How to Build Up Baseboard Molding

Bulking or building up your baseboard molding can be done in a few steps. The size and style of your existing baseboard and trim will determine the complexity of the job. If your existing baseboard is relatively plain with a flat edge then simply adding a capped trim can increase its size. Painting the baseboard trim a glossy white will also help it look bigger against the flat wall.

Simply adding a capped baseboard trim will increase its bulk and visibility.
  1. Sand down the bumps, scratches and top edge of the existing baseboard if there is no existing capped molding. Attach the unpainted baseboard pieces above the existing pieces with nails or a nail gun compressor. Make sure the thickness of the new pieces matches that of the existing pieces. If a slight edge exists then it will be necessary to sand the raised areas down to match. If there is a capped trim on the top edge of your baseboard than it will be necessary to pry this off with your pry bar before sanding and attaching the new pieces.

  2. Remove the existing baseboard if it has a permanent routed trim on the top edge. Place the new flat-edged pieces at the bottom first, then attach the old baseboard with the routed top edge above the new pieces. Sand out any edges, scratches or bumps before preparing to paint.

  3. Fill in any cracks or separations with wood putty. Let the wood putty dry before sanding it smooth. After the baseboard has been sanded you can prepare it to be painted. Remember to clean the area and lay down your plastic to protect the floors. You may also want to tape the wall along the top edge of the baseboard to prevent any mess.

  4. Add a capped trim to the baseboard molding to increase its size and visual presence. Replacing existing baseboard trim with a larger or bulkier style can quickly build up the look of your existing baseboard. It is necessary to repaint the entire baseboard with a fresh coat of paint to maintain consistency of color.

  5. Replace the entire baseboard if necessary. If the task at hand is too time consuming or the condition of the existing baseboard is questionable then simply replacing the entire baseboard with a new and larger trim will do the trick. This can be a more expensive option and you will still need to paint the new baseboard as well.

About the Author

After completing his college screenwriting studies David Slate began work with an animal welfare organization creating educational materials. Then traveling abroad, he taught English in Prague for two years. In 2005 he moved to New York City and works in media production as a fine artist and designer. Also a playwright, his short works have been in local New York City festivals.