The Ins and Outs of Window Trim Installation

Posted by Brett McCutcheon on Jan 23, 2023 7:30:00 AM
Brett McCutcheon

window trim instillation

Whether you're restoring an old home or building a new one, window trim installation is a delicate task that requires precision work. It can however be made easier with knowledge and the right tools such as a finish hammer, hand plane, and miter saw for precise angle cuts. You might also need a table saw for general short length cutting.

One of your most important tools will be the installation nailer. The FASCO® (a BECK member) F30AT FN65 LM finish nailer is the right tool for the job. It delivers 16ga brads in the 5/8 to 2 9/16 range and comes with an extra-long magazine that can hold up to 150 brads for a smooth workflow without repeat reloading. It also comes with a rubber comfort grip that keeps your handling precise and slip-free. But one of its most important features, especially when it comes to trim, is its nose protection. It is designed to leave wood pieces free of marks, so your work will look clean and elegant.

Along with the proper tools, installation knowledge is the other key component to successful window trim installation. Here are some crucial tips to help!

Smoothing and Prepping Jambs

Your window jambs should be perfectly flush with their surrounding wall space and completely straight. To ensure that they are, hold a straightedge across your window to check for protrusions. If you find any, smooth them down using a wood plane. Preferably, use a hand-powered plane instead of an electric device because you can gently carve out layers of wood.

If on the other hand any jambs fall short of the wall edge, strip jamb extensions that are as wide as necessary from 1x wood stock and ¼ inch thinner than your jamb thickness. Then using your FASCO® F30AT FN65 LM finish nailer, drive 1 ½ inch 16-gauge brad nails in at intervals of a few inches. You can plane off any excess protrusion from the brad extensions.

Marking Trim Length and Angle

Expert window trim installers can often eyeball lengths so well that they don't even need to use a tape measure for cutting their trim angle lengths. If you're not as experienced, the simple trick is to cut one end of your trim at a 45-degree angle and hold it to your window frame so that the short end of the angle is flush against your window jamb.

Then on the other end, mark the point where the lower part of the trim touches exactly on the opposite edge of the window jamb. This will give you an exact spot for where you can make the opposing 45-degree angle cut. You can apply this technique all along the edges of your window where trim will be installed.

Always Check Fit Before Cutting

A basic rule of all fine carpentry and finish work is that you should measure twice and cut once. This applies especially to window trim, which must be precise and neatly fitted once installed. By using a miter saw, you can ensure precision trim angles and ruler-straight cut lines for your carefully measured lengths of trim. If there are any tiny gaps between trim joints, you can fill these with glue or putty and sand them down afterward.

Ensuring Proper Nail Spacing

When you have your pieces of trim cut to their right lengths and angles, they should fit snugly together with little or no gaps between them. Installing them is a matter of gluing them together and fitting them.

The glue will provide a temporary hold while you nail your trim into place permanently with finish nails, or 1-inch brad nails, that you space roughly 6 inches apart. If your trim is heavy-gauge, use 2-inch or slightly larger brads. The FASCO® F30AT FN65 LM finish nailer is particularly useful for this because of its brad length versatility.

Just be extra careful and nail them into the jamb before nailing them more firmly into the wall. This way, if you make any mistakes with fitting or measuring, you'll have two chances to remove and fix the trim pieces before permanently installing them.

Use Ideal Tools for Smooth Workflow

As we earlier stated, proper window trim installation is all about knowledge and the tools. The FASCO® F30AT FN65 LM finish nailer is particularly well designed for this work due to its versatility with different nail lengths, nose protection, and penetrating power. It also offers extra-long magazines for reloading less often. What's more, this particular nailer can be used for other wood projects such as furniture and millwork among others. Click below to learn more!The FASCO F30AT FN65 LM Finish Nailer

Topics: Nailers, bradders, framing, window installation, trim, finish nailer


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