Cat House Using Cardboard. Seal the bottom of the box with duct tape. You can build your own from corrugated cardboard poster board or any other lightweight material but an existing box will be much sturdier.

This cat owner went all out. How to make an indoor cardboard cat house. Make a bunch of them to house the feral cats that stop by looking for a warm corner in freezing weather.
You can add some toys such as some felt mice filled with catnip feather toys or just a few pieces of paper crumpled up into balls they can bat around.
This is a very simple build with only 10 steps to follow. So why spend extra money buying cat houses and trinkets to entertain your cat when you can build your own cat house with old boxes from your basement. Combine your love for crocheting cats and sharks with this DIY cat house project which is. Here is the DIY.