Q: I'm looking around for a new apartment in the city, and I see all the new loft-style places for rent have bare concrete floors. Concrete is so cold. Why do they do that?
A: The irony of loft-style apartments is that the industrial look isn't exactly inexpensive! It is, however, durable, which is desirable for a rental. To have a concrete floor look good enough to stand on its own as a finished floor requires a few extra steps and attention to detail than concrete that would be covered with something else. (All that exposed ductwork comes at a price, too. The kind that is usually buried behind a wall isn't very attractive.)
I agree with you: Natural gray concrete floors look cold and feel cold, too, to your bare feet. This happens with any hard flooring, including stone or tile, and to a lesser extent, even wood floors. Still, although the warmest looks for hard flooring is wood, stone or tile floors, concrete can also be stained a beautiful color. But to give, literally, a warmer feel to your feet, you can use area rugs especially next to the bed and other furniture. (If somebody is planning a new floor, they can add heating elements to the floor, too.)
Part of what makes these loft apartments seem cold is the echoing sound, so soft materials would absorb noise for a quieter environment. Adding furniture, art on the walls, books, and area rugs help.
And carpet works well because it covers so much area.
Yet, especially in a rental situation, carpet can trap allergens and dirt. In extreme conditions without good ventilation, moisture can cause mildew and mold growth. New carpeting may off-gas, and most any carpet can stain. Pets can cause all sorts of problems, too. Cleaned regularly, the right carpet can be a great addition to a space to add warmth and a cozy feel.
For landlords, though, the easy maintenance of a concrete floor over carpeting — or even wood — is probably an easy choice, which is why you see a lot of it in modern, loft-style apartments.
Go with your gut feelings as far as your location preferences and budget, and know you can warm up concrete floors and express your style with your own area rugs. Good luck.