Best Sliding Glass Door With Pet Door Built-In: Reviews and Buyer’s Guide

Although pet doors come with obvious advantages — the freedom to allow your pet to head out as he pleases — it also comes with a minor disadvantage: it forces you to make a huge permanent hole in your door, wall, or window to install the flap in its place.

If you own a sliding glass door, however, cutting a hole won’t be a concern. 

A sliding glass door with pet door built in often doesn’t come pre-installed. Luckily there are manufacturers that make pet door panels specifically to fit the frame of your sliding door, without having to damage anything in the process. 

In this article, we’ve compiled a list of the best pet doors available for sliding doors, including a complete buyer’s guide and how to install your door panel yourself. 

Note: If you click some of the links in this article we may earn a small commission at no additional cost to you.

Top 5 Best Sliding Glass Pet Doors of 2020: No Cutting Needed

Like all pet products, there are hundreds of sliding glass pet doors available to purchase. Below are some of the most noteworthy doors you should definitely check out.  

Endura Flap Pet Door Thermo Panel – Best Overall 

If you’re looking for a highly insulated pet door, look no further than The Endura Flap Thermo Panel 3e. 

Engineered with two layers of Low-E glass and a polyolefin polymer flap that magnetically seals, this pet door offers supreme insulation and combats even the harshest climates. It blocks harsh UV rays to avoid affecting your home’s interior temperatures. 

This removable panel doesn’t require any tools or overly complex installation. This is possible because it has a spring-loaded design that allows you to safely insert and secure the panel in place. 

Its magnetic seal is adjustable, too, which is handy for when your pet is struggling to push through the flap. Simply dial back the resistance down and you’re golden. This makes it perfect for preventing dirt and debris from getting inside your home on windy days. 

Because it’s surrounded by heavy-duty metal, the Thermo Panel 3e is considered to be one of the most robust panels out there. 

Moreover, it includes a sturdy slide-in locking cover to keep unwanted critters out. This will also be convenient if you want to keep your pet safe and sound inside your house.

Endura Flap provides flap sizes that range from small to extra-large to accommodate all pets. To fit the interior design of your home, Endura Flap also offers multiple frame color options like dark bronze, white, or brushed aluminum.

Endura Flap Pet Door Thermo Panel 3e - Large Flap (10" x 19"), Height Range (77.25" - 80.25") White Aluminum Frame
  • ✔ FLAP SIZES… Multiple flap sizes: Small 6"w x 11"h; Medium 8"w x 15"h; Large 10"w x 19"h; and XL 12"w x 23"h. Small and Medium panels ship with a 3" stepover (adjustable to 5"). The Large and XL panels ship with a 5" stepover (adjustable down to 3" or up to 7"). Maximum pet height by flap size: Small 15"; Medium 19"; Large 23"; and XL 29". Includes locking cover as strong as 1/16 inch sheet of steel to control pet's exit or entrance and secure your home.
  • ✔ SLIDER WIDTHS & HEIGHTS... All require a track at least 1" thick (thicker tracks may need shimming). The opening for people to use will be reduced by the following widths: Small flap panels 10 3/16"; Medium flap panels 12 1/4"; Large flap panels are 14 1/4"; and XL flap panels 16 5/16". Height ranges determined by measuring from lowest point of lower track to highest point in upper track. If your panel is a little to tall to fit in slider opening, you can trim up to 3/4" off the top flange.
  • ✔ STRONG ALUMINIUM FRAME AND LoE GLASS… Dual layer magnetically sealed pet-safe flap, energy efficient LoE glass, and surrounded by heavy duty metal to be long-lasting and robust.
  • ✔ AWARD-WINNING ENERGY EFFICIENCY… Our patio panel pet doors keep out the winter cold or the summer heat even in the harshest climates, and keeps those energy bills down
  • ✔ IDEAL FOR RENTERS & VACATION HOMES … If you don’t want a permanent pet door, the Endura Flap Thermo Panel satisfies both needs; install or remove as desired


  • Tool-free installation
  • Made with eco-friendly materials 
  • Has a structurally sound design that’s built to last 
  • Spring-loaded design allows for easy removal if need be


  • A bit expensive 

PetSafe Freedom Aluminum Patio Panel Sliding Glass Pet Door – Easiest to Install

The PetSafe Freedom Panel Sliding Pet Door is a sturdy, attractive sliding door insert. It has a heavy-duty aluminum construction and features a wide range of height adjustments, flap sizes, and three frame colors to choose from. 

Installation is a breeze with this pet door, and it can be easily detached in case you need to remove it when traveling or moving to another house. 

It also comes with shatter-resistant glass, which is a welcome bonus. This will ensure that you won’t need to constantly replace parts of your pet door, making it a sound investment for years to come. 

A locking cover, pin lock, and weatherstrip are included in the box for extra safety. This will additionally allow you to securely control your pet’s access to the outdoors when it’s time to come inside and cozy up. 

PetSafe 1-Piece Sliding Glass Pet Door for Dogs & Cats - Adjustable Height 75 7/8" to 80 11/16" X-Large, White, No-Cut Install, Aluminum Patio Panel Insert, Great for Renters or Seasonal Installation
  • PERFECT FOR APARTMENTS AND RENTAL HOMES: This rental-friendly door installs easily in 1 piece so you can easily take it with you if you and your best friend move
  • 2 ADJUSTABLE SIZES: The patio panel is available in 2 adjustable heights to fit in your existing sliding door track; adjustable up to 80 11/16 in or 96 in
  • DESIGNED FOR EXTRA LARGE PETS: Flap opening is 13 11/16 in W X 23 3/4 in H for pets up to 220 lb
  • SECURITY LOCK: The latch kit allows you to lock your sliding glass door once the pet door is in place
  • CONTROLLED ACCESS: Use the closing panel to limit your cat or dog’s access when needed


  • Made with an aluminum frame with tempered glass, making it highly durable 
  • Includes security panel
  • Quick, DIY installation 
  • Comes in white, bronze, and brushed aluminum frame color options


  • Glass isn’t double-paned, so it doesn’t work well for extremely cold weather 

Ideal Pet Products Fast-Fit Aluminum Pet Patio Door – Best Aluminum Sliding Pet Door

The Ideal Pet Products Fast Fit is specifically designed to fit aluminum sliding patio doors. 

This cost-effective panel installs without the requirement of tools due to its lightweight, single pane glass, and spring-loaded design. With a name that says “fast-fit”, we expect no less! It’s easy to put up and take down, making it a great choice for renters. 

The clear vinyl flap isn’t heavy, allowing both dogs and cats to go in and out with ease. 

It comes with a sturdy aluminum frame and can be adjusted to measure between 77’5/8” and 80’3/8″. With its 5 different sizes of flaps, Ideal Pet allows you to choose the right size for your pet. 

When not in use, Ideal Pet also installed a magnet under the flap to keep it closed. 

Perhaps one of the best features of this pet door is that it includes a 4-way security lock system for added protection. This means that you can adjust it to exit-only, enter-only, in-out privileges, or fully locked. 

Ideal Pet Products Aluminum Pet Patio Door, Adjustable Height 77-5/8" To 80-3/8", 6-1/4" x 6-1/4" Cat Flap, White
  • Designed for ALUMINUM Sliding Patio Doors Only and is NOT INTERCHANGEABLE.
  • The Ideal Choice for Rentals. Install and Remove Easily, No Tools Required.
  • Adjustable Height: 77-5/8" To 80-3/8" (80") To ensure ordering correct height, measure flush at top track to the inside bottom track of your ALUMINUM Sliding Patio Door frame.
  • Features a 6-1/4" x 6-1/4" solid, clear lockable plastic flap.
  • Available in two finishes: White or Satin Silver (Mill) to match your patio door.


  • Its sleek design will complement the interior design of your house
  • See-through flap that’s lightweight for pets 
  • Comes at a great price 
  • Durable aluminum frame 
  • Easy and quick installation lives up to the “fast-fit” name 


  • Door might be too thin for some sliding doors 

Ideal Pet Products VIP Vinyl Insulated Pet Patio Door – Best Insulated

The VIP Vinyl Pet Patio Door is a perfect option for those with vinyl patio doors. Its vinyl frame allows for a higher insulation value than conventional metal frames because it uses tempered glass. 

Made with unbreakable LEXAN clear plastic, a draft stopping seal, and three rigid panels, this chew-proof pet door is solid, secure, and long-lasting. 

If you’d like to replace the flap with something see-through, an ABS plastic locking cover is included at no extra cost. 

Ideal Pet Products 78" VIP Vinyl Insulated Pet Patio Door, Medium, 6.38" x 11.25" Flap Size
  • Designed for VINYL Sliding Patio Doors Only and is NOT INTERCHANGEABLE
  • Height Adjusts From 76-3/4" To 78-1/2”. To ensure ordering correct height, measure flush at top track to the inside bottom track of your VINYL Sliding Patio Door frame
  • White VINYL frame features Energy Efficient DUAL PANE tempered “Low-E” glass
  • Medium size 6-5/8” x 11-1/4" flexible 3-part Double Wall LEXAN flap pet door with animal lock-out slide; Includes everything needed for installation
  • Need Assistance? E-mail Ideal Pet Products expert US-based customer care specialists seven days a week! Manufacturer Warranty does not apply to product purchased through Amazon Warehouse Deals or any used product sellers


  • Designed for harsh, four-season climates. 
  • Unmatched energy-efficiency 
  • Fits vinyl sliders perfectly without gaps
  • Made to match vinyl doors as if they were built together 


  • Isn’t the easiest to install 
  • Only works for double-pane sliding glass doors

PetSafe Sliding Glass Cat and Dog Door Insert – Best Budget

Available in three sizes, the PetSafe Sliding Glass Door Insert is built to last. It’s made with extremely sturdy aluminum and long-lasting tempered glass. It also comes with two latch kits so you can securely lock the door when need be. 

The slide-in closing panel adds another level of security when your pet isn’t around to use the door. Like the PetSafe Freedom Aluminum Patio Panel, this one also comes with a weatherstrip for better house insulation. 

Nothing about this panel will inherently cause interference with your security system, so you don’t have to rewire or reinstall your safety alarm. PetSafe made this door to match with your existing sliding glass door, so it looks quite attractive when installed. 

PetSafe Sliding Glass Cat and Dog Door Insert - Great for Rentals and Apartments - Small, Medium, Large Pets - No Cutting DIY Installation
  • PERFECT FOR RENTALS AND APARTMENTS: This rental-friendly door is easy to install and detach using removeable adhesive strips so you can easily take it with you when you and your furry friend move
  • EASY INSTALLATION IN 2 PIECES: Automatically adjusts to fit into your existing sliding door tracks with no cutting; easily installs in most left or right sided sliding glass door frames up to 80 11/16 in tall
  • ADDED LOCKING SECURITY: The latch kit enables your sliding glass door to lock, and the slide-in closing panel adds another level of security when your pet isn’t using the door. Caution: Small children can pass through door
  • ENERGY EFFICIENT: The door has weather stripping and a tinted flap with magnetic closure to keep the heat and cold outside
  • STRONG AND DURABLE: Built to withstand heavy use, the door has an aluminum frame and tempered glass; 1 year warranty


  • PetSafe provides extra hardware to allow different installations
  • Great deal for your money
  • Sturdy and leaves no permanent marks to the door or frame
  • Detachable panel automatically adjusts to fit into your existing sliding door tracks


  • Not as easy to install as advertised 

Best Brands for Sliding Glass Pet Doors 

There are a ton of companies that sell pet doors, but only a few are truly the best. Between the brands we’ve considered, these three companies stand out the most.

Endura Flap 

The roots of Endura Flap go all the way back to 1976, but it wasn’t until 2004 that the company created their first-ever pet panel for sliding glass doors

Endura Flap is a company that makes high-quality, flexible, and safe pet doors of all kinds. This includes pet doors for walls, doors, and windows. 

All their products are made to keep your home insulated with environment-friendly polyolefin flaps and sturdy aluminum frames. They’re built to last for a long time, and they even offer lifetime warranties for normal wears and tears. 


If you’ve ever owned a pet, you’ve most likely heard of the PetSafe. 

PetSafe makes a variety of pet products, including collars, filters, litter trays, batteries, and, of course, pet doors. It’s now considered to be the largest manufacturer of electric pet training products in the US and has sold its products across 52 countries. 

Overall, Petsafe is a great company with great products, and customer service second to none. 

Ideal Pet 

Ideal Pet is a company that creates state-of-the-art electronic dog trainers, pet doors, and affordable accessories. Their pet doors are one of the most easy-to-assemble, versatile and aesthetic models on the market. 

5 Things to Consider When Buying a Sliding Glass Pet Door

Pet doors are the perfect option for two things: for when you want your pets to go potty outside without your assistance, or when you’re simply too tired to constantly open your door to let your pet in and out of the house.  

With sliding glass pet doors, you won’t have to cut a hole in your front or back door to install a flap. But don’t buy until you know the ins and outs of the panel you’re looking to purchase! 

Here are some things to consider before buying a sliding glass door with a pet door built-in. 

One Size Does Not Fit All  

Size is essential. You’ll need to find a pet door that actually fits your pet. If your door is too small, your pet won’t be able to comfortably get in and out of your house. 

When buying a pet door, you’ll have to find a flap that’s 2 inches bigger than your pet’s shoulder height. This is important just in case your pet gains weight as they age. 

Moreover, you’ll need to make sure that the door you’re getting actually fits your doorway’s tracks, and whether your existing sliding door can accommodate the size of an additional panel. 

You also wouldn’t want to install a sliding pet door that limits your own doorway space, so make sure you have enough space in your desired location.

Get your measurements ready before spending big bucks on a pet door.  

Durability and Stability

A quality sliding glass door insert is one that lasts for a long time and doesn’t wear easily. 

If you have a pet that tends to bite and chew his toys, there is a possibility that he’ll do the same to the pet door. Some doors are made of bite-proof material such as aluminum or vinyl.

It’s also better to purchase a panel that is easy to install and remove. This is useful for when you need to take a vacation to avoid worrying about your pet escaping.

So to reiterate: 

  • Search for a door that has vertical supports to solidify its overall strength. 
  • Make sure it has a thumb lock that can hold the panel in place for more stability. 
  • Avoid pet doors made of wood or plastic panels as much as possible.

Safety and Security 

When buying a pet door, make sure that it can be easily locked. This will ensure that your pet stays inside the house when you need them to, and prevents strays or other animals from getting into your house. 

If you have a particularly big dog door, the locking mechanism will make sure you won’t have to worry about burglars crawling through your flap. The same applies to your young children. 

Some security-friendly pet doors won’t open unless it scans your pet’s microchip when they’re approaching the pet door. Some can be locked with the press of a remote. 

Tinted flaps are an option, as well. This will prevent burglars from peeping into your home to check if someone is inside. 

Energy Efficiency

Do you live in an area that gets super cold or hot? If that’s the case, you may want to purchase an energy-efficient pet door. 

Most of these doors have multiple flaps that allow them to protect your home from the outside temperature. Plus, they often come with weather-tight seals. This is handy for when it’s particularly windy outside or when it’s raining.

The common terms that are often used to describe energy-efficient pet doors are as follows: 

  • Draft-prevention
  • Draft control
  • Insulated 
  • Weather-resistant 
  • Weatherproofed 


Compared to standard pet doors installed in wooden doors, sliding pet doors can be double, or even triple the price. Paying a professional to install the door can cost another $100 to the total price tag. 

The good news is that pet door panels that fit in sliding doors are quite simple to install. You don’t have to cut anything; you’ll only need to fit it into the tracks of the door. 

By the nature of the beast, the pet door will be pricier if you have a large pet. Nonetheless, you’ll have to make sure that your pet fits comfortably inside the flap as it may seriously hurt your pet when you opt for a “cheaper”, smaller door. 

If you’re a bit tight on budget, you’ll perhaps need to stay away from extra features that you’re not sure you’ll ever use. 

Frequently Asked Questions

Looking to know more about sliding glass pet doors? We’ve got you covered.

Q: How do I install a pet door in a sliding door?

Sliding pet doors are perfect for when you don’t want to cut a permanent hole on your door. The beauty of these types of pet doors is that they can be easily fitted into your existing sliding door with just a few simple modifications. 

Here’s a step-by-step guide on how to install a pet door into your sliding door. 

Step 1: Taking Measurements 

There are two things you’ll need to measure: your pet, and your sliding door. 

Measuring Your Pet 

One of the most important things to do before purchasing a pet door is to make sure you’re buying one with the right size. You don’t want a door that’s too small or too big for your pet. 

To measure your pet, follow these steps: 

  1. Measure the widest part of your pet’s body.
  2. Once done, add about 2″ to your girth calculation. 
  3. Then measure how tall your pet is from his shoulder to his feet. 
  4. Add about 1″ to your length calculation. 

And you’re done! It’s that simple. These measurements will ensure that your flap is wide enough to let your pet comfortably jump in and out of the door. 

Measuring the Height of Your Sliding Door 

After measuring your pet, it’s time to measure your door. Decide where you want to install your pet door and make sure it matches your slider. This is important because once you’ve installed the additional panel for your pet flap, the remaining area of your sliding door will decrease. 

Measuring Your Track Width or Thickness

This step is often overlooked, but it’s just as important as the two mentioned above. Measuring your track’s width beforehand will allow you to determine if the panel you’re looking to purchase will fit on your track’s slot. You don’t want it to sit too loose or to not fit at all. 

Measure your door’s track width, from your home’s interior to its exterior.

Once you’ve jotted all the measurements down, you’ll be ready to buy the pet door. 

Step 2: Inserting the Panel in Your Track 

Soon after you have ordered the panel, you’ll first need to loosen the thumbscrews that come with the product. 

Doing so will release the spring mechanism that’s found in almost all sliding pet doors. The resultant pressure will expand the door until it fits in the height of the track. 

Place the panel into the top of your door’s track first before doing the same on the bottom track. Make sure you slide the whole thing against the door jamb resting on the side of your wall. 

Step 3: Finalizing Installation 

Once you’ve inserted your pet door into the track, you can now install any other extras that may come with the panel. This includes weather staps, glass sweep, and locks.

You’ll, of course, need to tighten the thumbscrews to make sure it’s fully secured and safe for your pet to go in and out of. Don’t forget to lock the height adjuster, as well. 

And you’re done! If you’ve followed these steps, you’ll be able to install the pet door without the aid of a professional. Many kinds of panels typically follow the same procedure for installations. You should typically find some minor differences in the user’s manual. 

Q: Will I have to replace flaps and parts every year?

It depends on the quality and brand of your pet door. Higher-quality pet doors may not require replacement parts for a long time, while less expensive doors might need replacements every year or so. 

This is why it’s advisable to invest in a more expensive pet door as it’s more cost-effective in the long run. 

Some brands, like Endura Flap, offer lifetime warranties for normal wears and tears. Always check your pet door’s warranty before buying to make sure you’ll be getting the support you need just in case your pet door gets damaged prematurely.

Q. Will the panel interfere with my alarm system?

Possibly. Some pet doors may cause your alarm system to go off, especially if it interferes with its wiring. To avoid this, you’ll have to check with your alarm company and heed their advice. 

Final Thoughts 

For those who want to avoid permanent alterations to their sliders, sliding glass pet doors is the answer. It’s the perfect choice for rentals and vacation houses, and for those who want to keep the view and beauty of their home.

Remember, before buying a sliding pet door, make sure you have the exact measurements down. Many buyers get disappointed with their purchase because the panel is either too big or too small. We wouldn’t want that to happen to anyone else! 

If you want a sliding glass door with pet door built in, all the products we’ve listed above are solid choices. If we had to choose the best overall, our pick would be the Endura Flap Pet Door Thermo Panel. 

It has everything you need in a pet door: great insulation, built with durable material, and can be easily installed. Its lifetime warranty to wear and tear is a valuable additional bonus!