How To Replace Trim Around Interior Door

How To Replace Trim Around Interior Doors

Replacing interior door trim is a common home improvement project that enhances aesthetics and can increase property value. This article provides a step-by-step guide for replacing door casing, offering a clear pathway to achieve professional-looking results.

Tools and Materials: Before beginning, gather the necessary tools and materials. These include a pry bar, hammer, safety glasses, measuring tape, pencil, coping saw (optional), miter saw, wood glue, finishing nails, nail set, wood filler, sandpaper, paint or stain, and caulk.

Step 1: Removing the Existing Trim: Start by scoring the caulk line between the existing trim and the wall and door jamb using a utility knife. This prevents the paint from peeling during removal. Gently insert the pry bar behind the trim, working your way around the perimeter. Small blocks of wood placed between the pry bar and the wall help distribute pressure, preventing damage to the wall surface. Carefully remove all pieces of the trim – the two side casings and the header piece.

Step 2: Preparing the New Trim: Measure the height of the door jamb for the side casings. Add the desired reveal (typically 1/8 inch) to this measurement. Cut the new side casing pieces to this length using a miter saw. For doors with standard head casings, a 45-degree angle cut is typically used where the side casing meets the header. More elaborate trim styles may require different angles or decorative cuts.

Step 3: Installing the Side Casings: Apply a thin bead of wood glue to the back of the side casing pieces. Place the casing against the door jamb, ensuring the reveal is consistent along the length of the jamb. Secure the casing with finishing nails, spaced approximately 8-12 inches apart. Use a nail set to countersink the nail heads below the surface of the trim.

Step 4: Measuring and Cutting the Header: Once the side casings are installed, measure the distance between the outside edges of the two side casings at the top of the door frame. This measurement will determine the length of the header piece. Transfer this measurement to the new header piece.

Step 5: Mitering the Header (Standard Trim): For standard trim installations, use a miter saw to cut 45-degree angles at each end of the header piece. The angle should slope downwards towards the inside edge of the header. Ensure accurate measurements and cuts for a tight, professional-looking fit.

Step 6: Coping the Header (Alternative Method): Coping the header is a technique that provides a seamless joint, especially beneficial when walls are not perfectly square. Instead of mitering, one side casing is cut square. The mating header piece is then cut using a coping saw to match the profile of the side casing. This creates a tight, interlocking joint that accommodates irregularities in the wall.

Step 7: Installing the Header: Apply wood glue to the top edge of the side casings and the back of the header piece. Position the header against the side casings, ensuring a snug fit. Secure the header with finishing nails, countersinking the nail heads.

Step 8: Filling Nail Holes and Finishing: Apply wood filler to all nail holes and any gaps between the trim and the wall or door jamb. Once the filler is dry, sand smooth with fine-grit sandpaper. Clean any dust or debris from the trim.

Step 9: Painting or Staining: Apply paint or stain to the trim according to the manufacturer's instructions. Multiple coats may be required for optimal coverage and a professional finish. Allow sufficient drying time between coats.

Step 10: Caulking: Apply a thin bead of caulk along the seams where the trim meets the wall and door jamb. This seals the gaps, preventing air drafts and moisture intrusion. Smooth the caulk bead with a damp finger or caulk tool for a clean, professional look.

Dealing with Irregular Walls: Older homes often have walls that are not perfectly plumb or square. Shims can be used behind the casing to create a straight surface and ensure a consistent reveal. Flexible caulk can help fill larger gaps and create a seamless appearance.

Choosing the Right Trim: A variety of trim materials are available, including wood, MDF, and PVC. Consider the style of your home and the desired level of maintenance when selecting the trim material. Wood offers a classic look but requires regular painting or staining. MDF is a cost-effective option, while PVC is moisture-resistant and ideal for areas prone to humidity.

Safety Precautions: Always wear safety glasses when using power tools. Exercise caution when using sharp tools like utility knives and coping saws. Ensure adequate ventilation when working with paint, stain, or caulk.