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You can add subtle beauty to a door, window, or room easily with decorative wood trim. Moldings (also called moldings and trims) are pieces of materials with an ornamental or decorative cross-sectional profile. Profiles are made up of convex and concave surfaces, with mixed planes and angles. These various surfaces produce different appearances in the way that light reflects off them. They can be stained or painted to complement or contrast adjacent surfaces. Moldings are formed from wood, composite wood, plaster, plastic, rigid foam, medium density fibreboard (MDF), and even masonry materials.
The most affordable and least expensive moldings are formed from wood and wood fibers. The wood can come from softwood (coniferous) trees, such as spruce, fir, and pine, or from hardwood (deciduous) trees such as poplars, maples, and cherry trees. The most expensive moldings are made of hardwood and are generally reserved for furniture and cabinets. Moldings made from medium density fibreboard (MDF) are less expensive. MDF is made from wood fibers combined with resins and is placed under pressure to form a material that can be easily molded with common tools. It is important that MDF trim is not used where moisture problems can arise, such as in a bathroom or near a basement floor. “Finger joined” moldings are a slightly more expensive alternative to MDF. The “finger joined” moldings are made from short pieces of wood that have been machined at the ends in a pattern that resembles interlocking fingers, glued together at the ends, and then run through a molding machine to create the finished profile. The finger joints can be seen if they are stained, so painting is clearly the best finishing option. The moldings serve many purposes. They are primarily used to make an attractive seamless transition where different surface materials or angles meet. Moldings are considered highly decorative and their use can add unique aspects to rooms, doors, windows, and mantels. They can also be used to cover or hide problem areas and to protect softer surfaces.
Moldings are available in thousands of profiles, however they can be classified into just a few groups, depending on where they are used in a room: floors, doors, walls, windows, and ceilings. Base moldings are generally found at the “base” of a wall where it meets the floor. The base caps are placed on a square table and give the combination a more elegant look. Shoe molds are used where the base plate and the floor meet, which helps protect the base plate and covers up any unsightly gaps between the floor and the base plate. Chair rails are typically placed on the wall, approximately level with the top of the back of a chair. Although chair rails are commonly used for decoration, their name comes from the fact that they protect the walls from being damaged when the chairs are slid back. Chair rails can also be used to finish the top of wainscoting, a type of paneling that covers the bottom three or four feet of a wall. Windows and doors can really stand out when they are “framed” with case trim. The window stool can be added to the bottom of a window, and the aprons under the stool really complete the effect. Picture molding is typically applied a few inches below the top of a wall, and its name comes from the fact that people used to hang pictures from it with wire and picture hooks. This was the best way to display pictures in old houses with plaster walls, where it was not practical to use nails. Crown molding is usually placed at the top of a wall, where the wall and ceiling meet. The moldings that you will most often find here are crown molding. Crown molding is always “suspended”, which means that the back edges are beveled so that they can be positioned where non-parallel surfaces meet. They are used to cover large angles.
There are literally hundreds of different crown patterns and the combinations are practically limitless. Base boards and aprons can be worn behind the top and bottom of a molded crown to make it look more solid and extend your coverage. Crowns can be “built” from multiple patterns, and other types of trim can be added for different effects.
Moldings can be used on the exterior of houses and structures, as well as on the interior. Rake moldings are used where ceilings have a slope or “rake”. Tile trim is placed under the edges of shingle roofs, creating a more visually pleasing appearance than flat boards and helping to support shingles that extend beyond the roof deck. Bed moldings are narrow, spring or flat moldings for the same purpose as crowns. Brick moldings are used as exterior cladding for windows and doors. It is a thick block molding that provides a surface for brick or other exterior cladding, such as siding, to bond together. Drip caps have an angled profile that allows the trim to sit on top of a window or door frame and carry water outside. It usually has a small cove at the bottom to prevent water from running into the structure. Today, most people prefer a non-rotting material for exterior trim. PVC (polyvinyl chloride), fiber cement or composite wood made from recycled plastic and wood fibers are the most preferred materials, due to their low maintenance and reasonable cost.
Whatever your structural project, trim can be used to enhance the appearance of windows, doors, and walls. They can be used to cover any space where building materials and wood products do not fully bond together, and provide a uniform appearance where unsightly cracks may have been present. Visually pleasing transitions can be formed where different angles meet and with a little thought and effort and a few inexpensive tools, trim can add a truly beautiful look to any new construction or home improvement project.