Why you should never install MDF in your bathroom and what to use instead

Medium Density Fiberboard, better known as MDF, is an appealing trim choice for homeowners, particularly due to its low cost. But installing this in your bathroom can mean disaster down the road.

Essentially, MDF is an engineered wood product made in much the same way as cardboard. Wood fibers are combined with wax and a resin binder, and formed into panels by applying high temperature and pressure. What that means is that when it gets wet, those fibers expand and pull away from each other, losing strength and durability.

The example below shows MDF baseboard trim in a bathroom that is less than 7 years old. And while you may think that 7 years is a decent lifespan, you can tell from the photo that this trim started deteriorating long before the photo was taken.

So what are better alternatives?

Natural wood such as pine, poplar, maple, etc., while more expensive up front, are inherently more resistant to water and will last much longer, giving you more value for your money. There is also more flexibility in the design, as the natural wood can either be stained and varnished for a natural look or can be painted. An added bonus is that paint sticks to it much better as well.

If you like the look of painted trim, another alternative is to use PVC trim, which is a plastic trim that can be painted however you wish.

If you must use MDF, make sure to paint ALL sides with high quality paint to seal it as best you can.

Curious what kind of trim we would recommend in your bathroom?