Brick molding is a strip of material used to close the small gap between a brick wall and the frame of a door or window recessed into the wall. There are no bricks, or masonry, in the molding.
Brick frame around the door.
Hardwood was the traditional material used for molding bricks. As hardwoods are resistant to decay and moisture, this type of molding had a long lifespan, sometimes up to 50 years. Today, it is usually made of softwood, usually spruce or pine. Softwood is much more likely to be damaged by weather or rot than hardwood and therefore has a much shorter lifespan.
Softwood brick molding lasts longer if all surfaces are primed and painted before installation, including the cut edges. The use of metal flashings, so that the frame does not touch the brick, also increases the lifespan. The molding must always be caulked and painted. If installed correctly, it can usually be repaired for 15 years.
Today, other materials can be used for brick molding. Many forms of plastic cost a little more than softwood, but they have an expected lifespan of around 50 years and don’t need to be repainted regularly. They are made of PVC, the type of plastic used in plumbing fixtures. There are three main types of plastic: hollow PVC, laminated wood and solid PVC.
The hollow PVC brick molding is in the shape of ordinary wood molding, but it is hollow inside. It’s light and easy to work with. However, it breaks easily when nailed in place and creases easily during use.
Plasticized wood has a core made of wood dust mixed with plastic glue. A thin PVC “film” covers all sides. This type of brick mold can be sawn, nailed and painted like wood, but it doesn’t require painting, it doesn’t absorb water, so it doesn’t rot. It can crack, especially when the nails are hammered in. It is best to drill holes for nailing in this type of molding.
Solid PVC brick molding is easy to work with and will not shatter when nailed. It is not damaged by wood or insects and is resistant to sunlight damage. It can be painted, but no painting is required for a long service life.
No matter what kind of brick mold is used, it must be installed correctly and caulked thoroughly. A good seal is essential. Even if the molding itself doesn’t rot, any water that seeps behind it into the wall will cause damage over time.