Joist dimensions are only part of the equation.
Building an attic.
In many cases ceiling joists for dead loads are designed to carry 10 pounds per square foot.
An attic may also be called a sky parlor or a garret because attics fill the space between the ceiling of the top floor of a building and the slanted roof they are known for being awkwardly shaped spaces with exposed rafters and difficult to reach corners.
Adding a floor to an attic can increase storage space or create a new room.
An attic sometimes referred to as a loft is a space found directly below the pitched roof of a house or other building.
Building code also requires that the prospective attic living space be accessible by a full size staircase with at least 6 foot 8 inch clearance above it.
Other structural issues are also factors including whether there is adequate space to install a stairway to the attic.
You also need to ensure that the joist spacing is adequate.
Make sure the attic has a full size staircase.
To meet most building codes your attic should.
When converting an attic to a living space it must meet the same building requirements as the other rooms in your home.
Attics only accessible by trapdoor style staircases or ladders aren t technically finishable.
Have at least 7 feet of vertical clearance in the majority of the room be a minimum of 7 feet wide and have at least 70 square feet of space available.
Building code often requires stairway access to the attic if the space is to.