How to Install Crown Moulding

Before you start, measure the length of the walls where you plan to install crown moulding. This will help you determine the amount of moulding you need to purchase for your project. You should always buy 15-20 percent more moulding than you think you’ll need, to cover any cutting or measuring mistakes that may occur. Measure each wall individually from corner to corner, as they may vary in length. Draw a faint line where the bottom of the crown moulding will lay. This will help keep the moulding straight because no room is perfectly square.

Securing the crown moulding to studs ensures a great, snug fit. Use a stud finder to easily help locate the studs you’ll attach the moulding to, and mark the studs with a pencil to ensure you know where they are at all times.

Select a crown moulding style that suits your home's aesthetics. You can choose from various profiles and sizes, or even buy some samples in a few different styles to visualize them in your space before making your decision. Consider the architectural style of your home and your personal preferences when deciding.

Hold the molding against a framing square and measure the gap between the molding's edge and the corner, then cut a piece of scrap lumber to match the measured gap.

Draw guidelines on both the wall and ceiling where you plan to install the molding. When you're ready to install the molding, make sure it lines up with the guidelines you drew.

Start placing the molding on the wall that's opposite the door. Identify the positions of the wall studs by aligning the molding with the wall. Then, mark these stud locations on the molding.

Understanding how to handle crown moulding corners is a crucial aspect of your installation project. Cutting crown moulding corners comes down to two main cuts: inside corners and outside corners.

Inside corners are formed where two walls meet at an angle, typically 90 degrees. For inside corners, a common approach is to cut both pieces of moulding at a 45-degree angle so that they fit together seamlessly.

On the other hand, outside corners are where the moulding "returns" to the wall, extending around the corner. The angle for outside corners may vary based on the specific angles of your walls.

Scarf joints can also be used to create a seamless, overlapping connection. They allow for longer crown molding installations without visible gaps, enhancing the aesthetic appeal of the molding.

Crown moulding corners can also be purchased separately if you’d like to avoid cutting them yourself.

Use a mitre saw to cut the crown moulding at the marked angles. Make sure your saw is set to the correct angle for each type of corner. A 45-degree angle is the most common for inside corners, but outside corner angles may vary depending on your walls. Be sure to follow your measurements carefully.

Using a coping saw to trim any excess moulding can help create a seamless joint. Take your time and carefully follow the profile of the moulding for a precise fit. After cutting, you may need to use sandpaper to smooth any rough edges. Check the joint by fitting it against a piece of scrap moulding to ensure everything is good.

Begin installing the crown moulding along the walls, starting at one corner and working your way around the room. It is usually advised to start on an inside corner, making sure that your crown moulding pieces fit together seamlessly as you go. Secure the moulding with a brad nailer into the studs you marked earlier for extra stability. Continue around the room until you’ve got all of your moulding secured.

To achieve a seamless finish, you’ll need to fill any small gaps or imperfections that may be showing. Use paintable caulk to fill these gaps, applying a thin, even bead along the joints where the moulding meets the wall and where two moulding pieces join. Make sure to smooth the caulk with a damp finger or a caulk finishing tool for a clean look.

If your crown moulding was purchased primed or unfinished, this is the perfect time to paint it. Choose a paint color that complements your room's decor and apply a couple of coats evenly to the moulding. Painting your moulding not only makes it look great, but also adds a protective layer.