Should You Use MDF, Wood, or Plastic for Baseboards and Trim?

Using MDF Baseboards and Trim

Medium-density fiberboard, like other aggregate building materials such as quartz counters, is derived from the same source emulating: trees. Yet the similarity ends at the mill. Soon after entering the mill, MDF's wood source (usually small branches) is pulped into a mash, then re-formed into a hard building product. 

Within the home, medium-density fiberboard (MDF) is increasingly used for kitchen and bathroom cabinets, shelves, and furniture.

Lower cost is the driver behind MDF baseboards' popularity. The most popular size of baseboard material is 3 1/4 inches high. Within this category, solid, unprimed wood is the most expensive product, followed by primed pine and MDF.

While there are cost differences, these differences are slight, especially in small applications. Many home centers and lumberyards price MDF up to 10% less than hemlock or poplar and can even be the same price as primed, finger-jointed pine. Such a minor cost difference may not be noticed in a small room or two. But when installing hundreds of linear feet of baseboards, MDF tends to be favored by economy-minded owners, contractors, and builders.

MDF baseboards can be easier to install than real wood baseboards. MDF baseboards' soft material cuts easily and does not split under the force of power-driven brad nails or even manually hammered finish nails. Resulting blemishes during installation can also be easily sanded out of the surface, another characteristic that makes MDF baseboards popular.

Laminate flooring provides a perfect analogy to MDF baseboards. The fiberboard base by itself would likely be the worst possible choice for flooring material, similar to MDF. Yet when paired with a hardy transparent wear layer and tightly seamed on a good subfloor, laminate's fiberboard can provide a suitable flooring surface for many years.

MDF, as molding, works in the same way. Priming and painting provide MDF with a thin protective shell. But it's mainly the wall behind the MDF baseboards that acts as its structural support. MDF baseboards on straight runs are nearly as strong as real wood baseboards. Outside corners, though, are MDF's weak points, since these areas are prone to chipping. MDF baseboards can last 10 years or more if maintained and kept dry.

Using Wood Baseboards and Trim

Real wood baseboards, such as those found in home centers, tend to be made from softwoods such as long, uninterrupted pine boards and finger-jointed pine or hardwoods such as oak and hemlock.

Softwoods typically are primed and painted, though not always. While hardwoods can be primed and painted, it defeats the purpose of purchasing expensive hardwoods to cover up the beauty of the grain with paint. As a result, hardwood baseboards are usually stained and sealed.

With real wood baseboards, you have a natural wood grain. With MDF, there is no wood grain and the baseboards must be primed and painted. MDF baseboards are usually sold primed because the material ships better this way with less risk of damage.

Real wood, even softwood, is stronger than MDF. So, if you anticipate installing baseboards in a high-traffic, high-impact environment, you would want to purchase real wood or even PVC baseboards. Because primed and painted natural wood is only marginally better than MDF at standing up against moisture, PVC is your best bet for highly wet spaces.

Actual wood baseboards can split when nailed; MDF and plastic never have this problem. So care must be taken when installing these baseboards, and some excess should be figured into the purchase price.

Also, be sure to check for straight baseboards. Because MDF is an engineered wood, all pieces should be perfectly straight. Natural wood may be bowed. It is better to reject inferior pieces at the store than on the job site. Quality wood baseboards can last decades when properly maintained.

Using Plastic Baseboards and Trim

Plastic is the universal term for baseboards and trim made of polyurethane, polystyrene, or polyvinyl chloride (PVC). Plastic baseboards and trim have slowly gained acceptance, but MDF and natural wood still tend to be more popular materials.

Plastic baseboards and trim are 100% waterproof, making this an ideal material for bathrooms, laundry rooms, and other high-moisture environments.

While termites, carpenter ants, and other wood-boring insects are less of a concern indoors than outdoors, it's still helpful to use a material insects don't like. Since plastic baseboards and trim have no organic content, they do not supply food for insects.

One disadvantage of plastic baseboards and trim is its high cost. Installed in a small room, like a bathroom, this may not be an issue for many homeowners. The costs add up quickly for larger projects.

Plastic baseboards, especially PVC, can last decades when properly installed out of direct sunlight (or they could warp) and kept well-maintained.

How to Decide on Baseboard and Trim Material

If you want the look of natural wood, the decision is clear: solid wood baseboards. Hemlock, oak, pine, poplar, and maple are popular solid wood baseboards for staining.

If you are installing baseboards in great numbers and want an easy installation, choose MDF baseboards since they cut and nail up with little problem.

If you are installing in a wet application, then choose primed wood or, even better, plastic baseboards, as MDF should not be used in moist areas, such as bathrooms.