A guide to installing a cat flap for your feline friends

Let your cat wander with their new flap!

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You've probably wondered how your cat can be restless when you're not home. Why not give yourself peace of mind by learning how to install a cat door in your home?

Cat doors or cat flaps are small-sized doors that allow your feline friends to go in and out of your house to potty or roam as they need. So, if you want to know things like how to install a cat flap in a door or how to install a cat flap in a wall, check out this guide.

What do I need to install a cat flap?

Before you start installing your cat door, prepare the following tools and materials:

  • Cat door kit

  • Measuring tape

  • Pencil

  • Paper

  • Ruler

  • Scissors

  • Drill with a 1-inch bit

  • Saw

  • 1-by-2 wood plank

  • Wood glue

  • 4 C-clamps

  • Phillips screwdriver

  • Saw horses

Cat flap installation tips and completion time 

Determine which part of the house to install the cat flap. Keep in mind that placing it in interior doors with a hollow core will require added preparation and work, as a wooden support frame will need to be installed in the interior of the door.

When choosing a cat door, consider the price, the size of your cat, and if you have multiple cats sharing the door. For example, if you have one cat bigger than the other, it's best to go with a flap that fits the larger cat. 

You must also consider where you'll set it up, as this will determine the material of the cat flap you'll use. Depending on the area, the cat door must be able to withstand extreme weather, rain, or snow.

Installing a cat flap can be as quick as less than an hour or more, depending on the type of door material you intend to place the cat door on.

Step-by-step guide to cat door installation

Step 1: Prepare the door

a man unscrewing the door hinges of a white door

Before starting the project, unscrew the door where you'll install the flap from its hinges and lay it on a table or saw horses (if you have these around). This is to help you cut and place the cat door precisely where you need it and allow you to work on this project comfortably at standing height.

Step 2: Get measuring

a worker measuring the cat door placement

Using a measuring tape, measure the height of the cat's belly from the ground to its stomach. This is how high the cat flap needs to be from the bottom of the door.

Measure the flap to find its centre point. Start by marking 12 inches up from the floor at the centre point on the interior and exterior sides of the door.

Then, cut out the cat flap template included in the kit by transferring its dimensions and cutting it out. Place the template in the centre with the bottom lined up to the 12-inch centre point mark you created earlier. Trace around the template, ensuring the marks are as even and level as possible.

Step 3: Mark it with holes and start sawing

drilling a hole in a door for cat door

Using a drill with a 1-inch bit, drill a 1-inch hole on each corner of the door pattern to create access points for the saw. Carefully follow and cut along the traced line of the pattern with the saw.

Make sure to wear proper safety gear when handling power tools. Always be careful when using such tools. 

Step 4: Create the wooden frame

close up shot a tabby cat in a cat flap

Measure the interior dimensions (width, height, and length) of the cat door hole. These measurements will be used to make a wooden support frame for the cat door opening. 

Cut out four pieces of wood from the 1-by-2-inch wood plank. Cut a piece per each side of the opening from the dimensions you gathered.

Step 5: Fit the pieces in

cat crawling through a newly installed cat flap

To attach the wooden frame, follow these steps:

  • Apply wood glue to the sides of the cut wood pieces and insert them onto the wooden door. The top surface of the wood pieces should line up with the cut edge of the cat door opening. 

  • Use C-clamps to hold each section of the door to a wood piece, and wait at least 12 hours for the wood glue to dry.

  • Once the glue has set, you can install the cat door's interior side.

  • Loosely attach the interior side to the wooden door by screwing the centre screws on each side of the door.

  • Install the exterior frame into the hole of the door. 

  • Push the frame into the door until the flanges of each side meet on the inside. 

  • Loosely attach the frame of the cat flap with screws.

  • Test it to ensure that the cat flap is aligned with the door and fits well.

Step 6: Secure the door in place

cats testing out their new cat flap

Once you're happy with the positioning and your cat can comfortably go in and out of it, you can start securing the pieces with the screws. Reattach the door back to its door frame by screwing back the hinges. Then, wait and see your feline friends test their new door! 

In case this project isn't something you're confident to do yourself, you can call a handyman to help you with tasks like this. You can also reach out to them if you need to repair broken cat flaps. 

Surprise your feline companion with a cat flap! 

Allow your feline friends the freedom to move in and out of your house to roam, exercise, or potty by installing a cat flap!

Whether you have no time to install the cat flap yourself or prefer it done by pros, we got you! You can find reliable Taskers to help you place handy flaps around your home for your cats. 

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Frequently asked questions

Yes, you can! You can install a cat flap into a uPVC door easily since you can simply cut a hole in the door. Remember to follow our guide to ensure that the fit of the cat flap is appropriate for your cat.

Installing a cat flap is a relatively easy DIY project; chances are you already have the required tools to do it. The installation will vary, depending on the material of the flap and the style.

If you prefer a less traditional cat flap, you may opt for a microchip-powered cat flap, where a microchip placed in a cat’s collar lets the cat in and out once the cat flap senses it. You may also use a window to allow your cat to go in and out. However, this will still require some altering to ensure that only the cat can access your home and not unwanted intruders. 

Yes, you can! You can install an interior cat door by following our step-by-step guide. It covers the basics of cat door installation, from sizing your feline friends down to placing the frame. 

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