laid vertically with their narrowest ends facing outward, are often used for window sills and the tops of walls. Uncoursed brick is a common feature in Tudor Revival style houses, with random patterns found between half-timbering and in the gable ends of the building.

Vestibule

A small foyer or entryway leading into a larger space. Vestibules add security and privacy from the outside and discourage unwanted entrance into homes. They also serve as a waiting space, reduce thermal loss, and provide space for outdoor clothing and shoes. While vestibules can be purely utilitarian and often do not protrude from a building’s facade, they can also be elaborate spaces, decorated with leaded glass windows, plaster molding, and ornate tile floors.

Window

An opening in a wall or roof that is fitted with glass or other transparent material that allows light and air into the building. Windows are one of the most important elements of a building, reflecting its style, period, and regional construction methods. Hinged casement windows, for example, were common in early American houses, while double-hung or sash windows became popular in the early 18th century. In historic structures, builders custom made windows to complement the design in a way that new windows rarely can replicate. Constructed of old growth wood, handmade glass, and assembled with cords, pulleys, locks, and hinges, historic preservationists will always recommend repair and restoration of original windows over replacement. Well maintained original windows can last for many decades longer than modern, mass-produced alternatives.

X-Bracing

A structural element consisting of two diagonal members that intersect. X-bracing, or cross bracing, is used to reinforce and strengthen a structure in both compression and tension. It is often used in bridges or structural foundations as well as High-Tech architecture of the 1970s and 80s.

Yankee Gutter

A drainage system built inconspicuously into the roof so it is not visible along the roofline of the house. Dating to the 18th century, Yankee gutters can be simple or ornate to match the architectural style of the house. They have the advantage of being able to handle larger volumes of water because they are wider and more structurally secure than modern aluminum gutter systems. Yankee gutters also allow intricate details along the roof and cornice lines to remain unobscured. For this reason, they should be maintained and not replaced with modern alternatives that can detract from the aesthetic of historic homes.

Zigzag Motif

A highly decorative, geometric ornamental pattern. The zigzag motif can be made of a variety of materials, such as stone, terra cotta, wood, or metal. It has been a popular architectural embellishment throughout history and used for the adornment of arches in medieval Byzantine, Islamic, Norman, and Romanesque buildings. More recently, it gained popularity in the 1920s in Art Deco buildings and skyscrapers. One sub-style of Art Deco is even referred to as Zigzag Moderne. It is characterized by angular geometric patterns, ornately decorated cornices, ornamental door and window surrounds, and generous use of exotic wood veneers, marble, glazed terracotta, and metals. Zigzag Moderne eventually gave way to Streamline Moderne, with smooth wall surfaces and aerodynamic curves inspired by transatlantic ocean liners.

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