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Thermo Sash 3e Cat Door for Sash Windows

Regular price
$419.99
Sale price
$419.99
Unit price
per 
White
Bronze
Brushed Aluminum

  • Durable and insulating pet door for windows
  • Dual-pane, Low-E glass for energy efficiency and reduction of harmful UV and infrared light
  • Sturdy aluminum framing
  • Various colors and adjustment ranges to fit your pet and your window
  • Strong Locking Cover included to secure your home and cat
  • No tools required for installation, perfect for renters and vacation homes
Holds Up to Harsh Weather Holds Up to Harsh Weather
Cats Love it Cats Love it
Tool-Free, Five Minute Installation Tool-Free, Five Minute Installation

Product Details

  • Highly insulating flap with a complete magnetic seal, designed to stay closed in winds up to 50mph
  • Polyolefin-based polymer flap keeps your home comfortable in temperatures between -40 and 110℉
  • Dual-pane, Low-E glass gives you extra insulation for your home, pairs perfectly with newer energy-efficient windows
  • Fits all vertical sliding sash window widths between 22" - 43" with a track width of at least 1"
  • Three color options including white, brushed aluminum, and bronze (very dark brown)
  • Includes a draft stopper and weatherstripping for extra insulation and weather resistance
  • Can be installed and removed in seconds due to the spring-loaded design, no tools required
  • 100% made in the USA

There has been lots of discussion as to why the Endura Flap is such a‚ high-performing pet door, but for engineers or those looking for some more technical information here is a 74-page‚ dog door energy efficiency study‚ showing what makes it so special.

Need help Installing? Take a look at our Thermo Sash Installation page.

Parts List

Thermo Sash 3e

1 window pet door

1 locking cover

1 center post weather seal draft stopper

1 foam weatherstrip

1 installation instruction booklet

Parts and Accessories

 

Size Chart

Flap Size Flap Dimension Height To Raise Window
Small 6" w x 11" h 18 1/2"

Adjustment ranges:

22"– 25", 25"– 28", 28"– 31", 31"– 34", 34"– 37", 37"– 40", 40"– 43"

Important Note: All Extra Large and 22"-25" adjustment range sales are final, no returns. Please simulate the opening (open the window, use duct tape to simulate the opening) to be sure this size is appropriate before ordering.

Installation Instructions

PARTS & TOOLS

1x Window pet door

1x Foam Weather Strip

1x Center Post Weather Seal Draft Stopper

INSTRUCTIONS 

Step 1: Loosen the thumbscrews at the end of the sash. This allows the spring mechanism to move freely side to side.

Step 2: Insert the sash into the window track. Push against the spring mechanism and swing the opposite end into the opposite window track. Gently release. Tighten the thumbscrews.

If the pet door sits properly, remove the pet door to put on the foam weather-stripping in step 3.

Step 3: 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 the top and the bottom. Trim to fit with scissors.

Step 4: Mount the draft stopper vinyl weatherstrip. This strip prevents air from leaking between the window frame when raised to accommodate the sash. Trim to fit with scissors.

LOCKING YOUR WINDOW

For a permanent lock, install a wood screw in the track immediately above the window on both sides. You will no longer be able to raise the window.

For a temporary lock, place a removable wooden dowel or Charley bar in either track above the window.

SWITCH SIDE OF FLAP

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. 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 thumbscrews. Replace the end spacer and screws.

HEIGHT OF YOUR WINDOW

Make sure you place steps or ramps leading to your pet™s door at a height that works! When they go through the flap, the top of the flap should be at least 1" (2,5 cm) higher than the top of their back. Watch your pet and adjust as needed to keep them comfortable.


Videos

Installing a Thermo Sash 3e


How to Measure Your Door for a Sash Window Pet Door


Variable Magnetic Resistance


Replacing the Flap in the Sash Pet Door


Switching Flap Sides


Wind Test

FAQ

Does the Thermo Sash have an adjustable height?

No, the height of the unit is determined by the height of the pet door.

Can I still into this dog door into my window if my window is not at ground level?

Yes! You can install steps or a ramp on both sides of the window to ensure your dog has access.

Is there a way to switch which side of the Thermo Sash the flap is on (from the left to the right)?

Yes. Start by removing the screws on the bottom and top og the panel, then sliding the flap assembly out. Then you can simply flip the assembly upside down and slide it right back in. Put the screws back in and tightened them. Make sure the thumb screws and your locking cover are on the same side of the panel.

Is the Thermo Sash available in sizes narrower than 22” wide?

You can make the panel ¾” smaller by trimming the spring loaded piece on the right side. Otherwise, we may be able to make you a custom unit. Please contact customer service for more details.

How high does my window have to be raised in order to install the Thermo Sash?

It varies based on your pet door size and height:

  • Small is 19"
  • Medium is 23"
  • Large is 27"
  • Extra Large is 31"

What is the minimum width of the window track needed to accommodate the Thermo Sash 3e?

Your window track must at least be 1” wide. Your window track must be at least 1 inch wide for thermo sash 3e pet door installation.

Which Thermo Sashes are considered custom and are not returnable?

All Extra Large pet door sashes and any pet door size in a sash width with a 22"-25" adjustment range.

Warranty

Endura Flap products have a lifetime warranty against defects in materials and workmanship under standard regular use. Damage caused by not using the product as intended, improper installation, and chewing is not covered under this warranty.

Customer Reviews

No reviews yet Write a review

Thermo Sash 3e Cat Door for Sash Windows

White / 22-25 Edit

The Thermo Sash window dog door is aethsetically pleasing and build to last. It comes in a variety of sizes to fit many animals.

Size Chart

Flap Size Flap Dimension Height To Raise Window
Small 6" w x 11" h 18 1/2"

Adjustment ranges:

22"– 25", 25"– 28", 28"– 31", 31"– 34", 34"– 37", 37"– 40", 40"– 43"

Important Note: All Extra Large and 22"-25" adjustment range sales are final, no returns. Please simulate the opening (open the window, use duct tape to simulate the opening) to be sure this size is appropriate before ordering.

Installation Instructions

PARTS & TOOLS

1x Window pet door

1x Foam Weather Strip

1x Center Post Weather Seal Draft Stopper

INSTRUCTIONS 

Step 1: Loosen the thumbscrews at the end of the sash. This allows the spring mechanism to move freely side to side.

Step 2: Insert the sash into the window track. Push against the spring mechanism and swing the opposite end into the opposite window track. Gently release. Tighten the thumbscrews.

If the pet door sits properly, remove the pet door to put on the foam weather-stripping in step 3.

Step 3: 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 the top and the bottom. Trim to fit with scissors.

Step 4: Mount the draft stopper vinyl weatherstrip. This strip prevents air from leaking between the window frame when raised to accommodate the sash. Trim to fit with scissors.

LOCKING YOUR WINDOW

For a permanent lock, install a wood screw in the track immediately above the window on both sides. You will no longer be able to raise the window.

For a temporary lock, place a removable wooden dowel or Charley bar in either track above the window.

SWITCH SIDE OF FLAP

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. 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 thumbscrews. Replace the end spacer and screws.

HEIGHT OF YOUR WINDOW

Make sure you place steps or ramps leading to your pet™s door at a height that works! When they go through the flap, the top of the flap should be at least 1" (2,5 cm) higher than the top of their back. Watch your pet and adjust as needed to keep them comfortable.


Videos

Installing a Thermo Sash 3e


How to Measure Your Door for a Sash Window Pet Door


Variable Magnetic Resistance


Replacing the Flap in the Sash Pet Door


Switching Flap Sides


Wind Test

FAQ

Does the Thermo Sash have an adjustable height?

No, the height of the unit is determined by the height of the pet door.

Can I still into this dog door into my window if my window is not at ground level?

Yes! You can install steps or a ramp on both sides of the window to ensure your dog has access.

Is there a way to switch which side of the Thermo Sash the flap is on (from the left to the right)?

Yes. Start by removing the screws on the bottom and top og the panel, then sliding the flap assembly out. Then you can simply flip the assembly upside down and slide it right back in. Put the screws back in and tightened them. Make sure the thumb screws and your locking cover are on the same side of the panel.

Is the Thermo Sash available in sizes narrower than 22” wide?

You can make the panel ¾” smaller by trimming the spring loaded piece on the right side. Otherwise, we may be able to make you a custom unit. Please contact customer service for more details.

How high does my window have to be raised in order to install the Thermo Sash?

It varies based on your pet door size and height:

  • Small is 19"
  • Medium is 23"
  • Large is 27"
  • Extra Large is 31"

What is the minimum width of the window track needed to accommodate the Thermo Sash 3e?

Your window track must at least be 1” wide. Your window track must be at least 1 inch wide for thermo sash 3e pet door installation.

Which Thermo Sashes are considered custom and are not returnable?

All Extra Large pet door sashes and any pet door size in a sash width with a 22"-25" adjustment range.

Warranty

Endura Flap products have a lifetime warranty against defects in materials and workmanship under standard regular use. Damage caused by not using the product as intended, improper installation, and chewing is not covered under this warranty.

Customer Reviews

No reviews yet Write a review

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