How do you install crown molding corners?

Installing crown molding corners can seem daunting, but with the right tools and techniques, it can be done smoothly and beautifully. In this comprehensive guide, we will walk through the entire process step-by-step.

What is Crown Molding?

Crown molding is decorative trim that is installed where the wall meets the ceiling. It is designed to cover the seam and transition between wall and ceiling. Crown molding adds an elegant finish to a room, providing visual interest and architectural detail.

Crown molding comes in different styles and materials. Common types of crown molding include:

• Polyurethane – lightweight and low cost but less detailed
• Wood – natural material that can be carved and painted for ornamental looks
• Plaster – ornate styles well suited for traditional décor
• Polystyrene – inexpensive but mimics look of real wood and plaster

The profile refers to the cross-sectional shape of the molding. Some common profiles are ogee, cove, and egg and dart. The profile will determine how much shadow line and architectural detail the crown molding provides.

Tools and Materials Needed

Installing crown molding requires some specialty tools and materials. Here is what you’ll need:

• Miter saw – for precisely cutting angles
• Table saw – alternative to miter saw for cutting long pieces
• Miter box with hand saw – for minor touch up cuts
• Coping saw – for cutting profile contours
• Nail gun – preferably 18 gauge finish nailer
• Hammer
• Wood glue
• Painter’s tape
• Stud finder
• Laser level or chalk line – for marking guideline
• Ladder
• Filler – joint compound or wood filler
• Sandpaper
• Primer and paint
• Caulk
• Crown molding
• Trim nails

Make sure you have all these items on hand before starting the installation project.

Step 1: Measure and Cut Crown Molding

The first step is to precisely measure each wall and then cut the crown molding to fit those measurements. Crown molding is sold in 8, 10, and 12 foot lengths usually. You will need to cut the pieces to size:

1. Measure the length of each wall and mark the crown molding to the correct length. Add 1-2 inches to allow for trimming.
2. Cut the mark using a miter saw set at a 45 degree angle. Cut slowly and smoothly.
3. Test fit each piece and trim if needed for an exact fit.

Use a miter box and hand saw for minor trim cuts. For longer pieces, use a table saw. Cut several test pieces on scrap wood first to calibrate saw angles before cutting the final molding.

Tips for Cutting Crown Molding

• Always cut with the decorative side facing up so profile is visible.
• Cut gradually and softly to avoid rough edges.
• Use a fine blade designed for trim cuts.
• Cut pieces slightly long then trim for a perfect custom fit.

Step 2: Cut the Corners

Cutting the crown molding corners requires more complex angled cuts. There are two main methods – coping and mitering.

Coping the Corners

Coping involves cutting the profile contour of one piece so it matches the adjoining piece precisely. Follow these steps:

1. Place one corner piece flat on the table saw and run the corner along the fence to cut the profile.
2. Use a coping saw to hand trim and smooth the cut to match the profile exactly.
3. Test fit the two pieces to ensure a tight seamless fit.

Coping creates tight joints but takes more time and skill.

Mitering the Corners

Mitering uses angled cuts to join corners:

1. Cut each corner piece with complementary 45 degree miter cuts.
2. Use a test piece first to adjust the saw for a precise miter.
3. Join the two mitered pieces to form a 90 degree corner.

Mitering is quicker but may leave small gaps that require caulk.

Tips for Cutting Corners

• Always miter the top corner piece and cope the bottom for best results.
• Use a miter trim guide for perfect angles.
• Take time to test piece first before cutting final molding.
• Ensure blade is 90 degrees to the fence when cutting miters.

Step 3: Install Molding

Once all the pieces are cut, it’s time to install the crown molding on the walls:

1. Mark a guideline on the walls 1-2” below ceiling using a laser level or chalk line. This indicates where bottom edge will be.
2. Apply construction adhesive in a zig zag pattern to back of the molding.
3. Use a nail gun and trim nails to fasten the molding to the wall studs, not just drywall. Pre-drill holes to avoid splitting.
4. Nail every 16 inches and within 2 inches of each end.
5. Use scrap blocks to evenly press molding into place as you nail.
6. Do the corners last, applying glue and nailing carefully.
7. Use painter’s tape to hold corners firmly together as adhesive dries.

Take extra care when installing crown molding to ensure it goes up straight and corners fit together cleanly.

Installation Tips

• Always nail into studs for a secure mount.
• Use a level frequently to check for straightness.
• Cut pieces slightly long to allow for adjustment.
• Have someone help hold corners together as they are mounted.
• Fill all nail holes with joint compound once mounted.

Step 4: Finish the Molding

The final step is applying caulk and paint for a polished finish:

1. Use painter’s caulk to fill any small gaps or cracks, especially at seams and corners.
2. Allow caulk to fully cure overnight before sanding smooth.
3. Lightly sand with fine grit sandpaper to prep for paint.
4. Apply primer paint and let dry completely.
5. Finish with two coats of topcoat paint in desired color.
6. Touch up paint thickness around carvings and contours.
7. Remove painter’s tape after paint has cured overnight.

Proper prep and paint application will give installed crown molding a flawless built-in look.

Finishing Tips

• Use a high quality caulk that matches the molding color.
• Carefully fill all nail holes and imperfections.
• Lightly sand between paint coats for maximum adhesion.
• Use a small foam brush for hard to reach spots.
• Choose a satin or semi-gloss sheen for durability and shine.

Conclusion

Installing crown molding corners yourself can add great architectural detail and visual appeal to your space. While the process requires careful measuring, cutting, and installation, the results are well worth the effort. Going step-by-step and utilizing the right tools will help the job go smoothly.

Here is a quick recap of the crown molding corner installation process:

1. Measure and cut the crown molding lengths
2. Miter or cope the corner pieces
3. Mount the molding on marked guidelines
4. Caulk, prime, and paint for a finished look

With proper materials, patience, and technique, you can tackle even the most complex crown molding projects. The finished molding will add instant elegance and style to your home’s décor for years to come.

Tool	Purpose
Miter saw	Precisely cutting crown molding angles
Coping saw	Cutting profile contours for coping
Nail gun	Securing molding to walls
Laser level	Marking installation guidelines
Filler	Filling nail holes and seams
Caulk	Sealing gaps and cracks

This table summarizes the main tools required for crown molding installation and their purposes in the process.

Installing crown molding in your home can seem like an intimidating task, but with proper planning and by following key steps, you can achieve beautiful results. Crown molding instantly elevates the look of any space by adding architectural detail, visual interest, and clean finished corners. While cutting the angles accurately takes practice, the final polished molding is well worth the effort for enhancing your home’s interior décor.