When finishing an attic (or basement, for that matter), headroom is a key factor. While building codes vary from place to place, the “rule of sevens” is important here: Most regulations will require the finished space to be at least 70 square feet, 7 feet wide, and have 7 feet of head clearance for at least 50 percent of the space. (Still, check with a contractor or a building inspector to make sure you’re following all the local regulations.) And remember: That seven feet is after the ceilings and wallboard are added, so it’s important to factor that into your measurements, lest you come up short.
There are other safety factors to consider, too, such as the weight capacity of the floors and the ability to safely run electrical lines. An electrician and structural engineer should be consulted before you decide to go through with your renovation in case your floors or walls need to be upgraded to support wiring and furniture.