Pet Doors - Choosing the Right Size
Measuring Your Dog for a Pet Door One of the easiest ways to tell a bogus dog door web site is by the recommendations they make regarding the size of dog a particular pet door is suited for.
"Dogs to 150 lbs" or, even worse, "large-sized" dogs are a terrible disservice to the consumer who is apt to think he or she is dealing with a knowledgeable company.
To make matters worse, everyone including me and even you, dear reader, over-estimates the size pet door they really need.
It's an optical illusion that's very common.
So if you get "up-sold" on size--and, therefore, price--you may never realize it.
At the same time, it's even worse to buy one that's too small as I'll explain below.
And you're not going to realize that the pet door is too small for a very long time either.
Your young, vigorous, teen-aged dog can get through just about anything for a while.
So what do we do? Well, let's start by asking what our goal is.
Sure, it's to let the dog in and out when he wants without having to be a 'door opening slave' (this catchy phrase was invented by a pet door manufacturer named Pet-Eze in the 1970's).
But, if you think about it, what you really want is to not be opening the door for your dog for as long as possible.
Let's put it this way: Your dog has a lifespan of, say, x years.
The closer to 'x' that he's able to use his door, the better because when the time comes that he can't use it successfully, well, then, you've got a big problem.
Your life, in a real sense, revolves around the fact that Fido can get in or out when he needs or wants to.
What changes do you have to make once he can't? They might be really big ones.
Just one example: For years you ran home at noon to let the dog out to 'do his business'.
Then you got a dog door and could quit making that trip.
Then you got a job 30 minutes further away.
Then the dog quit using the dog door because he couldn't manage it.
Now what? Ok.
Down to business.
In a nutshell, we want to make the pet door as 'accessible' as possible for the dog you own.
Not some hypothetical 100 lb dog but your particular dog.
What does 'accessible' mean in this context? It means that you've chosen a pet door that is as easy for your dog to use as possible without being any larger than needed.
First, measure his height at the highest point of his body when he ducks his head to go through.
Usually, this is the 'withers' (the top of the shoulders) but sometimes it can be the hind end.
If the top of the flap opening is at least that high, then he won't have to crouch going through.
Crouching can be very difficult for a dog with arthritis, bad hips, an injury or just plain old age.
Next, crack open a bedroom door just wide enough for him to come and go comfortably.
This is easiest with two people and some treats for motivation.
Whatever you do, don't use your tape measure directly on the dog! You just can't measure accurately that way.
Not even close.
The height measurement was pretty objective but the width is more subjective.
Three different people will come to three different conclusions about how much width is 'enough'.
I've talked with customers that want 'plenty of room' and others that say 'let him squeeze a little'.
Neither is wrong (though if the dog is in the habit of charging through after a squirrel, I worry about him bruising a shoulder on the way!).
Now comes the part most often forgotten: The 'step-over'.
My company invented the term 'rise' about 25 years ago and now everyone uses it.
But the meaning of 'rise' isn't very obvious to most people and we're now using 'step-over' on our new website.
When it comes to step-over, less is always better but not always easy to achieve.
For example, you have to keep some dimension beneath a pet door going through a door or you compromise the strength of the door.
That dimension is going to vary depending upon the door construction, so get some professional advice if unsure.
Likewise, when installing a pet door through a wall, you can't cut through the mud sill.
So the lowest you can get in a wall-mount pet door is 1 1/2" for the mud sill plus however much the framing of the pet door happens to be.
Have a care, though, if you've got high molding and don't want to cut down into it.
Your 5" molding could turn into an 8" step-over and that might be more than your dog can handle when he's my age.
Ok, so now we've got the information we need to make some sense of the website you've been looking at.
We've got a width which can be a little wider but not any more narrow.
We've got a height of the opening which can be a little higher but no lower.
And, we've planned for a step-over that is as low as we can get it.
Here's a concrete example.
Since my company manufactures dog doors, I'll use one of them as an example.
General stands 20" at the withers so I know I need to get the opening up to at least 20".
He easily fits through a 7" width.
The Endura Flap #06 is only 6" wide so I need to go up to the #08 which is 8".
The #08 is 15" tall so if I position the top of the opening at 20", the bottom of the opening will be at 5".
Since the framing at the bottom is 1 1/2", I'll have 3 1/2" at the bottom of my solid wood door.
I think that's enough but wouldn't want much less.
Now I'm ready for the salesman who suggests the #10.
I don't need it! Though if you hold a 10" x 19" pet door next to General, it would appear to be about right.
Notice that the Endura Flap #08 opening measures 8" x 15".
It's what we call a 'high-aspect-ratio' pet door.
By comparison, the Pet-Eze company that I mentioned above offered an 8" by 11" size.
With that door, General would be stepping over 9"! Or else he'd be crouching if I mounted it lower.
Either way, he'd use it for years but not for as long as he would the 8" x 15".
If I wanted the 15" in height that I need from Pet-Eze, I'd have to get the 10" x 15" size and now I've got a dog door that's more expensive and now large enough for a person to crawl through.
Bad choice! A final note.
This analysis is only a good starting point.
There are other considerations that might serve to modify your selection.
For example, say my dog is 5 years old and in great shape and I plan to sell the house in 2 years.
I don't need the most accessible possible because he's not going to grow old with this particular pet door.
Or I've got a big dog that I'm measuring for but also a small guy that I want to use it as well.
Or maybe I just can't afford the one I'd really like to get.
At least when you deviate from the optimal you know what you're doing and you're not being swayed by a salesman that really doesn't know what he's talking about.
"Dogs to 150 lbs" or, even worse, "large-sized" dogs are a terrible disservice to the consumer who is apt to think he or she is dealing with a knowledgeable company.
To make matters worse, everyone including me and even you, dear reader, over-estimates the size pet door they really need.
It's an optical illusion that's very common.
So if you get "up-sold" on size--and, therefore, price--you may never realize it.
At the same time, it's even worse to buy one that's too small as I'll explain below.
And you're not going to realize that the pet door is too small for a very long time either.
Your young, vigorous, teen-aged dog can get through just about anything for a while.
So what do we do? Well, let's start by asking what our goal is.
Sure, it's to let the dog in and out when he wants without having to be a 'door opening slave' (this catchy phrase was invented by a pet door manufacturer named Pet-Eze in the 1970's).
But, if you think about it, what you really want is to not be opening the door for your dog for as long as possible.
Let's put it this way: Your dog has a lifespan of, say, x years.
The closer to 'x' that he's able to use his door, the better because when the time comes that he can't use it successfully, well, then, you've got a big problem.
Your life, in a real sense, revolves around the fact that Fido can get in or out when he needs or wants to.
What changes do you have to make once he can't? They might be really big ones.
Just one example: For years you ran home at noon to let the dog out to 'do his business'.
Then you got a dog door and could quit making that trip.
Then you got a job 30 minutes further away.
Then the dog quit using the dog door because he couldn't manage it.
Now what? Ok.
Down to business.
In a nutshell, we want to make the pet door as 'accessible' as possible for the dog you own.
Not some hypothetical 100 lb dog but your particular dog.
What does 'accessible' mean in this context? It means that you've chosen a pet door that is as easy for your dog to use as possible without being any larger than needed.
First, measure his height at the highest point of his body when he ducks his head to go through.
Usually, this is the 'withers' (the top of the shoulders) but sometimes it can be the hind end.
If the top of the flap opening is at least that high, then he won't have to crouch going through.
Crouching can be very difficult for a dog with arthritis, bad hips, an injury or just plain old age.
Next, crack open a bedroom door just wide enough for him to come and go comfortably.
This is easiest with two people and some treats for motivation.
Whatever you do, don't use your tape measure directly on the dog! You just can't measure accurately that way.
Not even close.
The height measurement was pretty objective but the width is more subjective.
Three different people will come to three different conclusions about how much width is 'enough'.
I've talked with customers that want 'plenty of room' and others that say 'let him squeeze a little'.
Neither is wrong (though if the dog is in the habit of charging through after a squirrel, I worry about him bruising a shoulder on the way!).
Now comes the part most often forgotten: The 'step-over'.
My company invented the term 'rise' about 25 years ago and now everyone uses it.
But the meaning of 'rise' isn't very obvious to most people and we're now using 'step-over' on our new website.
When it comes to step-over, less is always better but not always easy to achieve.
For example, you have to keep some dimension beneath a pet door going through a door or you compromise the strength of the door.
That dimension is going to vary depending upon the door construction, so get some professional advice if unsure.
Likewise, when installing a pet door through a wall, you can't cut through the mud sill.
So the lowest you can get in a wall-mount pet door is 1 1/2" for the mud sill plus however much the framing of the pet door happens to be.
Have a care, though, if you've got high molding and don't want to cut down into it.
Your 5" molding could turn into an 8" step-over and that might be more than your dog can handle when he's my age.
Ok, so now we've got the information we need to make some sense of the website you've been looking at.
We've got a width which can be a little wider but not any more narrow.
We've got a height of the opening which can be a little higher but no lower.
And, we've planned for a step-over that is as low as we can get it.
Here's a concrete example.
Since my company manufactures dog doors, I'll use one of them as an example.
General stands 20" at the withers so I know I need to get the opening up to at least 20".
He easily fits through a 7" width.
The Endura Flap #06 is only 6" wide so I need to go up to the #08 which is 8".
The #08 is 15" tall so if I position the top of the opening at 20", the bottom of the opening will be at 5".
Since the framing at the bottom is 1 1/2", I'll have 3 1/2" at the bottom of my solid wood door.
I think that's enough but wouldn't want much less.
Now I'm ready for the salesman who suggests the #10.
I don't need it! Though if you hold a 10" x 19" pet door next to General, it would appear to be about right.
Notice that the Endura Flap #08 opening measures 8" x 15".
It's what we call a 'high-aspect-ratio' pet door.
By comparison, the Pet-Eze company that I mentioned above offered an 8" by 11" size.
With that door, General would be stepping over 9"! Or else he'd be crouching if I mounted it lower.
Either way, he'd use it for years but not for as long as he would the 8" x 15".
If I wanted the 15" in height that I need from Pet-Eze, I'd have to get the 10" x 15" size and now I've got a dog door that's more expensive and now large enough for a person to crawl through.
Bad choice! A final note.
This analysis is only a good starting point.
There are other considerations that might serve to modify your selection.
For example, say my dog is 5 years old and in great shape and I plan to sell the house in 2 years.
I don't need the most accessible possible because he's not going to grow old with this particular pet door.
Or I've got a big dog that I'm measuring for but also a small guy that I want to use it as well.
Or maybe I just can't afford the one I'd really like to get.
At least when you deviate from the optimal you know what you're doing and you're not being swayed by a salesman that really doesn't know what he's talking about.
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