Dragon Sash Window Pet Door - Installation Instructions

Installation Instructions

installation video image
Installation icon Difficulty Easy
Installation icon Steps 04
Installation icon Time Required 0.5 hours
Installation icon Sections 03
Installation icon Flags 01


  • 1 Sash Window Insert with a Pre-Installed Single Flap Dragon Pet Door
  • 1 Foam Weather Strip
  • 1 Locking Cover


  • Flathead Screwdriver

Please read instructions & notes thoroughly before installation.

Step 1 Release Spring Mechanism

  • Loosen the width adjustment locks at the end of the sash with a screwdriver. This allows the spring mechanism to move freely from side to side.
  • Watch out, it might jump at you the first time.

Step 2 Test Fit in Window Track

  • Before applying weatherstripping, insert the sash into the window track to test he fit.
  • Push into the spring mechanism and swing the opposite end into the opposite window track. Gently release then tighten the width adjustment locks.
  • Ensure that the pet door sits correctly in the window. See the FAQ for guidance if the sash does not quite fit.

Step 3 Apply Weather-Stripping

  • Once you have confirmed the sash fits, loosen the width adjustment locks and remove it from the frame.
  • Apply the foam weatherstripping by peeling back the paper and exposing the adhesive. Unroll it along the edge of the sash, pressing to ensure it adheres.
  • Use scissors to trim the strip to fit the length of your sash. Apply to both the top and the bottom.

Step 4 Lock Into Track

  • Place the sash back into the window, then tighten the width adjustment locks to lock it in place.


For a temporary lock, place a removable wooden dowel or charley bar in either track above the window, shown here. For a permanent lock, install a screw in the track immediately above the window on both sides. You will no longer be able to raise the window.


What if my window is slightly too narrow?

The sash can be trimmed up to 3/4” in cases where it is a bit too wide to fit into the track. Remove the spring-loaded adjustment pieces using a #2 Phillips head screwdriver. Using a clamp and a flat surface, cut off the flanges using a jigsaw with a metal cutting blade. You can also use a hacksaw, though it is more labor intensive and you may end up with a less clean cut. The dark area marks where you can trim:

What if my window doesn’t open enough?

Some windows will have stops that prevent them from fully raising up. In some cases, these can be removed allowing it to go up far enough to get the sash in place. You want to be careful when removing them, as it could damage the window or void the window’s warranty.

What if the track is too narrow for the pet door?

The spring adjustment pieces are slightly wider than the rest of the pet door, which may prevent it from fitting in the track. There are several potential solutions. One, you can trim one of the flanges off the spring-loaded adjustment piece, turning the "U" shape at the end into an “L". Alternatively, you can remove just one of the adjustment pieces with a Phillips head screwdriver and add shims for a snug fit.

You could also use a small piece of board in the channel of the adjustment piece, shown here. This board can be thinner and extend into the track giving the tension you need to hold it in place. Last option would be to install the sash using brackets to screw it into the track. Brackets would need to be made or purchased from your local hardware store.

What can I do if the track is wider than the pet door?

If the track is too wide to support the sash upright, you can use foam weather stripping or shims inserted into the track on the sides and/or bottom to fill up any of the gaps causing it to wobble. For a more permanent option, you can toe nail the sash into the framing with screws.

Switch the Side of the Flap

You can switch which side of the sash panel the pet door flap is on to best fit your home.

Step 1

  • Remove the screws on the top and bottom closest to the edge of the pet door. Then slightly loosen the screws closest to the glass. Next, slide off the side piece, then the flap assembly.

Step 2

  • Rotate the flap assembly (essentially flipping it upside down) then slide it back in. Make sure the locking cover is on the same side as the width adjustment locks.

Step 3

  • Replace the end spacer and screws.