DIY Custom Fit Cat Run




About: Trying my hand at everything...

Cat runs are the perfect way to let your cat enjoy the freedom of the outside world while keeping them safe from the dangers (cars, dogs, feral cats, etc.) and also keeping the outdoors safe from your cat (protecting wild birds, etc.).

Our cat run was born out of nessasity and sadness as a family member's cat was recently hit by a car and passed away. Living on a main road it became very apparent that if we didn't take action the same thing could very easily happen to our cat.

With this simple home improvement we can protect our cat and give her a long and happy life.

We where fortunate for our set up that the house is close enough to the fence on two sides of the property that we didn't need to enclose much area to allow the cat all the room that she needs.

Materials for the project:
Cat Netting -
Black Rope - Also
Cat Flap
Wall Plugs & Eyelets
Timber (cheap lengths and weighty sleepers)
Zip Ties
Chicken Wire
Staple Gun Ammo
Flat Head Screws

The cat netting should be UV stabilised so it doesn't deteriorate in the sun, and bite/scratch proof. It needs to be strong enough that your cat can't break it and have a fine enough mesh that your cat can't get out through it.
We found netting to be cheaper and less work than using chicken wire for the whole enclosure (less work because galvanised mesh needs to be properly washed before use for animal enclosures).

You might have different needs and availabilities depending on where you live and what shops are available to you.

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Step 1: Prepare the Net

To prepare your net for rigging you should decide which pieces are going where, and where you want your access from. For our cat run we needed access from both ends as the house gets very close to the fence and we couldn't squeeze past it if something happened to the cat at the end without an entrance. You will also need to figure out how big you want your entrances to be. It should be big enough that you can get through (encase something happens and your cat gets hurt) and possibly even big enough to get cat toys and plants through, depending on your needs.

Sewing the sip in place is a time consuming and potentially painful process. Be careful not to stab yourself with the needle, and not to get tangled in the net.

Once the zip is in place its a good idea to run a rope along the edge. This gives the edge more strength, and makes it easier to attach to your house. Weaving it through each square of netting is best as it gives a even support for the net. Again, this process is time consuming, and can be frustrating, but take the time to do it right, and not tangle the net up and it will give a better result.

Step 2: Anchor Points

Once you have decided where you want your cat run to go the best place to start is with the end points of the netting.

We used some weighty, weather treated sleepers to hold the net to the ground.
Measure twice, cut once, discover that you cut it a little too big and cut again. The sleepers don;t need to be a tight fit, just tight enough that your cat won't be able to get past.

Depending on how tight a fit your sleeper is, and the drainage requirements at your house you should consider cutting some slots/wedges out of the bottom face of your sleeper. At our house the water needs to drain through the sleeper to keep away from the walls, and being in a tropical climate, when it rains, it rains hard, and nobody wants flooding.

Step 3: Secure to the Wall

The simplest and most secure way we found to attach the netting to the wall was via vertical pine pieces screwed directly into the wall.

Pre drill your screw holes and use wall plugs to ensure a good grip into the bricks. Then simply drill through the pine and into the wall plugs to attach.

You should consider the environment inside the cat net as to how high you will need this level of secure attachment. In this photo we went all the way to the top of the netting because of the window ledge. We didn't want our cat to climb up there and find a way to squeeze past the net.

Wait till all of your securing points are in place (all the timbers and eyelets) before starting to attach the net. I will come to this in a later step.

Step 4: Top of the Net

Decide on the height of the top of your cat run, and drill several holes in the wall. I chose to drill holes about every 5 bricks becasue it was enough to keep a good tension in the net to stop the cat from being able to climb out (if she got adventorus), but few enough that it wasn't going to take all day.

Put a wall plug in each hole and screw in an eyelet.

If you discover that you need more tension or there are gaps between the net and wall you can easily put more eyelets in later on.

Step 5: Attaching the Net - Zipper

Start attaching the net from a corner. Using an opening is a good idea as it allows you to get the tension in the net right. You want to to be firm enough that it doesn't sag much, but not so tight as to put too much strain on the staples and timber/hooks holding it to the house.

Starting from the corner staple through the side of the zipper to hold it to the pine. Use lots of staples here as there will be more tension on the zipper area when opening and closing than generally on any other area of the net. Staples are cheap, use lots.

Continue working away from the corner around your net, stapling the net to the timber where possible.

We used one sip to do the entire opening, however if/when we build another cat run we will use 2 zips.
The problem with one zip is that the tension on the cat net in the corner (pictured here) makes it hard to open and close the net. The radius of the curve is only a few centimetres, and it is very hard on the fingers to hold the net and pull the zip hard enough to get it to close.

In future we would use 2 zips which meet at this point, and open away from the corner. By using zips which have teeth on the zipper head to hold in position you shouldn't need to worry about it coming open. However if this was a concern you could put another hook eyelet under the zipper and tie it shut with some left over rope to add more security to the opening.

Step 6: Attaching the Net - Zip Ties to Eyelets

Continuing to work in the same direction away from your opening, use zip ties to fasten the net and rope firmly to the eyelets you put in the brickwork. You want to keep it as firm as you can to minimise areas where your cat might get out or other wildlife might get in (and get stuck).

Make sure the zip ties go around the rope edging (for strength) and around net squares to stop the net from sliding around on the rope.

Step 7: The Cat Flap

If you don't have a door or your windows (like ours) have security screens on them installing a cat flap is the best way to allow your cat access to the cat run.

We bought a small cat flap (for a small cat) with a lock so we can keep her inside at night, but allow access during the day (or lock her out if she is getting in the way).

Installing the flap was a simple matter of marking out the size for the opening (and plastic insert around the opening) and taking to it with my Dremel using a cutting wheel.
The security screen put up a good fight, but after a while did come out.

Be careful! the pieces of aluminium which you are removing will stay hot for a while after being cut. Removing them with pliers (or gloves) is a must, but remember where you put them as leaning on them by accident a minute or two later can still burn!

The screws included with the cat flap where designed to be put in a wooden door, not an aluminium window frame. to over come this I predrilled holes in the aluminium frame and cut some small wooden blocks to sit inside it for the screws to grip.

The cat flap is only secured on 3 corners, but that is more than enough to stop it from moving.

The fly screen was cut and folded open to still provide bug protection in the house.

Our cat doesn't quite understand that she can push the flap open. This is not a big problem, and has proven to be adventitious on several occasions (when we forgot to lock it closed). We have taped a piece of string to the flap and bulldog clip it on to the curtain to keep it open when we don't mind if she is inside or out.

Step 8: Rigging the Net - Staple to the Fence

Your cat net should nearly be up by now. The last side should be a simple matter of using the staple gun to attach to the fence.

Much like attaching to the timber on the house you want to keep the net firm. If you have any excess you can use that to make it extra cat proof by running it down inside the cat run and adding another row of staples. Work your way along from the entrance towards the back of your enclosure.

The net should be able to be worked around any obstacles along the way, such as the frame work of your fence.

Step 9: Gap Checking

Your net is up and looking great, but don't let the cat out yet! There might be places where escape is possible.

We found the the back fence didn't quite reach to the ground properly the whole way, and our cat being a tunneller would have found a way out. Using some leftover timber, chicken wire and the staple gun close off any potential escape routes.

Step 10: Release the Beast!

Once you are sure that your enclosure is as cat proof as possible it's time to release your cat!

Watch as your cat explores and plays in her new natural habitat... or just finds a place to sleep in the sun...

Every few weeks or months, or after any storms it's a good idea to inspect the cat run to make sure it's still in good condition.

If there are any plants growing (in ours weeds mostly) be sure to trim them back before they get entangles with the net. The weeds could add more weight to the net and result in pulling it down. A few minutes work every now and then will stop that.

We have only had a couple of minor issues with ours, after a very violent storm. Some of the net had pulled away from the pine frame on the house. Some new staples fixed it, and it has now been over a year since we built it, and it is as good as the day it was made.

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    11 Discussions


    Reply 6 years ago on Introduction

    Many years ago my family invested in an avery for our birds (a galagh, budgies, finches and quails). When we bought it we where strongly advised to clean it before putting it together because any trace chemicals from the galvanising process could kill our animals is they lick it (and being an avery, the birds climb the sides by holding on alternately with their beak and feet (depending on the size of the bird)).

    We where told to clean it with a vinegar and water solution to make it animal safe (make up a bucket full, wipe it on and off again, then spray with a hose and let dry).

    I don't really know anything about the processes involved, but it sounded good advice to me, and the metal did visible change from the cleaning, it became blue-er and shiny-er. Weather or not it is really required I don't know, but its a simple things to do and if it will stop your pet from getting sick and or dyeing it's worth doing!


    Reply 6 years ago on Introduction

    I often clean with vinegar knowing it is safe for the pets, thank you very much for pointing this out. Since even clothes should be washed before we wear them perhaps everything should get a vinegar rinse! I did read to rinse the pet water bowels out with vinegar and water regularly. Thanks again!

    Our car doesn't even realise she is trapped when she is in there. Occasionally she will go to the edge and try to walk through the net, but very rarely, for the most part she is happy enough that she is outside and why would she want to go further when she has a bed in the sun?


    7 years ago on Introduction

    Its better then to keep cats locked indoors, but still i would think twice before changing freedom for safety.
    I think that life is life, its not meant to be an aquarium.
    Anyway, nicely done!

    1 reply

    Reply 7 years ago on Introduction

    This is a good compromise. Our car often doesn't realise she isn't outside properly when she is in the cat run. She thinks she can go where she likes, it's just that her favourite places to sleep are in the cat run.

    Really it is as safe for her as being inside, as long as we check that it is in good condition every now and then,

    tech dawg

    7 years ago on Introduction

    this is a great job well done even though i dont have a cat its still cool


    Reply 7 years ago on Introduction

    Looks good! I thought of using chicken wire fist, but to get enough for the area we wanted to cover was going to be very expensive. The netting we found ended up being much cheaper.