This is how high up the cat door needs to be from the bottom of the hollow core door.
Cat door height from floor.
Measure the height of your cat s belly from the ground to its stomach with a measuring tape.
Choose a warm day.
Measure your cat s belly to the floor.
7 1 8 7 1 2 width height 3 easy steps to select right size cat door 1 2 3 1.
Add one to two inches.
Width measure the widest part of your cat the chest or hips.
Petsafe cat door size chart pet door size pet weight flap opening size width height small 1 15 lbs.
2 for clearance for dog s back not to hit dog door 24 height of desired dog door opening.
Now you know how high the door must be to accommodate your tall dog.
If you need to install the cat door higher consider placing steps either side to help your cat to get in and out more easily.
This will give you the best dog door size for your household.
Cut out the square hole with a jigsaw and smooth the edges of the hole with fine grit sandpaper then place the cat.
Measure the height and width of the cat flap and mark the dimensions on the door using the height of the cat s stomach as the center point.
Subtract the height of the dog door opening for instance 16 24 16 8 height off the interior floor for the dog door install opening.
You will need to take the measurements of your largest and smaller pet.
You need a pet door that has a flap height that is at least 1 taller than your largest pet and a step over no more than 1 3rd of your smallest pet s height from the floor to their back.