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Endura Flap Thermo Panel 3e (1-Piece) - Installation Instructions

Installation Instructions

Click to view the Two-Piece Thermo Panel 3e Installation Instructions.

Installation icon Difficulty Easy
Installation icon Steps 06
Installation icon Time Required 0.5 hours
Installation icon Sections 02
Installation icon Flags 02


  • Panel Pet Door
  • Foam Weather Strip
  • Center Post Weather Seal Draft Stopper
  • Sliding Door C-Clamp Lock
  • Screwdriver


  • Flathead Screwdriver

Please read instructions & notes thoroughly before installation.

One-Piece Panel

Step 1 Adjust the Step Over (Optional)

  • The Endura aluminum sliding door panel has a patented Adjustable Step-Over feature which allows you to adjust the height of the flap to the most comfortable fit for your pet.
  • The top of the flap should be positioned to be at least 1” above the top of the pet’s shoulder.
  • If the factory setting is not suitable, please adjust it before proceeding. If the current setting is suitable, proceed to the “Installation Instructions” section.

Step 2 Adjust the Screws

  • Lay the entire panel on a flat surface.
  • Using a #2 flat head screwdriver, remove the bottom side-screws and loosen the upper side-screws. Screws were tightly installed to hold the panel together during shipping; a power tool* is recommended.
  • If you do not have a flat head drill bit skinny enough to fit, let us know and we’ll send you one for free.

Step 3 Adjust the Spacers

  • Once the bottom screws have been removed and the upper side-screws loosened, the Pet Door Assembly and spacers can be removed by sliding the sections down and out of the panel.

Step 4 Replace the Spacers

  • Replace the spacers and the Pet Door Assembly by sliding them back in a different order to achieve the desired height. You can move the spacer below and above the flap to raise or lower the flap height.
  • The order of the pieces is important! The piece on the bottom needs to always be at the bottom, as that is where the screws attach.
  • Make sure that the locking cover side of the flap frame is on the same side as the height adjustment locks.

Step 5 Tighten the Screws

  • When finished, replace the bottom side-screws and tighten the next upper-side screws.
  • A lower step-over height is easier for pets to navigate. However, if the top of the flap is low enough that the pet needs to crouch to get through their pet door, they can injure themselves and possibly cause the pet door to malfunction. If your pet door does not sit at a comfortable height for your pet, you may need a larger flap size.

Step 6 Unlock Spring Mechanism

  • Loosen the height adjustment locks at the top of the pet panel with the screwdriver. This allows the spring mechanism to move freely up and down.

Step 7 Test Fit the Panel in Your Track

  • You want to put the pet door in your track before applying any weather stripping to ensure it fits. If the panel fits well, proceed to the next step. See the FAQs if you have trouble.
  • To insert the panel into the top track, push up against the spring mechanism and swing the bottom of the panel up and over the threshold.
  • Seat the panel on top of the small guide rail in the track.
  • If you can’t quite get it in the track, try swinging in from the outside as the outside track wall may be shorter.

Step 8 Apply the Weatherstripping

  • Once you’re sure the panel fits, remove it from the frame and lay it on its side on the ground.
  • Apply the foam weather-stripping by peeling back the paper and exposing the adhesive.
  • Unroll it along the edge of the panel, pressing to ensure it adheres. Install on both sides, trim it fit with scissors.

Step 9 Install the Draft Stopper

  • The center post weather seal strip (draft stopper) should be installed on the inside of the home.
  • It can install on either the back edge of the sliding door panel or the leading edge of the stationary panel.
  • This strip prevents air from leaking between the sliding glass door and the stationary panel.
  • Trim with scissors as needed. Clean the edge of your patio door with rubbing alcohol before installing to assure a good seal.
  • Repeat step two to install the panel in your track.

Adjusting the Stepover Height

Variable Magnetic Resistance

Lock Details

a lock can secure your slider in place

Since you cannot lock your sliding door to your panel pet door, we have provided you with alternative locking methods to secure your home:

Installing the sliding door clamp: This clamp has a screw that tightens by hand to prevent the sliding door from moving beyond the clamp’s placement. For doors manufactured with the glass slider on the inside track, the lock can usually be installed on the door’s raised track.

If you aren’t able to use the lock that comes with the panel: A great alternative to locking your sliding glass door is a Charley bar or dowel in the track. Both work off the same concept – they block the slider from opening. When engaged you cannot pull the sliding door away from the pet door panel.

Other Installation Options

Semi-Permanent Installation:

You might choose to secure the panel in your track with screws. This can be done by drilling screws at an angle in the top and bottom tracks. We recommend doing this from the outside to minimize damage to the sliding glass door frame. One-way screws will prevent tampering or removal of the panel from the outside.

you can screw your panel into your slider for a more permanent installation

Stationary Panel:

Some stationary sliding door panels can be unfastened and moved over to one side so that you can install the pet door panel between the jamb and stationary panel.

Avoid damaging your sliding glass door by checking that your door can move and that you can reinstall it properly before trying to uninstall the unit.

You will still lose space in your slider to move through, however, you will be able to use your existing sliding door lock to secure your home. Installing your pet door this way is also great in that you already have an alarm system in place.

If your sliding glass door slides on the outside track, using an alternative lock might not be possible, so this allows you to still lock your door.

NOTE: You can do the stationary panel install with the regular spring actuator method – no need to screw it in.


What if my panel is slightly too tall?

You can trim up to 3/4" off the spring-loaded adjustment piece at the top. This can be done by removing the adjustment piece with a #2 Phillips head screwdriver and cutting down the flanges. Be careful not to cut too low of you will not be able to put the top back on.

What if my panel is slightly too short?

We offer height extensions that will add 3/4" to the top of the panel that you slide into the channel at the top. These are made from the same aluminum as the panel so you can match the color.

You can also make your extension out of 1" wood (which is 3/4" thick), such as a 1x3 if you need more than 3/4" in height.

Cut it to the same width as the panel and slide it into the channel at the top. Paint the wood to match your frame color. If the extension makes the panel feel unstable, you can secure it with screws.

What if hardware for the locking latch is preventing the door from sealing properly?

You might be able to remove the hardware, as in some cases they are only held in place with a couple of screws.

If you are not able to remove it you can try installing the panel on the stationary side as mentioned on page.

If neither of those choices works, you can try to shim the panel out so that it is even with the face of the lock. Depending on how far it sticks out you might be able to use a thicker foam weatherstripping or a small piece of wood between the panel and wall jamb.

My slider isn't closing evenly against the panel?

Your slider may not be level, which can happen in older houses. In that case, you may be able to adjust the wheels on the slider enough to line it back up. It will depend on your door, but you should be able to adjust a screw near the bottom of the door.

Turning the screw will adjust the wheels slightly. If the slider is level then it could be an issue with the metal height adjustment lock at the top of the panel. You can also use a rubber mallet to tap the curve into a straight line.

If the height adjustment lock is hitting the edge this can mean that the bottom of the panel is going further into the jamb that it can at the top. A gap appears that gets wider as you go down the panel. You can use wood shims or weatherstripping in the jamb to push out the bottom of the panel.

What if the panel is wobbling slightly back and forth?

If your track is wider than 1" you can use small wooden shims or extra weatherstripping to fill in the gap inside the top and bottom tracks. By placing the material inside the tracks you won't be able to see it, but it will stabilize the panel. You might also try semi-permanently installing the pet door.

The slider is on the outside track? How do I lock it?

This can cause an issue if you are trying to lock the door since the clamp lock, Charley bar, or dowel in the track won't really work. In this case, you can use a foot lock. The downside is that you have to drill that into the front end of the stationary panel frame as well as a small hole in the sliding door frame.

Depending on the handle of your slider, you might be able to put a Charley bar between the handle and the edge of the stationary. The slider would then push against the pet door and prevent someone from opening your door.

Alternatively, you can also try installing the pet door between your stationary glass and wall.

There is a large ste-down going out/coming in for the pet?

In this case, you can use a ramp or some small steps to minimize the height of the drop. You'll want the distance between the top of the flap and the ground to allow your pet to go through your flap without ducking or hitting their back.

What if I have an alarm system?

The alarm company might be able to come out and move the sensor for you. So instead of one part being on the door and the other on the jamb, you would end up having one side on the panel that matched up with the one on the sliding door.

As there are many different types of alarm configurations we would recommend that you always consult the alarm security company first to discuss your options.