Installing a cat flap into your door 

UK Home Improvement

Installing a Cat Flap into Your Door 

Installing a cat flap often makes your life easier. A cat flap is a super helpful opening that allows your cat, or even dog, the freedom to come and go as they like. They help your cat feel more in control of how it comes and goes, not to mention that you won’t be jumping up every 10 seconds to let it in or out. If it’s cold outside, your pet can get in easily, which takes that worry off your mind.

Mostly though, doors aren’t built with your pet’s access needs in mind.

First Things to Consider

There are many botched cat flaps out there. And your door or window could become seriously weakened if the job isn’t done well. And don’t overlook that security. Not only is an improperly installed cat flap can be a security risk but a cat flap does offer the chance for people to reach in and hook keys that have been left within arm’s reach. So, get it properly installed and keep car and house keys out of sight.

Installing a Cat Flap into Glass

If you want to install a cat flap into a glass pane, it’s not impossible but it’s best to get a new pane with the hole already cut.

Door glass is usually toughened and so by its nature, very difficult to cut through. Just the very act of taking a drill to it increases the chances of it shattering. Cutting toughened glass also makes it susceptible to cracking later on, increasing the security risks.

If you’re considering cutting a cat flap installation into glass, definitely employ the services of a glazier. You’ll need a circular hole, rather than a square too, as circles offer less risk of the glass cracking, because there are no corners where the integrity of the glass is at it’s weakest.

Many cat flap suppliers have adapters that will accommodate the flap into a circular hole.

If you are in a rental property, it’s better to remove the pane completely and have a new one, with the cat flap installed, fitted. If the pane is removed, you can replace it later if you move on.

It’s not the cheapest option but will save your deposit if you’re renting. But as mentioned, it’s not a bad idea taking this approach, even if you’re not thinking about replacing the pane at a later date.

These days there are even options for sliding patio doors, with slimline solutions that won’t stick out and block your doors from opening or shutting.

Cat Flap Height

You might have seen those cat flaps that are too high. The cat has to perform a gymnast’s routine to get in and out of the flap…

But the flap’s height is actually really important. If it’s too high, your cat won’t use it and you’ll be left with a hole in a perfectly good door for nothing. It’s easy to prevent.

Before the cut is made, check to see if your cat needs to take a running jump to get through it. If it does, measure again. Don’t guess, or you could be creating an expensive hole.

Fitting Cat Flaps into UPVC Doors

Fitting a flap into a solid UPVC door panel is generally much easier than fitting one into glass. UPVC doors have a solid panel in the bottom half of the door and most cat flaps will come with a template for cutting the right size hole into the door. You just need to be comfortable with using the cutting tools required for the job.

In the case of these doors you measure, cut and secure the flap into place. Again, however, it’s best to install the flap from the outset, rather than cut later. But if you do have an existing UPVC door and now require a cat flap, it’s much easier than trying to install one into a glass door.

Final Thoughts

You’ll find cat flaps everywhere, these days, even in solid walls.

So it’s not a problem, but always plan it out first. Think about the type of flap, the placement, the height from inside and outside. Think about the type of material your door is made from.

Often it’s better to install it when the door is being built, but this isn’t always possible.  And when you’re thinking about cutting a hole in such an integral part of your home, it’s always best to get professional help if you have any doubts.


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