Installing decorative trim molding is one of the quickest and easiest ways to improve the appearance of a room. This can be a simple one-piece, shaped board or it can be an elaborate design made by combining multiple trim profiles and finished lumber.
This page contains information on the types of molding you will find at home stores and lumberyards as well as several examples of common profiles you can use alone or in combination for building baseboards, door and window casings, chair rails and crown.
The examples pictured on this page include a couple of different grades, these are usually referred to as stain-grade and paint-grade. The grade to choose will depend on where it will be installed, whether you want paint or natural wood, and how much money you want to spend.
Stain-grade or solid wood moldings are much more expensive than paint-grade and are often reserved for crown, mantels and staircases where a natural wood finish can add dimension and interest to a room. Moldings that dominate a room like door casings, window casings, chair rails and baseboards are usually done with paint-grade so they can be finished with a color that will accent the walls. This keeps things looking brighter than with natural wood that can be dark and absorb much of the light in a room.
Wood is considered stain-grade or suitable for a clear finish if it is solid and of top quality with no seams, knots or other blemishes. Because the wood will show through the finish, any imperfections like this would be very noticeable. Hardwoods are most often used to make stain-grade trim, with oak being the most popular and available at home stores. These may be finished with a pigmented stain followed by a clear varnish, or a clear coat can be used alone to bring out the natural beauty of the wood.
Because of the irregular grain in hardwood like oak, stain is often used to change the appearance of the wood before varnish is applied. An exception to this is red oak, because of its rich natural color it is often left natural and finished with varnish alone, producing a reddish-brown color that goes well with most room décor. Red oak also takes a stain well, but because it has an open grain the finish will have light and dark areas that can be distracting to some. In these cases a hardwood with a closed grain like walnut or maple is a better choice.
Not all hardwoods are used for stain-grade molding, poplar is one commonly used for custom milled paint-grade molding because it holds an edge well and has a very smooth, hard finish when painted. The grain color of poplar can vary greatly, even in the same piece, making it unsuitable for a stain or clear coat unless the pieces are chosen carefully to get a uniform finish.
With the exception of poplar, hardwoods are typically harder than softwoods and will require carbide saw blades for cutting and shaping. Drilling pilot holes is required when fastening with nails unless a nail gun is used, which will drive and countersink the nails perfectly and is a must if you want the best possible finish.
Paint-grade molding is much cheaper than stain-grade and may be made of wood or one of several synthetic materials. Wood can be solid pieces or it may be manufactured by gluing short pieces together with finger-joints. This manufactured trim is usually pre-primed to make finishing easier, but solid boards will usually be bare leaving the option to paint or stain the finish.
Softwoods including fir, hemlock and pine are most often used to make paint-grade molding, with pine easily the most common because it grows quickly on tree farms and is a very renewable source of raw material. Softwood is very easy to cut by hand with steel saw blades and can be fastened with hammer and nails. It sands easily and planes very smooth which produces a uniform finish when primed and painted. While softwoods are indeed soft and easily dented, the lower price for a paint-grade can easily make up for this flaw.
In addition to softwoods, synthetic materials are used to make paint-grade molding by pressing a profile into plaster, medium density fiberboard (MDF) or plastics like polystyrene and polyurethane. Of these, MDF is probably the most widely available. Plastics are often used to make easy to install ornate crown and cornice pieces, but door and window casing are also commonly found in home stores. Plaster is used mostly for medallions to go around ceiling light fixtures, but plastic medallions can also be commonly found.
This diagram identifies the most common moldings you will find in the average home. Some or all of these may be used in the same room, but in smaller spaces they should be kept to a minimum or the décor can become too busy.
In larger rooms with high ceilings where the wall space can accommodate more decoration, wall frames, picture rails and crown moldings can be essential to warming the décor. Around large doors, a plinth block can help to transition between wider door casings and baseboards.
In addition to the simple profiles pictured on this page, an original and elaborate design can be created using two or more pieces in combination. This may be necessary to match an existing profile or you may wish to have a unique trim design for your room.
Building combination molding like the baseboard pictured here doesn't have to be hard or complicated. Each piece is cut and installed, one on top of the other, to build up this profile.
This baseboard features 3 small pieces stacked on top of a 1x6 and a piece of shoe mould along the floor. Small 1by strips behind the finish board push the face of the trim out making it suitable for mating with thick door casings like those found in Victorian style trim. This is just one design possibility, many others can be built using a little imagination and the stock moldings pictured in the alphabetical listing below.