Many bedrooms spaces are used for other activities in addition to sleeping. Minimum bedroom dimensions should to take into account the local building codes as well as all the furniture needed for these activities and storage spaces for clothing and other items. All the furniture in a bedroom must be easily accessible, with enough space between the pieces for a person to move safely.
In its 2006 International Residential Code, the International Code Council states that each habitable space in a house should be a minimum of 70 square feet, with each wall being at least 7 feet long. Many states base their building codes on this document. For example, the California building code does not define what a bedroom is, but states these minimum dimensions for "sleeping spaces."
Although many bedrooms are multifunctional spaces, their main purpose is for sleeping, and the central piece of furniture is the bed. The size of bed determines the minimum bedroom dimensions. The standard size for twin, or single, beds is 39 inches wide by 75 inches long and double beds are generally 54-by-75 inches. Queen beds are longer at 60-by-80 inches as are king beds 76-by-80 inches. Bedrooms should include space to access the bed on one or more sides. For example, you could position a bed against walls at its head and on one side, and leave access to it on the other long side.
Even a bedroom used primarily for sleeping may need to include other furniture. End tables hold reading lamps and bedtime accessories such as water glasses, books and tissues. Clothes are usually stored in either a built-in closet or stand-alone wardrobe, while the drawers in a dresser hold folded clothing items as well as socks and underwear. Hanging clothes on hooks on the wall also needs unused wall space and floor space to access them. Multifunctional bedrooms may need to accommodate desks for homework, shelves or bookcases for books and other items and perhaps a chair for guests.
By carefully planning the layout of a bedroom of minimal dimensions, you can extend the usable space. Bunk beds provide two sleeping spaces in the floor area of one. Loft beds are raised beds on a platform, and free the space underneath for additional play space or furniture such as a desk or dresser. Using containers that fit under the bed efficiently increases the storage capacity of the bedroom, while floor-to-ceiling shelving units with adjustable shelves provide ample storage space for many differently sized items, while occupying a minimal floor space area.