Installing the Interior Threshold on a Sliding Glass Door

  • 2-4 hours
  • Beginner
  • 35-100
What You'll Need
Measuring tape
Piece of wood
Electric drill
Wood screws
Caulk (optional)

Sliding glass doors were an upgrade to your living room, now you need the details to complete that project by installing the interior threshold as well. Thresholds are a piece of solid wood that work to keep the elements and insects from entering your home through the opening at the bottom of your door. Sliding doors don’t really have an opening at their bottom but thresholds are installed usually to protect feet from stepping on the metal frames that hold up the sliding doors or to bridge gaps between the flooring and the door frames.

Step 1 – Measuring

Take a measuring tape and measure the depth and width of the space that exists between your flooring and the sliding glass door frame. You must buy or custom-make a threshold that fits the measurements that you take. Although there are many different types of thresholds used by homeowners such as aluminum, wood, faux stone, and marble, this article will be only talking about wooden thresholds. Thresholds also vary by style, shape and purpose of use (indoor and outdoor uses).

Step 2 – Fitting

Try to fit in the interior threshold into the space for which it was made. It should fit snugly but not so tight that you must bang on it to fit it. Once you are confident that your interior threshold is the right size for the gap, bring it back out and make pencil markings evenly spaced out on the top portion of the threshold. Drill shallow holes using your electric drill over pencil markings you’ve just made.

These drill marks will help you so that you can pound nails in at these locations, securing your threshold later on. Also, while you are trying out the interior threshold in the gap, try and see if there are any chunks of dust, dirt or debris that would otherwise impede your threshold from its snug fit. Take a small hand-held vacuum cleaner, hold it over the gap and suck up any small particles before nailing down the threshold.

Step 3 – Securing

Place your interior threshold in the gap between the sliding door’s metal frame and the flooring. There are also different kinds of flooring that you could be working with, mainly carpeting and hardwood. Hardwoods are generally easier to find measurements for and to fit. When carpeting gets in the way of securing thresholds, it might be necessary to tear out a portion to make room for the threshold.

Also, a part of the carpet would need to go under the threshold to ensure an even borderline. You would have to keep this in mind when measuring the depth of the threshold. Now secure your threshold by drilling in screws. Since this is an interior threshold, you can opt to caulk it or not. Caulk would seal it from water damage and/or dirt.