# Minimum cat flap hole?



## phil209 (Jul 28, 2013)

I'm planning to drill a hole in an external wall for a cat flap. Does anyone know the minimum hole size that an average cat needs?

A regular diamond drill will cut a 15cm hole. Anything bigger, needs an expensive and awkward drilling rig which is a bit much.

I'll probably go for 15cm, maybe do two overlapping holes if the drill can handle it, so that they overlap to form an oval type hole. Or maybe 15cm is fine. The wall is 25cm thick so the cats need to crawl through the hole and not just step through it like with a door capflap.

The only other place to fit a catflap in my room is in the roof, so they'd need to climb up a wall, then down the side of the extension. Or replace a £400 glass panel in my sliding doors.


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## chillminx (Nov 22, 2010)

The best place to fit a catflap is in an external wall. I certainly would not put one in a roof!

A builder fitted the cat flap to an external wall in my house. It took about an hour and a half, and cost me about £60 in labour costs. But you sound as though you are experienced in this kind of thing, so will not need a builder. However, I strongly recommend before you cut a hole in your wall you buy the specific cat flap you are intending to use, as this will give you your template.

The best type are the battery operated microchip catflaps (e.g. by Sureflap),as then no strange cats can get in your house through the flap. (I assume your cats are already microchipped, but if for some reason they are not, then it is a simple job for the vet to do).

Along with the catflap you will need to buy a tunnel, and possibly a tunnel extender -- to go through the wall. Sureflap sells these too.

Sureflap do 2 different sizes, the small size is OK for an average to small sized cat, the larger one is suitable for large cats, or cats who are long legged (like 2 of mine).

If you are using an ordinary cat flap the same thing applies. Buy the flap first to get the template, and also buy the add-on tunnel (and extender if required) at the same time. Cat Mate make a fairly good inexpensive model.

Amazon.co.uk: cat flaps for walls

Note: It is better to get all the bits to go with the cat flap, as it gives a better, neater finish, and is more comfortable for the cats to walk on as they go through it. The plastic is also very easy to clean.


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