A field-fabricated enclosure around an air-handling system, usually built on a waterproof concrete base which has a curb around it with floor drains, or built on a floor which is sloped toward drainpipe openings.
A field-fabricated enclosure around an air-handling system, usually built on a waterproof concrete base which has a curb around it with floor drains, or built on a floor which is sloped toward drainpipe openings.