A system for suspending an acoustical ceiling in which no suspension members are visible in the room.

Routing at the bottom of a cabinet door or drawer to provide a means of opening and closing without pulls.

Piping which usually requires the removal of permanent construction to gain access to it.

A gutter built into the eaves of a roof, usually metal-lined.

A grid support system that is not visible from below; used in certain types of suspended acoustical tile ceilings.