What size PlexiDor do I need?

Having the right size dog door or cat door will make it even more enjoyable for your pet. Many think pet doors look small, and our eyes trick us into thinking the pet needs a much larger door than is necessary. We humans are used to doors that are much bigger than we are, but pets don’t need that much space to go through. On the other hand, they shouldn’t have to crawl to get through the door. The solution is: measure.

The opening width should be a little wider than the widest part of your cat or dog. If you have more than one pet – measure the largest one.

To find the opening height, measure your pet from the top of the shoulders to the chest – just behind the front legs. The door doesn’t have to be as tall as the pet is – they will duck their head and lift their legs when going through – but they shouldn’t have to squeeze through. We recommend installing the pet door with a two inch clearance from the top of a dog’s back.

A tip for measuring dogs is, call the dog to you and mark the height with your finger on your own leg. It’s easier to measure yourself than the dog.

Once you have these measurements, look at our size chart to see which door will be the best fit. You can test the door size through cutting a hole in a piece of cardboard and testing if your pet can go through.

If a small and a large pet will share the door

Make sure the door is installed high enough for the tallest pet to pass through without hitting their back – remember the two inch clearance – but still low enough for the small pet to get over the threshold. Measure your smallest pet from the ground to its belly – the bottom of the opening shouldn’t be higher up than this.

You may have to go up a size and get a bigger door to accommodate all the pets. The panels on a PlexiDor swing so easily that a smaller pet can open a larger door.

In some cases you can also put a step up to the opening of the door, to help the smaller pet.


If your pet is older, or has joint issues

Pets age just as we do, and deserve to have the best in their golden years. Some are prone to back problems, others may get arthritis. This means they may not be as keen on ducking down to get through a pet door as when they were younger. Some get problems lifting their legs high, or are reluctant to jump.

In these cases, it’s a good idea to go up a size and get a larger door. This way, you can mount it closer to the floor and give the pet a lower threshold while still keeping the top high enough to avoid having to crouch, or hitting their back.

There is usually a drop-down on the outside of a house. The older dog may need a ramp or steps, so they don’t have to jump.

Dogs with long backs, like Dachshunds, can have a hard time with wall-mounted doors. They can’t reach to step over the threshold and the tunnel. In these cases, a ramp or steps may  be a great solution.

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