Corner trim, that seemingly small detail, can elevate a space from basic to beautifully finished. But those crisp mitered corners that professional carpenters seem to achieve effortlessly can be tricky for DIYers. Fear not! With the right approach and some pro tips, you can install corner trim that looks polished and precise. Preparation is key. Before you grab your saw, take time to measure meticulously. Measure each wall where the trim will go, noting any doorways or windows that require adjustments. It is always better to err on the side of having a little extra trim, so factor in about 10% for mistakes or unforeseen cuts. Once you have your measurements, sketch out a layout on paper to visualize how the pieces will fit together. This helps identify any potential problem areas before you start cutting. Now, onto the fun part – cutting the trim. Invest in a good quality miter saw for clean, accurate cuts.  A dull blade will result in ragged edges, so make sure yours is sharp.  For outside corners, which are the most visible, use a 45-degree miter on each piece of trim to create a perfect 90-degree angle when joined.

Here’s a professional trick:  think left over right when making your cuts. This means placing the left side of the trim piece against the saw for the first 45-degree cut, and the right side for the second. This ensures the correct angle for a tight outside corner fit. For inside corners, the opposite applies. Here, you will need two 45-degree cuts mirrored on each piece, with the left over left and right over right technique.  This creates a pointed end on each piece that, when joined, fits snugly into the corner.  Dry fitting your cuts before securing them is crucial. Hold the pieces together at the corner and check for any gaps or misalignments. If needed, make slight adjustments to your cuts until everything fits perfectly. Once you are happy with the dry fit, it is time to secure the trim. Professionals often use a combination of nail guns and glue for a strong and lasting hold.  A finish nail gun will allow for precise nail placement, minimizing the chance of splitting the wood. Apply a thin bead of wood glue along the back of the trim piece before nailing it into place. This glue adds an extra layer of security and helps prevent the trim from popping loose over time.

When nailing, aim for the corner trim where the two 45-degree cuts meet. This hides the nail heads and creates a clean appearance.  For outside corners, it is helpful to pre-drill small pilot holes to prevent the wood from splitting.  Set the depth of your nail gun so that the nails sink slightly below the surface of the wood. This allows for easier filling and creates a smoother finish. After the trim is secured, it is time to address any nail holes and imperfections.  Use a filler specifically designed for wood. Apply a small amount with a putty knife, pressing it gently into the hole. Once dry, sand the filled areas smooth with fine-grit sandpaper.  For a flawless finish, lightly sand the entire length of the trim to remove any minor scratches or roughness. Finally, painting the trim ties the whole project together.  Opt for a high-quality paint specifically formulated for trim. Apply a light coat with a fine-tipped brush, focusing on getting into the corners and detailed areas.  Two thin coats are better than one thick coat, as this helps to minimize drips and brushstrokes.