Do I need storage?

How do you keep steel buildings cool inside? They're a breeze to build (I'd think like those 'recyclable' buildings) and all, but what about temperature control ah?

Especially in Malaysia where the weather is hot and occasionally stormy. I read that it'll depend on several factors, but I couldn't be bothered with the details now.

But now I can't think of I would need a metal shed of sorts.