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Endura Flap Thermo Sash 3e Cat Doors for Sash Windows

Regular price
$419.99
Sale price
$419.99
Regular price
Sold out
Unit price
per 
White
Bronze (Black)
Brushed Aluminum


  • Energy efficient cat door for windows with dual-pane, Low-E glass
  • Installs in sash windows 22" - 43" in width and at least a 1" thick track
  • Spring-loaded design does not require any tools for installation
  • Flexible flap remains secure and reliable in -40 degrees Fahrenheit temperatures and 50 mph winds
  • Locking cover included that loads from the top
  • Available in white, brushed aluminum, or bronze (black)

Product Details


For people who don't have the option of installing a cat door in a door or wall, the Thermo Sash Cat Doors for Windows provide a simple fix without any permanent alterations to your home. These window cat doors feature a highly insulating, weather-tight panel that installs into a wide range of sash windows without the need for any tools. No matter the season, your cat can experience free range without compromising your home's insulation in severe weather conditions.  If you need a larger flap size you will find them on the Endura Flap Thermo Sash 3e Pet Doors for Sash Windows page.

Features:

  • Extruded aluminum frame fits into windows from 22" - 43" in width and at least a 1" thick track.
  • Tool-free installation with spring-loaded design.
  • Dual-pane, Low-E glass panel ensures insulation and protects against harsh UV and infrared light.
  • Environmentally friendly, polyolefin-polymer flap stays securely sealed in 50 mph winds and -40 degrees Fahrenheit temperatures.
  • 6" x 11" flap size and adjustable step-over height accommodate cats of all breeds and sizes.
  • Adjustable magnets line the three sides of the flap for a tight, weatherproof seal. To adjust the magnet strength for easier training, refer to the 'Videos' tab for a short tutorial.
  • Includes a durable, ABS plastic locking cover that loads from the top
  • Foam weather stripping and a draft stopper included for optimized insulation.

 

Benefits:

  • Removable design is ideal for vacation homes and rentals.
  • Avoid any permanent alterations of your home's construction.
  • Flexible flap does not pinch or snag during use.
  • Durability and thermal quality of the panel ensures longevity and eliminates heating/cooling loss.

Size Chart

Flap SizeFlap DimensionHeight to Raise Window
Small6" x 11"18 1/2"

  

Adjustment Ranges:

  • 22" - 25" Custom Order
  • 25" - 28"
  • 28" - 31"
  • 31" - 34"
  • 34" - 37"
  • 37" - 40"
  • 40" - 43"

 

Pet door has 1" framing, measure your track width to make sure that your window will accommodate the sash.

Final Sales: Adjustment Range 22" - 25" are final sale and cannot be returned. Final Sale products are made to order and will take extra time to ship.

 

Additional Information

Flap Material

Flexible

Your Maximum Pet Size

Cats

Installation Instructions

Installing the Thermo Sash 3e




sash window pet door diagram

PARTS

  • 1x Sash Window Pet Door
  • 1x Foam Weather Strip
  • 1x Center Post Weather Seal Draft Stopper

INSTALLATION INSTRUCTIONS

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

inserting the sash into the window track

Step 3: Apply the foam weather-stripping by peeling back the paper and exposing the adhesive. Unroll it along the edge of the sash, pressing to ensure it adheres. Install on both the top and the bottom. Trim to fit with scissors.

applying the foam weather stripping

Step 4: Mount the Center Post Weather Seal Draft Stopper. This strip prevents air from leaking between the window frame when raised to accommodate the sash. Trim to fit with scissors.

mounting center post weather seal draft stopper

LOCKING YOUR WINDOW

permanent lock option

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, shown in Detail 1.

switching the side of the flap

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.

removing a pet door flap

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.

setting flap back in

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.

adjusting window height for sash pet door

Videos

How to Measure Your Sash Window for a Pet Door





Design of the Endura Flap





Adjusting Magnet Strength for Training





Leaf Blower Test


FAQ

What do I need to know/measure before I order?

First raise up your window and check that it can go up far enough to be left with an opening 18 1/2" high. Next measure the width of the track from left to right, including going inside the track on both sides. Last measure how wide the track is that the window slides in (needs to be at least 1")

How wide does the track have to be for the Thermo Sash 3e to fit?

Track width needs to be at least 1" thick.

Can I choose what side the door is on?

It comes standard on the left, if you are looking from the inside of the house. You can switch it to the other side if you need and that only requires a screwdriver.

Is this easy to install?

This is designed to be a fairly simple install that does not require any tools. Take a look at the video under the installation tab to see if it something you would be able to do.

Will this door be good for more extreme weather?

The Thermo Sash 3e has the Endura Flap which is far better in sealing and durability than other models. Dual pane lo-e glass offers superior insulation value. Therefore, the Thermo Sash will be a much more reliable and longer lasting option then the more inexpensive options.

Is it possible to make one that fits a window smaller than 22"?

We can, the only thing is that we would not be able to use glass so there would be quite a bit of aluminum and some customers are not happy with the aesthetics. This would also fall under the custom and non-returnable category.

My cat is having a hard time opening the flap is there something I can do that would make it easier?

You can by removing some of the magnets. On the videos tab check out the "Adjusting Magnet Strength for Training."

What if I mis-measured?

If you've mismeasured, you may be able to fix it. To make your sash cat door about 1" wider, you may purchase a width extension (or make your own using 1" x lumber). To make your window kitty door insert slightly shorter you may trim the side flanges on the spring loaded adjustment piece with a hacksaw or a jigsaw with a metal cutting blade.

What does custom mean?

Any of the Thermo Sash doors with "Custom" listed means that the door is built to order and therefore it is non-returnable.

Can I get a custom height?

We can only do custom widths, not custom heights.

Warranty

Patio Pacific Inc Endura Flap Pet Door Lifetime Warranty

The Endura Flap lifetime warranty guarantees that any defective parts returned with proof of purchase will be replaced by the manufacturer for free. This excludes damage caused by accident, improper installation, overuse, or misuse—including damage by pets or glass breakage.



Customer Reviews

Customer Reviews
4.8 Based on 20 Reviews
Write a Review

Thank you for submitting a review!

Your input is very much appreciated. Share it with your friends so they can enjoy it too!

Filter Reviews:
T
12/05/2017
tay
very nice

works like a charm, measuring was a little difficult to make sure everything was ready to go. It keeps everything well insulated, love the high quality of the glass and flap. It is air tight!

P
11/16/2017
Patty
Wonderful product

My husband and I are so happy with this cat door! We have two cats that just turned a year old. We let them go outside during the daylight hours when we are home. I was constantly letting them in and out, or leaving the back storm door propped open, letting the flies and neighbor cats in as well. My husband did not want a pet door, but I convinced him to give this one a try since no holes were drilled in walls or doors. I was able to easily install the window by myself following the video instructions, adding some shims (provided) to make everything line up, and also some insulation strips (provided). For training, I took out the side magnets and shoved the bottom magnet to the side as shown in the instructions. One cat used it immediately for treats! For a day and a half, the second cat would only use it when we held the flap open. By the end of the second DAY, they were both using it regularly! After a week, I moved the bottom magnet over so that it worked on the bottom of the flap, and after pushing the flap for them a few times, they were pros. A week and a half later, I put the side magnets in, and they didn't seem to notice any difference! There is no cold air coming in at all now! Or neighbor cats! We have NOT had any problem with the aluminum "sweating" as some reviewers did. I did apply the protective treatment that came with the door. We ordered the white, and it looks nice - much less noticeable in the window than I had thought it might be. I wish I could post a pic! Highly recommend this product!

K
05/08/2016
Krisa
Superb

Quality exceeded my expectations. Highly recommend.

R
02/15/2016
Rally
Cats are happy.

All but one cat has gotten use to the new flap. Since it was for cats, they put in only one magnet in. One side doesn't always close tight and I have to help it. I'm thinking of asking for 1 more magnet. Overall, the door is very sturdy and helps keep the cold out. I would recommend it to anyone. It is pricey, but so far, I feel it's worth it.

A
01/19/2016
ally
excellent pet door

this pet door is absolutely worth it. it is definitely worth the money. it is easy to install and my cats learned how to use it without great difficulty

Endura Flap Thermo Sash 3e Cat Doors for Sash Windows

White / 22" - 25" Edit

The Thermo Sash 3e Cat Doors for Sash Windows, which has a flexible clear flap and a long horizontal white frame.

Size Chart

Flap SizeFlap DimensionHeight to Raise Window
Small6" x 11"18 1/2"

  

Adjustment Ranges:

  • 22" - 25" Custom Order
  • 25" - 28"
  • 28" - 31"
  • 31" - 34"
  • 34" - 37"
  • 37" - 40"
  • 40" - 43"

 

Pet door has 1" framing, measure your track width to make sure that your window will accommodate the sash.

Final Sales: Adjustment Range 22" - 25" are final sale and cannot be returned. Final Sale products are made to order and will take extra time to ship.

 

Flap Material

Flexible

Your Maximum Pet Size

Cats

Installation Instructions

Installing the Thermo Sash 3e




sash window pet door diagram

PARTS

  • 1x Sash Window Pet Door
  • 1x Foam Weather Strip
  • 1x Center Post Weather Seal Draft Stopper

INSTALLATION INSTRUCTIONS

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

inserting the sash into the window track

Step 3: Apply the foam weather-stripping by peeling back the paper and exposing the adhesive. Unroll it along the edge of the sash, pressing to ensure it adheres. Install on both the top and the bottom. Trim to fit with scissors.

applying the foam weather stripping

Step 4: Mount the Center Post Weather Seal Draft Stopper. This strip prevents air from leaking between the window frame when raised to accommodate the sash. Trim to fit with scissors.

mounting center post weather seal draft stopper

LOCKING YOUR WINDOW

permanent lock option

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, shown in Detail 1.

switching the side of the flap

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.

removing a pet door flap

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.

setting flap back in

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.

adjusting window height for sash pet door

Videos

How to Measure Your Sash Window for a Pet Door





Design of the Endura Flap





Adjusting Magnet Strength for Training





Leaf Blower Test


FAQ

What do I need to know/measure before I order?

First raise up your window and check that it can go up far enough to be left with an opening 18 1/2" high. Next measure the width of the track from left to right, including going inside the track on both sides. Last measure how wide the track is that the window slides in (needs to be at least 1")

How wide does the track have to be for the Thermo Sash 3e to fit?

Track width needs to be at least 1" thick.

Can I choose what side the door is on?

It comes standard on the left, if you are looking from the inside of the house. You can switch it to the other side if you need and that only requires a screwdriver.

Is this easy to install?

This is designed to be a fairly simple install that does not require any tools. Take a look at the video under the installation tab to see if it something you would be able to do.

Will this door be good for more extreme weather?

The Thermo Sash 3e has the Endura Flap which is far better in sealing and durability than other models. Dual pane lo-e glass offers superior insulation value. Therefore, the Thermo Sash will be a much more reliable and longer lasting option then the more inexpensive options.

Is it possible to make one that fits a window smaller than 22"?

We can, the only thing is that we would not be able to use glass so there would be quite a bit of aluminum and some customers are not happy with the aesthetics. This would also fall under the custom and non-returnable category.

My cat is having a hard time opening the flap is there something I can do that would make it easier?

You can by removing some of the magnets. On the videos tab check out the "Adjusting Magnet Strength for Training."

What if I mis-measured?

If you've mismeasured, you may be able to fix it. To make your sash cat door about 1" wider, you may purchase a width extension (or make your own using 1" x lumber). To make your window kitty door insert slightly shorter you may trim the side flanges on the spring loaded adjustment piece with a hacksaw or a jigsaw with a metal cutting blade.

What does custom mean?

Any of the Thermo Sash doors with "Custom" listed means that the door is built to order and therefore it is non-returnable.

Can I get a custom height?

We can only do custom widths, not custom heights.

Warranty

Patio Pacific Inc Endura Flap Pet Door Lifetime Warranty

The Endura Flap lifetime warranty guarantees that any defective parts returned with proof of purchase will be replaced by the manufacturer for free. This excludes damage caused by accident, improper installation, overuse, or misuse—including damage by pets or glass breakage.

Customer Reviews
4.8 Based on 20 Reviews
Write a Review

Thank you for submitting a review!

Your input is very much appreciated. Share it with your friends so they can enjoy it too!

Filter Reviews:
T
12/05/2017
tay
very nice

works like a charm, measuring was a little difficult to make sure everything was ready to go. It keeps everything well insulated, love the high quality of the glass and flap. It is air tight!

P
11/16/2017
Patty
Wonderful product

My husband and I are so happy with this cat door! We have two cats that just turned a year old. We let them go outside during the daylight hours when we are home. I was constantly letting them in and out, or leaving the back storm door propped open, letting the flies and neighbor cats in as well. My husband did not want a pet door, but I convinced him to give this one a try since no holes were drilled in walls or doors. I was able to easily install the window by myself following the video instructions, adding some shims (provided) to make everything line up, and also some insulation strips (provided). For training, I took out the side magnets and shoved the bottom magnet to the side as shown in the instructions. One cat used it immediately for treats! For a day and a half, the second cat would only use it when we held the flap open. By the end of the second DAY, they were both using it regularly! After a week, I moved the bottom magnet over so that it worked on the bottom of the flap, and after pushing the flap for them a few times, they were pros. A week and a half later, I put the side magnets in, and they didn't seem to notice any difference! There is no cold air coming in at all now! Or neighbor cats! We have NOT had any problem with the aluminum "sweating" as some reviewers did. I did apply the protective treatment that came with the door. We ordered the white, and it looks nice - much less noticeable in the window than I had thought it might be. I wish I could post a pic! Highly recommend this product!

K
05/08/2016
Krisa
Superb

Quality exceeded my expectations. Highly recommend.

R
02/15/2016
Rally
Cats are happy.

All but one cat has gotten use to the new flap. Since it was for cats, they put in only one magnet in. One side doesn't always close tight and I have to help it. I'm thinking of asking for 1 more magnet. Overall, the door is very sturdy and helps keep the cold out. I would recommend it to anyone. It is pricey, but so far, I feel it's worth it.

A
01/19/2016
ally
excellent pet door

this pet door is absolutely worth it. it is definitely worth the money. it is easy to install and my cats learned how to use it without great difficulty