Tools and Materials
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Before You Begin
The following instructions are intended to provide a general overview of how to install door trim and window trim moulding, including steps for removing existing window and door trim, installing new trim and applying the finishing touches to complete the project. Keep in mind that your steps may vary greatly depending on the type of trim and whether you’re installing it as part of a major home renovation or a simple refresh. If you’re unsure at any point, it’s always best to contact a professional.
Installing Window and Door Moulding
Follow these steps to upgrade window and door trim.
Step 1: Remove Any Existing Trim
Before you can install new window or door trim, you’ll first need to take off the old trim. You’ll need a utility knife, a hammer and moulding pry bar for this step. Run the utility knife along the seam between the moulding and wall. Press firmly to cut through any paint.
Next, slide the pry bar between the trim and wall. Tap it gently with the hammer to loosen the trim on all sides of the window or door frame and carefully pull the trim away from the wall.
Step 2: Fill In Gaps
After removing the old trim, check for gaps around the window or door frame. If you find any, use wood filler or caulk to fill them in. Apply the wood filler or caulk with a putty knife for an even layer and allow it to dry according to the manufacturer’s instructions. Sand the area using fine-grit sandpaper (120-grit or finer) for a smooth, clean surface. Wipe away any dust using a cleaning cloth.
Step 3: Mark the New Trim Location
Before you install new trim, you’ll need to mark what are referred to as reveal lines on the window or door jamb. If the new trim is placed flush against the inside edges of the jamb, small gaps can appear over time due to the wood expanding or contracting with the seasons or the house settling. Positioning the trim slightly away from the inside of the jamb edge can account for these changes.
To mark reveal lines, use a tape measure and a pencil. Mark the jamb about one-eighth to one-quarter inch from the inside edge on all sides of the window or door. These marks will act as a guide when you’re fitting the trim.
Step 4: Measure and Cut the Trim Pieces
Start by measuring the top and sides of your window or door frame. Use a miter saw to cut the moulding ends at 45-degree angles for clean corners. Always double-check your measurements before cutting. As the old woodworking adage goes, “measure twice, cut once.”
Step 5: Test Fit the Pieces
Before nailing the trim in place, hold the moulding pieces up to the window or door frame to make sure they fit snugly. You’ll likely need a helper for this step. If necessary, mark and trim the pieces for a tight, even fit.
Step 6: Attach the Moulding
Once you’re satisfied with the fit, use finish nails or a finish nailer to secure the moulding to the jamb, following the reveal lines. Start with the top piece, then add the sides. Use a level as you work to make sure everything stays straight and aligned.
Using a laser level as opposed to a standard level can make the job faster and easier.
Step 7: Fill and Caulk
Fill any nail holes with wood filler, then smooth the surface once it’s dry. Run a thin bead of caulk along the seams where the moulding meets the wall to hide gaps and create a seamless finish.
Step 8: Paint the Trim If You Like the Look
For a finished look, paint the moulding to match your other trim or décor. Allow it to dry completely before reinstalling any door hardware or window treatments. If you’re upgrading an exterior door, this is also a good time to increase your energy efficiency and keep out drafts by installing a door sweep.
Are you upgrading your door and window trim as part of a home refresh? Check out our guide for painting a wall, trim and ceilings for additional help.
Pro Tips for Installing Window and Door Trim
- Using a level helps you keep the moulding straight and level.
- Using a nail gun can help you get the job done quicker and easier.
- Taking your time and double-checking the measurements helps ensure a proper fit.
- Having a helper hold the moulding in place while you secure it can make installation easier and more accurate.
Key Takeaways: How to Install Window Trim and Door Trim
With the right tools and materials from Lowe’s, along with our easy-to-follow step-by-step instructions, DIYing can be a worthwhile and enjoyable experience. Here are the main points to remember as you plan for your project.
- Adding moulding gives windows and doors a clean, finished look.
- Gather tools like a miter saw, nail gun, hammer, caulk gun, putty knife and level before starting your project.
- Remove old trim carefully using a utility knife, hammer and small pry bar.
- Fill any gaps around the frame with wood filler or caulk and sand smooth.
- Measure and mark reveal lines to ensure proper alignment.
- Cut moulding at 45-degree angles for neat corners and test fit before nailing.
- Secure trim with finish nails or a finish nailer and check alignment with a level.
- Fill nail holes, apply caulk along seams, and paint or stain to finish.
- Use safety gear like gloves, eye protection and a respirator during installation.
- Work with a helper to make fitting and securing the moulding easier.
FAQ: How to Install Window and Door Trim
Here are some common questions Lowe’s customers have when installing trim for windows and doors.
What Tools Do I Need to Install Window and Door Trim?
You’ll need a few basic tools to get started: a miter saw, hammer, nailer, pry bar, measuring tape, caulk gun, putty knife, level and utility knife. Safety gear such as gloves and eye protection is also necessary.
How Do I Remove Old Window or Door Trim?
Start by running a utility knife along the edge where the trim meets the wall to break the paint seal. Then gently pry the trim away using a hammer and moulding pry bar. Take your time to avoid damaging the wall and frame.
Should I Caulk Around Window and Door Trim?
Yes, applying a thin bead of caulk along the seams where the trim meets the wall helps fill small gaps and creates a clean, professional finish. It also helps seal out drafts and moisture.