Fitting a Cat Flap

· 6 min read
Fitting a Cat Flap

Installing a cat flap in your home is a great step for any pet owner. There are many options available for you, no matter if your cat is getting older and needs extra security or you have kittens that require to be examined.

It can be a bit daunting for non-professionals to install an animal flap, but with the right instructions it's easy. Planning, preparation and precision are the keys.

Choose the Right Door or Window

There's a wide selection of cat flaps to choose from including some with locks (which can be used to prevent your pet from leaving or entering) and others with high-tech features like microchip door entry systems. However, it's important to think about how easy it is for your cat to train to use the flap before you buy and install one.

It is best to place the cat flap, based on the design of your home, inside the form of a window that opens to a garden that is sheltered. This will allow your cat to feel secure when entering or leaving your home. If  window with cat flap  will also provide them a route back in should they get chased by another cat or by humans intent to hurt them.

It's possible to install a cat-flap in a uPVC or composite door, but it's not as easy as putting one on a wooden door. It's because uPVC or composite doors come in various thicknesses. This could affect the way holes are cut, and the material you put into.

To avoid costly errors to avoid costly mistakes, it is recommended to consult a professional glazier prior to installing the flap on a door with a glass front. If you're installing the flap to the door made of wood you must introduce your cat to it first so that it can become familiar with its dimensions and shape.

Measure Your Cat's Belly

You'll need the measurements of your cat to ensure that the cat flap you install is a perfect fit. This will help you make sure that the flap is placed at the right height on the door or window, and that it is large enough for him to enter and leave easily.

To do this, put your pet on their back and gently run your fingers along their belly. Look for any fat pads that are squishy that might be visible around their lower back, face and limbs. The extra padding protects your pet and allows it to move more freely, especially when performing feline Acrobatics.

Alternatively, you can also consider your pet's weight as a way to gauge how big an opening you need. If your cat weighs at or over 5kg, for example that's a 14x12cm flap for the cat is advised.

Take a measurement of your door or window

This kind of cat flap, as its name suggests, is designed to be installed into a door. It lets your pet move in and out at their convenience. They are usually made of plastic or aluminium and simply rest in the middle of the door. They come with the possibility of a swinging door that is opened by pushing lightly on either side. The flaps are available with locking options which provide extra security so that your cat is not able to traverse the door from outside.

A window is another common location for a cat's flap and these are easy enough to put in, but they are usually located high enough as it's difficult for dogs and cats to access them. If the window is too high for a cat flap, ramps, steps or specially constructed stairs can be used to help the animal access it.

A cat flap can be installed into a brick wall but this is not recommended unless you are skilled in masonry work as it could weaken the structure of the wall. It's important to check that there aren't any cables or pipes within the wall before you start. You should always consult a professional if you need to cut a hole in the wall for cables and pipes. It's also advisable to wear goggles with a protective lens and a dust-proof mask to prevent inhaling any sawdust that is created by cutting through the walls of your house.

Choose the Cat Flap that is right for you.

There are a variety of cat flaps available on the market, and they come with different features. Certain cat flaps come with security features such as magnetic locks or microchip recognition that prevent unauthorized entry. They also stop your pet from letting friends or animals to enter the home. Certain seals are weatherproof and have insulation to block out moisture and draughts.

There are also different sizes to choose from based on the breed and size of your pet. Cat flaps can be found in rectangular shapes, whereas others are square or circular. The kind of cat flap you choose will depend on the dimensions of the opening as well as the type of window or door you're fixing it to.

Also, think about the mechanism for opening your cat flap will come with. A simple plastic or aluminium swing-out door is a good option and is usually the cheapest. However, it won't stop other pets or cats from entering and you may let draughts through as well.

It's time to put in your cat flap. Start by marking the belly's height on the door with a ruler. Make use of a spirit-level to ensure that the line isn't too low and is in line with the door. Create a template for the shape of the cat flap using your spirit level as a reference. Then, use a jigsaw to cut out the outline of the door. Once you're happy with the results sand down the edges and then drill through the pencil marks to create holes for the screws.

Prepare the Tools

Like all DIY jobs, it's always recommended to have the right tools to complete the task. You'll require the cat flap as well as tape measure and pencil, a spirit-level, a drill and a jigsaw depending on the type of window or door.

Check with the manufacturer prior to making any changes to a door made of composite. This could invalidate the warranty or cause the weathertight seal to be broken. In this case it's likely you'll have to replace the glass with a fresh piece of toughened glass.



You'll need to use the jigsaw to cut your cat flap on a wooden or uPVC door. Follow the instructions given by the manufacturer. Make use of a template to determine the size of hole you require.

After you've cut the required hole, you'll need to smooth the edges of the opening to smooth them. This will stop the possibility of water damage and rust. Finally, you should apply any sealant that is needed to the rear of the cat flap, and to the holes in the window or door to block the elements of wind and rain. Once the sealant is dry, you're ready to install your new cat flap!

Install the Flap

If you want your cat to be able to come and go as it pleases, fitting flaps can be helpful. This is a simple process that most people can complete themselves, although you'll likely require the help of an expert for installing the flap in an unglazed door or any other type of uPVC door.

Take a look at the instructions that came with your cat flap. There is an illustration of the template. This will give an idea of where holes need to be drilled for the flap in the door. Then, mark the places that you'll must drill using pencil.

After you have marked the area on your door, use the jigsaw to cut the design for the cat flap. This is a relatively easy job, but you'll require a good understanding of the jigsaw. If you are worried about doing it yourself, there are many companies that can do this for you at a very low cost.

Then, attach the outer part to the hole of your door. It is possible to seal it prior to making this move to ensure it remains weather-proof and water resistant. You can then place the outer portion of the flap on the top of the fixing bolts, and tighten the bolts all together. You should test the flap on your cat to make sure that it functions properly and that it allows them to enter and exit easily.