Patio Pet Door Panel Installation in Monorail Track Sliding Glass Doors

patio pet door panels in silver and white - pet sliding door installation

Over the years, we have become accustomed to the traditional ‘U’ shaped tracks in most sliding glass doors models. The original Patio Pet Door Panels were designed with this style in mind. There is an emerging trend in sliding glass doors to eliminate the bottom ‘U’ shaped track (sometimes the upper one too) and replace it with a monorail-style track where the sliding door rides on top of the track instead of in a channel. Installing dog doors in sliding glass doors is hard enough, but if you have a monorail track, things get even harder! Read on for proper installation of patio door panels for monorails!

This new design presents challenges for the Patio Pet Door Panels which use the ‘U’ shaped track walls to hold the bottom of the panel in place. The monorail style requires the Patio Pet Door Panel to be secured to the track. This can be accomplished in one of two ways.

proper installation of patio door in monorail track requires an adaptor                                                       Monorail                          ‘U’ Shape

  1. You can toe-nail the bottom of the panel into the monorail track using screws - this becomes a semi-permanent installation.
    sliding door pet door adaptors - install dog door in sliding glass door
  2. For the Endura Flap Thermo Panel 3e, an adapter may be an option.  If your monorail is less than 3/4" thick, you can install the Thermo Panel 3e with this monorail adapter. This will be a custom installation requiring the use of a power drill and possibly a jigsaw. Once these modifications have been made, the panel will not be returnable. 

The adapter method will not put holes in the monorail but may take a little more handy work to install. The finished installation looks nice, is securely installed in place, and can be removed. Here are a couple of pictures of an Endura Flap Thermo Panel monorail sliding door installation.

                       how to install sliding door insert with monorail track    view of the sliding glass door bottom track for how to install a sliding door monorail panel

When measuring the track height for the monorail design, you will need to measure from the top of the bottom monorail to the highest point in the upper track. You'll also need to measure the thickness of the monorail itself.

Each manufacturer and model of sliding glass doors can be different.  If you need help understanding the differences, measuring, or purchasing the adapter, has a team of expert Customer Service Agents that can walk you through your options.  They’re available Monday- Friday, 7am - 4:30pm Pacific time for calls or online chats. Pictures can be useful in determining the best solution for your specific situation. You can email them to  


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