Basic trim is a tool of the builder, covering up the gaps where different building materials meet. Drywall (also called sheet rock) covers the wall's framing plus insulation on exterior walls. The trim used to cover gaps where the sheet rock meets windows and doors is called casing, i.e. the window casing. Where this same drywall meets the flooring whether it's wood, carpeting or tile, there is also a gap which needs to be covered and that trim at the floor is called baseboard.
Trim can be simple or elegant depending on the style of the home and budget of the buyer. Homes built today typically use the same trim style throughout the house, providing continuity as you go from room to room. Simple trim will be a single piece of wood while more complicated designs can be built up from several pieces of wood combined to form the design.
Baseboard Trim at the Floor
Baseboards are one of the defining features of a house providing what Tom Silva of This Old House calls the “visual anchor.” In old houses, the front room where guests were entertained had the most elegant baseboards.
Today it is common to use the same baseboard throughout the house. To make houses more affordable, cost pressures have driven the design of simple, one-piece baseboard trim. It is not difficult to replace your existing baseboard with more stylish baseboard trim. If you do replace the existing baseboard, it should be at least as tall as the old to avoid having to paint your walls.
One easy approach to building up the existing trim is to add what's called “quarter round” to the bottom of your baseboard. Quarter-round trim is actually one-quarter of a circle with one side that sits on the floor while the other side pushes up against the vertical baseboard (shown above). Quarter-round is used quite often to solve problems, like hiding tile grout that cracks or sheet flooring that curls at the edges.
More elegant baseboards are made up of 3 individual pieces at least 6 inches high and 1/2 to 3/4 inches thick. These pieces include a flat plank, a decorative cap molding on top of the plank and a rounded shoe molding at the base to cover gaps along the floor. With higher ceilings the flat plank can be taller and sometimes this trim can stretch to meet the window trim above as shown on the right.
Casings That Surround Your Doors and Windows
The trim surrounding interior doors and windows is called casing. It's first role is to hide the gaps between the drywall (may be called sheet rock depending on where you live) and the door jambs which are the sides you might brush up against when walking through a doorway. The terminology is the same for windows.
Casing can be tapered (outside edge heavier than the inside edge that touches the door or window jamb or the casing can be square (same thickness on both sides). Square casings can be combined with decorative corner blocks (top corners) and/or plinth blocks (bottom corners) to add visual weight to the opening.
The door casing on the left door below is fairly simple, with the rich decorative touch coming from the wallpaper. The center door has a more complex design with multiple pieces of molding added to create a more majestic, arched doorway (below, center).
You won't always find casing around all sides of windows (4 sides) and doors (3 sides). Especially with plaster walls which are harder, the outside edges will be rounded and the trim will be omitted to give a clean, sleek look as shown on the windows below right.
There are many design options for adding trim to your walls. Many designs are purely decorative while several offer some degree of function too. It is wise to design the entire wall, if not the entire room, before installing the selected treatment so that everything is well coordinated when done.
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