How to Install Baseboard Molding and Interior Trim

Want to add instant character to a room? Consider upgrading molding and trim. While the installation itself isn’t complex, cutting and measuring the angles can be tricky. However, this is one upgrade that can work wonders for the value of your home without significant investment!

Removing old trim

Score a line with a utility knife along baseboards and any molding to help it release more easily from drywall. Using a hammer, tap the end of a pry-bar or putty knife into the gap and then use the pry-bar to work it free, working your way around the room. Remove any leftover nails.

Choosing trim

Select molding or trim that complements the space and each other. Several species of wood, such as pine and poplar, are often used for stain or paint grade moldings and trim since it is generally less expensive and easy to work with. One commonly used baseboard is the three-inch rounded or stepped board. The top of the baseboard gives a softer, more decorative corner, and it is one of the less expensive and popular options. Custom hardwoods can also be specially ordered.

Measuring and installing

Use a measuring tape to calculate the measurements of the space that will need a trim. Write down each measurement and continue around the room until all walls are measured. Base trim is typically sold in linear square feet so divide the total number of inches by 12 to convert from inches to linear feet. Not sure on the conversion? Bring your measurements in; our Cardinal team will help you figure it out.

You will want to paint or stain your trim before you install it. It’s an easy process that can dramatically speed up paint time and create cleaner lines. Use sawhorses over a drop cloth in a garage or sunny outdoor space. A paint gun is ideal for fast and efficient painting, but paintbrushes work as well. Just sand lightly between coats for a smooth finish. We recommend semigloss paint for most moldings.

When you attach the trim to your walls, it’s best to use a nail gun. Select a nailer that’s between 15 gauge and 16 gauge. Trim nails average between 1.5 inches and 2 inches. The best nails for trim are those that can be covered with a bit of wood filler and painted over so that the baseboards yield a smooth, clean look.

Set the baseboard or molding along the wall; You’ll need to create mitered edges at the ends of the baseboard pieces. These edges permit pieces of baseboard to fit together perfectly at an interior or exterior corner. Miters are not easy and require some practice. Use scrap and make a few test cuts to get the hang of it. A mitered corner forms by joining two pieces of wood, each cut to a 45° angle. Another method for corners is coping, which uses a detailed cut following the shape of the curved trim.

Shoot your finish nails accurately into wall studs to firmly secure them. Drywall has poor holding power. A stud detector can help you find wall studs quickly.

Conceal with a paintable or stainable wood filler or a color-matched wood filler putty. If you are painting your trim, you can use a utility caulk to fill any minor gaps to make them disappear.

Have questions? Visit one of our three Cardinal Home Center locations for assistance.

Pro Tip:

If you have thin crown molding or baseboards that you want to “dress up,” nail a strip of base cap molding 4-6 inches below your crown or above your baseboard (depending on the thickness you prefer) and paint the drywall in between with the same trim paint. This works exceptionally well in rooms with a bold color on the wall. It gives the ceiling height and allows the wall color to pop.