By Michael Good | House Calls

If it seems your contractor is speaking another language, that’s because, well, they are.

Many of the words used by builders today are hundreds, or even thousands, of years old. Some have their origins in the days of the guilds that jealously guarded the secret practices, formulas and methods involved in making plaster or paint or joinery or finishes. Others are as old as the Parthenon — which may explain why it all sounds like Greek to you.

But that doesn’t mean you can’t learn the lingo; the terms are now available for all to know. And if you hope to restore your Craftsman, you are going to have to talk like a craftsman.

To that end, here’s a short guide to Contractor Speak. For a more complete introduction, pick up a copy of Francis D.K. Ching’s “A Visual Dictionary of Architecture,” an illustrated guide to all things architectural, including arcane names for archaic house parts.

Apron: Not to be confused with the shop apron (an item of clothing) or the theater apron (the portion of the stage that extends beyond the curtain line), this horizontal flat piece of trim molding sits directly beneath the stool. The apron, side casings and cabinet head all form the bottom part of the wood trim that visually frames the window.

Casement: A window sash that opens on hinges mounted on its left or right side, which can swing in or out.

Coped joint: A way of joining two pieces of wood that adapts one molding shape to the other. It masks any movement that occurs as the molding — and house — expands and contracts. Requires a modicum of skill and patience, as well as a hand tool with a thin blade called a “coping saw.”

Classical Orders: The Greeks were obsessed with the concept of “order.” In architecture, order, according to Ching, is “a condition of logical, harmonious or comprehensive arrangement.”

In the early days of the republic, American architects and builders followed the classical order. That’s why the houses we now call “Colonial” resemble Greek temples on the outside.  On the inside, classical stone elements from Greek and Roman facades were adapted in wood for the door and window molding.

Craftsman- and Prairie- style designers adapted the classical order to their needs.  Today, we still use many of the classical terms, such as column, capital and cornice. And while most contractors can’t tell their fascia from their scotia, a knowledgeable preservation carpenter knows how to restore a “sense of order” to a house that has lost its original design.

Dentil: A tooth-shaped decorative element, adapted in Queen Anne, in Craftsman and Prairie houses from the Ionic, Corinthian and Composite cornices. The name is derived from the Latin word for tooth.

Dovetail: A lap dovetail or half-blind dovetail joint is composed of interlocking wedge shapes made to be invisible on one side, such as the front of a drawer. It is a superior and time-consuming way of joining two pieces of wood, and its presence usually means the carpenter was highly skilled, and that the owner, builder or architect cared about the details.

Double hung: A window composed of two vertically sliding sashes in adjacent tracks, separated by a thin parting bead and hung from ropes suspended by pulleys, and usually balanced by counterweights that are hidden in channels inside the wall. It was the most common type of window in the first two decades of the 20th century.

Heart: The older center of the tree — no longer alive — that produces the densest, knot-free, and most desirable lumber for clear-finished interior molding and built-ins. In old houses, heartwood comes from “Old Growth” trees, meaning forests that predate modern logging.

Hollow clay tile: A little-known but frequently used building material resembling a concrete block, but made from high-fired clay that is structurally strong and durable. When covered with plaster, hollow clay tile was widely used for bungalow porches, and sometimes present in the stucco-covered Prairie- and Spanish-style houses by builders such as Nathan Rigdon and Ralph Hurlburt.

Miter: A joint formed by two pieces of molding each cut at an angle, usually 45 degrees. Mitered joints for window casings are more common for Spanish- and Tudor-style interiors.

Molding profile: Think of the profile of a face. Despite efforts by millwork shops in the late 19th century to standardize them, there are hundreds of molding shapes. These profiles are composed of eight principal shapes: scotia, cavetto, ogee, reverse ogee, astragal, torus, ovolo and fillet.

Greek moldings are based on the ellipse; Roman moldings on the circle. Although many molding profiles from the last century are no longer mass-produced, most can be recreated by Frost Hardwood, which back in the day milled some of the trim used in San Diego bungalows.

Mullion: A vertical stick of wood between panes of glass.

Muntin: A milled piece of wood with a groove — or “rabbet”— that holds a pane of glass in a window. A mullion is a muntin, but not all muntins are mullions.

Original: Any part of an old house that was present when construction was finished and the Notice of Completion was filed. This can also refer to anything that the contractor wants you to save.

Rail: A horizontal element — often made of wood— such as a picture rail, plate rail or handrail. In windows and doors, the rail’s companion member is the stile, which is vertical.

Rustication: In early-20th-century houses, this is any process that results in something new looking old, such as a beam in a 1920s Spanish-style house that has been hacked with various tools to appear roughly made and centuries old.

Sash: The frame, usually wood in old houses, that holds the glass windowpane. It can be movable or fixed.

Skirt: Another name for the apron. But if you want to appear cool, call it the apron. And you’ll only wear your apron when you’re alone in the shop — not on the job site.

— Contact Michael Good at [email protected].