How to build an affordable catio?

emcdiy

Hi everyone!

I am wanting to build a catio outside for my 2 cats (4-6kg), however it is likely to be relatively temporary, 2-3 years maybe, as I don't own my house so I am not wanting to spend a fortune and don't really know where to start with building materials!

I will attach a photo of the space I am working with and an inspo pic to give you a rough idea of what I'm planning to do, however I am hoping to make the catio a bit longer ~4x1.2m and about 1.8-2m tall.

I was planning to do this with 90x45mm timber, but this will be far too expensive unfortunately. Is there a cheaper alternative that will still provide enough support for my cats? Would also appreciate a suggestion for what screws to use for this, as well as what I could use to create some perches/shelves for them to climb and rest on.

I will also need to build a tunnel that leads to the cat flap which will rest on the ground. What size wood and screws will be best for this?

Some other random questions:

Is it necessary to seal/paint the wood or can I leave as is? If it is necessary, is it best to do this before or after assembling?

Is it necessary to fix the structure to the wall or is there a more temporary solution?

Is it possible to do this project in a cost effective but safe way? Or is it best to come up with an alternative plan?

Thank you so much in advance for all your help!!

MitchellMc

Welcome to the Bunnings Workshop community @emcdiy. It's wonderful to have you join us and many thanks for your question on building a catio.

It sounds like a lot of your questions are being driven by keeping costs down, which makes total sense given this is a temporary structure. Before getting too far into materials, do you have a rough budget in mind? We can absolutely help put together a materials list, but if it ends up well over what you’re hoping to spend, it’s not all that helpful, so having a target budget will let us guide the choices a bit better.

In terms of framing, it’s definitely not necessary to use 90 x 45mm. Something like 70 x 35mm H3 treated pine is a more cost-effective option and will still be suitable for the main structure. For bracing, fixing your mesh, and building the tunnel, you can step down further to 42 x 18mm treated pine, which helps keep costs down while still doing the job.

For fixings, 75mm treated pine screws will work well for the main frame, and you can drop down to 50mm screws for lighter sections like the tunnel. That’ll make assembly easier and avoid splitting thinner timber.

All of this timber is suitable for outdoor use, but painting or sealing it will definitely help it last longer, especially if you’re aiming for a couple of years. A good budget-friendly option to look at is something like British Paints 4 Seasons Low Sheen White Exterior Paint, which is designed for exterior conditions and offers protection against sun, rain and mould while still being relatively affordable. For a project like this, even starting with a small tin and applying a single coat will make a noticeable difference. It’s usually easiest to assemble the structure first, then paint it before attaching your mesh.

For stability, since you’re after something temporary, you don’t necessarily have to fix it to the wall. You could make it freestanding with some extra bracing or weight at the base. That said, if it’s tall and narrow, a couple of light fixings into the wall (that can be patched later) will make it much safer overall.

Overall, it’s absolutely possible to build something that’s both cost-effective and safe. You just need to be a bit strategic about where you use heavier timber versus lighter sections.

You might like to check out some of the previous catio projects our members have shared, such as our most popular projects: Indoor to outdoor cat tower by @Shannon and Cat enclosure by @Chrissie35.  

Please let me know if you have any questions.

Mitchell