With a mezzanine level (an internal balcony overlooking the space below), you can add a room more easily and - usually - for less money than converting your loft or cellar or building an extension.
A mezzanine can have all sorts of uses - a dressing room, home office, studio, spare room, bed platform or play area in a child’s room (bed platforms are also popular in high-ceiling studio apartments). However, there are lots of practical considerations. To start with, if you want to stand up comfortably in both the mezzanine and the space underneath it, the room should have a ceiling height of at least 4.2m (13ft 9in), unless it’s a small child’s room.
Whatever you use the mezzanine for, you’ll also need something to enclose it. A balustrade or half-height wall are popular choices because you still get a feeling of space, although you do, of course, lose some privacy. You’ll also need a staircase up to the mezzanine. Ladder-style ones are fine for kids, but not ideal for adults, and remember spiral staircases save space. For another clever use of space, tuck things under a (conventional) staircase, such as a built-in home office or storage, or even a wet room or kitchenette.
One thing you don’t want to do without is adequate soundproofing, because this could affect your enjoyment of the mezzanine and the room below. Don’t forget the importance of natural light either.