The term “architectural millwork” encompasses a range of materials and products. Also known as “architectural ornamentation,” “detailing,” “carpenter art,” or simply “trim,” this refers to the mouldings, posts, columns, and other detailing applied to house exteriors.

Architectural detailing includes shutters that flank windows, pediments and pilasters that surround doors, dentil and crown mouldings, columns, and other elements that add interest and anchor a house’s architecture in the vernacular of a given period and style.

Much millwork serves a functional role, too. Mouldings hide the transitions between differing materials, and columns provide support, for example.

If you intend to build a traditional-style home, or you own an older traditional house, it pays to be familiar with decorative millwork.

The trim of many older homes often has been removed or, where it has not been removed, it’s in shoddy condition, because millwork is particularly vulnerable to the abuses of harsh weather.

The traditional material for architectural detailing is wood—typically pine, fir, redwood, or cedar. Ornate patterns of moulding and millwork are made up by combining a variety of simpler wood moulding profiles.

New architectural detailing is often formed from high-density polyurethane. Though it isn’t an ”authentic” material, polyurethane foam is equally workable and not subject to many of wood’s drawbacks.

Polyurethane mouldings don’t expand and contract, warp, decay, or require heavy maintenance. And because intricate polyurethane mouldings are made as single-piece units, they’re also much cheaper to install.

Some vinyl siding manufacturers also offer a range of decorative classic millwork that coordinates with their systems. These include door and window surrounds, shutters, corner posts, dentil mouldings, and more.

Columns may be structural or merely decorative. Structural columns are made from wood, extruded aluminum, or fiberglass composites. Non-structural, decorative columns, made from polymers, are hollow in the center to allow for a wood or metal post.