A molded door is a popular door style for interior residential openings. Rather than solid wood or metal, these units consist of hardboard or composite materials with a series of panels or designs pressed into the face of the door. The molded door mimics the appearance of a traditional stile and rail door, but comes with a much lower price and quick manufacturing time.
Manufacturers start with a foam or particleboard core, then wrap the core with a layer of exterior skin. Depending on the model, the skin can be made from medium-density fiberboard or hardboard. Some models designed for exterior openings feature a thermoplastic skin that resists moisture and wear, but this type of design is less common.
The skin is bonded to the core using special adhesives to form a single piece of material. Next, the entire unit is placed into a mold to create the desired appearance on the face of the molded door. The mold applies both heat and a high level of pressure to the door so that when the mold is removed, the pattern remains on the door.
Consumers can choose from many different molded door designs, including traditional six-panel styles and more elaborate custom models. Some manufacturers prime and paint the doors before selling, while others sell them unfinished. Before installing these doors, buyers should seal the wood to minimize the risk of moisture and humidity damage.
One of the primary benefits of using a molded door rather than a solid wood model is the significant cost savings associated with these units. The hardboard or fiberboard surface allows the door to readily accept paint, and the manufacturing process for these doors makes design options virtually limitless.
Molded doors don't have the same solid weight and feel as a standard door, which may allow more noise to pass through the building envelope. The skin on these doors tends to hold up poorly against rain or humidity, and may show signs of warping or swelling over time due to natural moisture in the air. Because the surface of the door consists of only a thin skin, it cannot be sanded during refinishing, and most won't accept traditional wood stains.
These doors should not be confused with panel or stile and rail door designs. While molded doors consist of a solid piece of material, panel doors often feature trim elements arranged on the face of the door to form panels or patterns. Stile and rail units use a combination of vertical and horizontal wood elements joined together to form patterns. They tend to come with a high price and take much longer to manufacture than a simple molded door.