Drip caps are projections placed on the exterior of buildings to help redirect rainwater. Often, the drip cap is found over windows and doors, serving as a means of diverting the flow of rain so that it drips away from the framing. The cap sometimes takes the form of decorative molding, while at other times is created using sheet metal to protect the door or window casing.
A door or window drip cap can be composed of several different materials. Molding designed to divert water away from the framing may be created using brick or some other form of masonry. A wooden piece of trim can form a very simple and almost imperceptible cap that allows the water to drip away from the frame. When drip cap flashing is used around window and door frames, sheet metal is the most common choice.
The drip cap is also part of many roof designs. As with caps placed above windows and doors, the roof drip cap diverts water away from areas of the roof where water would otherwise collect and possibly cause damage. In this application, the cap diverts the water so it can drain off the roof and into drainpipes, where it is routed away from both the roof and the exterior walls of the building.
With homes that are outfitted with vinyl or aluminum siding, these materials are often used to create the drip cap. This allows the cap to fit in nicely with the rest of the structure, instead of appearing to be a feature that was added later. Both the aluminum drip cap and the vinyl drip cap are usually simple designs that are either the color of the siding itself, or matches the color of the framing around the doors or windows.
The replacement or installation of one of these caps is a relatively easy process. Many caps are designed to adhere to both the exterior wall and the upper portion of the door or window frame. Depending on the materials used, wood glues, screws, and other common building supplies are used to manage the installation process. Mass produced drip caps usually come with step by step instructions to aid in the installation process, making it a relatively easy task for any homeowner to replace or install drip caps when necessary.
Because a drip cap can be strictly functional or also be decorative, homeowners should look at several different designs before making a purchase. Decorative caps can add to the visual appeal of the home, if the caps are similar in style to the general architecture of the home. However, a decorative cap can sometimes negatively impact the look of the exterior. When this is the case, going with a cap that is simple and relatively unobtrusive would be a better option.