Chair rail is the horizontal trim moulding that runs around a room at chair-back height (typically 32-36 inches). Originally functional (preventing chair backs from damaging walls), it's now decorative — adds architectural interest and creates a visual division between wainscoting/lower wall and upper wall paint.
This guide covers a typical chair rail installation with both inside-corner cope joints and outside-corner mitres.
Before you start
Two things to settle:
1. Height: 32-36 inches typical. Chair rail height is traditionally about 1/3 the height of the wall (so 32-36 inches on 9-10 ft ceilings). Keep height consistent throughout the home.
2. Cope inside corners, mitre outside. Same as baseboards. Inside corners cope to fit; outside corners mitre at 45 degrees.
What you'll need
Tools
- Mitre saw
- Coping saw
- Tape measure and pencil
- Stud finder
- Brad nailer
- Caulk gun
- Sander or sanding block
Materials
- Chair rail moulding (length + 10% waste)
- 18-gauge brad nails
- Wood filler
- Painter's caulk
- Primer and paint
Mark a level reference line first
Walls aren't perfectly level top to bottom. Mark a horizontal level line all the way around the room at the planned chair rail height. Install all pieces to this line, regardless of variations in wall geometry.
Step-by-step instructions
Mark the level reference line
Pick height (32-36 inches typical). Use a 4-foot level to mark a horizontal line at this height around the room.
For long walls, use a laser level for continuous reference.
Find studs
Sweep walls with stud finder. Mark stud locations along the chair rail line.
Plan to nail into studs every 16 inches plus at piece ends.
Cut and install first piece
First piece: square cuts at both ends (no mitre, no cope). Length spans wall corner to corner.
Position with top edge on reference line. Nail to studs.
Cope inside corners
Second piece: cut 45-degree mitre at end meeting first piece. Cope along profile with coping saw.
Test fit. Adjust until cope sits tight against first piece's face.
Continue around room
Inside corners cope. Outside corners mitre at 45 degrees.
Verify chair rail is level along each piece's installation.
Fill nails, caulk seams
Fill brad holes with wood filler. Sand smooth.
Caulk top and bottom edges where moulding meets wall — hides gaps from wall variations.
Prime and paint
Apply primer if raw wood. Two coats of trim-grade paint.
Often painted same colour as baseboards and crown for unified look.
Common mistakes that cost you
- Inconsistent height. Chair rail not at uniform height looks unintentional. Use level reference line throughout.
- Mitring inside corners. Joints open up over time. Always cope inside.
- Nailing only into drywall. Pulls free over years. Anchor into studs.
Frequently asked questions
Should I add wainscoting below the chair rail?
Optional. Chair rail alone provides architectural detail. Wainscoting (panelling below the rail) creates a more formal traditional look.
Match style to home — modern homes typically don't use wainscoting; traditional homes often do.
When to call us instead
Chair rail is part of full trim packages. We do trim throughout renovations as part of fixed-price work.
Book a free 60-minute site visit →Related Ottawa services
If you're updating trim throughout, our residential renovation team handles trim consistently. Book a free 60-minute consultation.