On my lot I have a garage which I use for various types of storage. At the moment the floor is paved with concrete bricks, and the walls are made of concrete fence. Suffice to say it's not the prettiest and I am trying to come up with ways to make it a little bit comfier.
The main challenge is that it's unheated, will never be heated and I live in Poland where over the year the temperatures go from -15°C to 30°C (5°F to 86°F).
What types of materials could I use to make even and clean floor and walls? I don't particularly mind if overtime they'll get a little crooked, have cracks or whatnots.
For floors I was thinking about floor panels, not solid wood but fiberwood (don't know how those are called in English, the ones that are made of dense fiberwood meant to imitate real wood panels but thinner). Unfortunately I've read a lot of conflicting opinions about those so I am not confident it'd work well, plus it also raises the question what to put underneath them, to keep them even and avoid moisture from the ground destroying them, if that even is an issue.
For the walls I was thinking plasterboard, finished with wall putty and painted over, probably with paint that allows moisture to pass through.
But those ideas come from very uneducated place.