Cat flap in metal exterior door

[Betsy]

I want to install a cat flap in my back door to allow my cat to go out on the screened in porch whenever she wants to. The door is a typical low-end flush metal mobile home door that is about 1.5" thick. I've installed these things a few times in the past but never very neatly for lack of the right tools. The opening is to be almost nine inches round and I figure I can drill starter holes but then what? Do I have to buy or rent a jigsaw which I assume is electric? My drill is a rechargeable home-use drill, not powerful like professional models, so I figure it is not strong enough to spin a big keyhole saw. I'd very much appreciate some advice if anyone has experience to share. Thank you.

[JD]

If this is your typical mobile home door, the metal skin can be scored hard with a utility knife, then use a screw driver to push on the metal on the hole side of the cut. This should just bend in a separate at the cut. From there, a pair of pliers would pull the rest of the hole metal off of the door. Inside the door, you will either find a cardboard or foam filler, easily cut with most anything. I have a little hand saw that accepts sawsall blades which is perfect. From there, I would drill holes through the corners of the cut hole to mark the location and cut that hole like the first.

Now comes the problem of a weak door hole. Some pet doors will just want to collapse the door. There is a popular brown door with brown plastic screws (I have a couple of these). There is a spacer that helps hold the two sides apart while still allowing you to tighten down the screws. But on these mobile home doors, I would go a step further and use ferrules on the screws. Something made of metal, tin or heavy aluminum, to be spacers going around each screw. You could also use 5/16" brass pipe from the hardware stores, but they could get expensive. Just something that would stop the screws from collapsing that area of the door. Cut the ferrules about 1/8" shorter than the thickness of the door to be sure to get a good seal on the pet door.

[DaveyB]

Given how flimsy those doors are, and how hard it would be to repair it if anything goes wrong (read: replace the whole door), have you considered going through the wall of the home next to the door? Nobody said that a cat or dog door has to be installed in a door, and a wall, especially a wooden wall, is a lot more forgiving in the case of mistakes !

Just an idea!

DaveyB

[Betsy]

JD and DaveyB - I am so grateful to both of you for your input. I never would have thought about the pet door compromising the sturdiness of the door itself. Everything make sense to me about preventing the screws of the pet door from squeezing the flimsy metal skins of the house door. We get hurricanes here and I did wonder about how well a plastic pet door would hold up to high winds trying to enter the house. I'm thinking now that I better just leave things alone and let my cat in and out the old fashioned way. I had built for her an elevated screened and chicken wired "fort" that she could access from a bathroom window. The pet door was installed in a piece of plastic placed tightly in the small bathroom window. But I've had to take the fort down because the wood it was made of is rotting away. That's why I had the idea to put the pet door in a place where she could go on the porch. If I had a way to install the pet door rin the wall I would but there is a clothes dryer in the way. That's another issue - the clothes dryer vent pipe hole is in the floor and that causes my dryer to have to sit a LOT farther into the room than it would if it vented out the wall instead. I asked someone about making a vent pipe hole in the wall and he told me that there's no way since we can't tell if there is any electrical wiring in the wall at that location. So the same issue would apply to a hole for a pet door too I guess.