built-up
1. having many buildings (esp in the phrase built-up area)
2. denoting a beam, girder, or stanchion constructed of sections welded, riveted, or bolted together, etc.
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
Built-up
A structural member made up of two or more parts fastened together so they act as a single unit.
Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved
built-up
1. Assembled by fastening a number of parts together.
2. Fabricated of several layers, thicknesses, or pieces which are laminated or fastened together. built-up air casing 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.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.