Installing Door Casing and Trim
Measure and mark reveal line 1/4 inch from door frame edge
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Tools Needed
- miter saw
- nail gun
- measuring tape
- level
- coping saw
- sandpaper
Parts & Materials
Available from multiple retailers
Available from multiple retailers
Available from multiple retailers
Available from multiple retailers
Available from multiple retailers
⚠️ Safety First
🔧 Tools Needed
📦 Materials
📋 Step-by-Step Instructions
1. Measure and mark reveal line 1/4 inch from door frame edge
2. Cut side casings to length with square bottom cuts
3. Cut 45-degree miter angles on top of side casings
4. Install side casings with finish nails into frame and wall studs
5. Measure and cut head casing with 45-degree miters on both ends
6. Test fit head casing against side casings for tight joints
7. Install head casing and check all joints
8. Fill nail holes with wood filler and sand smooth
9. Prime and paint casing to match existing trim
10. Caulk any gaps between casing and wall
💡 Pro Tips
❌ Common Mistakes to Avoid
🔍 Troubleshooting
Miter joints don't close properly
*Cause:* Angle not exactly 45 degrees
*Fix:* Adjust miter angle and re-cut
Casing proud of wall surface
*Cause:* Frame not flush with wall
*Fix:* Plane frame or add backing shims
Nail holes visible after filling
*Cause:* Nails driven too deep
*Fix:* Use matching wood filler and sand carefully
❓ Frequently Asked Questions
Q: Should I use nails or screws
A: Finish nails are standard for casing installation
Q: How wide should casing reveal be
A: 1/4 inch is standard, but can vary for design preference
✅ Checklist
Related Guides
Installing a Dead Bolt and Lockset
Mark the lock height (36 inches from floor is standard) and center on door edge
Read Guide →