How to Install Crown Molding

A simple way to give your room a regal feel

Paul Pogue
Written by Paul Pogue
Updated September 9, 2022
Installing crown molding in home with nail gun
Photo: JodiJacobson / Getty Images


You've got this!

Time to complete

4 hours

Expect to spend an afternoon installing crown molding in the average-sized room. However, if your room has multiple corners and alcoves, or if you need to paint the boards ahead of time, the project can take longer.



If you already own the tools, this DIY is a no-brainer.

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What you'll need:


  • Stud finder
  • Angled paint brush or paint sprayer (optional)
  • Brad nailer
  • Caulk gun
  • Ladder
  • Miter saw
  • Tape measure
  • Safety glasses


  • Pencil
  • Painter’s tape
  • Crown molding
  • Paint or stain (optional)
  • 2 ½” nails
  • Paintable caulk

Elevate your interior’s aesthetic by installing crown molding where the wall and ceiling meet in the room. This type of trim adds elegance and a polished finish and provides a sense of completeness. While cutting the crown molding can require more carpentry skill and attention to detail, installing the cut boards is a straightforward project. Use this guide to learn how to install crown molding and give your room that wow factor.

  1. Take Measurements

    Man taking measurements of ceiling on ladder
    Photo: JodiJacobson / Getty Images
    • Using a tape measure, measure the walls from corner to corner to determine how much molding to buy. Remember to purchase an additional 10% of materials to allow for waste and potential inaccuracies when cutting.

    • When measuring the wall, start from where the bottom edge of the crown molding will sit (for example, start 3 inches below the ceiling for trim that is 3 inches wide).

    • Measure and mark the studs with painter’s tape using a stud finder. 

    • Transfer these measurements to the boards, marking the bottom of the crown molding with a pencil. Be sure to show the angle where the boards meet in the corner for accuracy when cutting.

    Pro tip: It’s helpful to make a sketch of the room to serve as a blueprint to show the measurements of each wall, alcove, and bump out. This will help you better visualize the room when you’re looking for materials at the home improvement store.

  2. Prep the Area

    Bringing crown molding inside before installation
    Photo: photovs / Getty Images
    • Move all the furniture to the center of the room.

    • Remove any old crown molding boards using a pry bar with a scrap piece of wood behind it to protect the wall from damage.

    • Clean your miter saw from any sawdust and debris from previous projects.

    • Bring the boards inside for at least 24 to 48 hours so they can acclimate to their new environment.

    • Dust the ceiling to remove any cobwebs or debris.

  3. Measure and Cut the Boards

    Cutting crown molding board with miter saw
    Photo: ungvar / Adobe Stock

    Using your measurements as a guide, it’s time to cut the crown molding. There are different techniques you can use when cutting the boards, depending on the layout of the room. For a more in depth description of this step you can refer to our How To Cut Crown Molding Guide, but here are some of the basics.

    • Scarf Joint: A scarf joint is used when one piece of crown molding is shorter than the length of the wall to connect to a new piece. The pieces are cut at opposing 45-degree angles so they overlap, creating a seamless transition.

    • Inside Corner Cut: For 90-degree corners and alcoves in the room, make an inside corner cut. For this type of cut, the left side will angle up to the left and the right side angles up to the right, so that the top edge of the board is longer than the bottom edge. Set your miter saw to a 45-degree angle and flip the board upside down. Swivel the saw to match the direction and angle of the mark and cut the board.

    • Outside Corner Cut: If you have any bump outs in the room, you will make an outside corner cut. An outside corner cut is the opposite from an inside corner cut, as the left side will angle to the right and the right side will angle to the left, so the bottom edge is shorter than the top edge. Turn the board upside down and set the miter saw at a 45-degree angle, in line with your pencil mark to make the cut.

    • Coped Joint: When cutting inside joints, curved shapes and intricacies in the molding, as well as imperfections in the ceiling and wall can cause the trim to not align properly. In this instance, you can create a coped joint, so the boards fit flush against one another. Remember, this technique requires more carpentry skill and a specific coping saw.

  4. Paint Or Stain the Boards (Optional)

    Painting crown molding trim with spray gun
    Photo: NoSystem images / Getty Images

    Depending on the boards you buy, they may need to be painted or stained, and it’s best to do this step after cutting but before nailing them into the wall. For example, MDF often comes pre-primed, but you may want to add another coat of paint to fill in any bare spots, to paint a color other than white, or to add a glossy finish to the board. Moreover, if you purchased bare wood boards, you may choose to stain or paint over them before installing. You can either paint them using an angled paint brush or a paint gun, depending on your preference. 

    • Painting the boards with a paint sprayer: For the experienced DIYer, a paint sprayer can be used to complete this step more quickly, making this a good choice when working with a large amount of material. It also works well for boards that have intricate details, as it helps the paint cover even the smallest of crevices that a brush may not reach. In a well ventilated room, wearing the proper protective equipment (such as a respirator), lay the boards out and fill the spray gun’s reservoir. Evenly apply the paint in the same direction, wiping away any drips or splatter from the boards with a spare paint brush. Allow the boards to completely dry, then apply a second coat.

    • Painting the boards with an angled paint brush: An angled paint brush works well for beginners, as getting an even coat with a sprayer can be a challenge. Dip a high-quality brush into the paint can and wipe off the excess paint on the edge. Apply the paint in an even coat along the board, working with the grain of the wood. Allow the paint to fully dry, then apply a second coat.

  5. Attach to the Wall

    Man affixing crown molding to wall using brad nailer
    Photo: Brett Taylor / Getty Images

    Once you have cut each piece and the paint has fully dried, you can attach the crown molding to the wall. Start with the inside corner of the long wall in the room. Using the stud marks on the wall for reference, hold the piece in place with the corner and nail into the wall using your brad nailer and 2 ½ inch finishing nails. Continue in the same direction throughout the room, attaching the pieces to the wall so they fit snugly with the preceding board.

    Pro tip: It is recommended to use a nail gun for this step, but if you don’t have one, you can hammer the boards into the wall (however, you will need to pre-drill the holes to avoid splitting the boards).

  6. Make the Finishing Touches

    Sealing crown molding edge with caulk
    Photo: Vadym Plysiuk / Getty Images
    • Fill in the nail holes with a paintable caulk.

    • Use a caulk gun to seal the top and bottom edge of the molding, fill in any gaps in the corners or scarf joints, and to fill in nail holes. Wipe away excess caulk with a rag or your fingertip for a smooth finish.

    • Inspect the boards and apply touch up paint over nail holes or to fill in any visible bare spots. 

Tips When Buying Crown Molding

  • Inspect the boards and steer clear of trim that has divots, notches, warping, or other imperfections before purchasing.

  • Choose the width of the crown molding based on the height of your ceiling. For ceilings that are 8 feet tall, 3 to 5 inch width crown molding will provide a balanced look. For 9 or 10 foot tall ceilings, opt for a wider trim (around 4 to 8 inches). Ceilings taller than 10 feet look proportionate with an even wider trim. Remember, if you are adding the molding to an entry room or great room, a larger size will make the most visual impact.

  • There are different materials used to construct crown molding, such as wood, PVC, polyurethane, and plaster. Use our Best Crown Molding Materials guide to compare and contrast to find the best option for you.

  • Crown molding comes in various styles and the different profiles can make a difference on the overall look of the room. For example, you can achieve a more modern aesthetic by going with a sleek and straight-lined trim. Conversely, crown molding with intricacies look more ornate or traditional.

  • When deciding on a paint color for the trim, consider the wall’s existing paint color, the features within the room, your style preferences, and the architectural elements of your home. While white is a common choice due to its versatility, you can also match the crown molding to the wall paint color for a monochromatic effect. Moreover, you can shake up the design and paint the trim a contrasting color to add a visual point of interest in the space. Opt for an interior, acrylic-based paint in a semi-gloss or high-gloss finish. This type of paint and finish is easier to wipe down and clean for a low-maintenance option.

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