Rim (wheel) Rim (wheel) The rim is the "outer edge of a wheel, holding the tire". It makes up the outer circular design of the wheel on which the inside edge of the tire is mounted on vehicles such as automobiles. For example, on a bicycle wheel the rim is a large hoop attached to the outer ends of the spokes of the wheel that holds the tire and tube. In cross-section, the rim is deep in the center and shallow at the outer edges, thus forming a "U" shape that supports for the bead of the tire casing. In the 1st
Rim joist Rim joist In the framing of a deck or floor system, a rim joist is attached perpendicular to the joists, and provides lateral support for the ends of the joists while capping off the end of the floor or deck system. Rim joists are not to be confused with end joists, which are the first and last joists at the ends of a row of joists that make up a floor or deck frame. A rim joist's relationship to the joists is similar to what the top or bottom wall plate is to the studs. It is also confusingly called