A native of Worcester, Massachusetts, he gained an international reputation for large-scale works of art held in museums, public, corporate, and private collections, which are executed in media as diverse as light, kiln-formed glass, metal, stone, mosaic, and ceramic.

[5] During this early stage in his career, Knapp worked closely with Polaroid Corporation on their 20x24 camera, creating large scale instant photographs.

Various types of ceramic, mosaic, metal, stone, and glass filled his studio as he developed the innovations for which he is known today—combining mediums and processing techniques and working craftsmen, fabricators, and manufacturers from around the world on an increasingly grand scale.

The following year he used photo-transfer techniques to define the images to be etched and anodized in aluminum, creating one of the world's largest etched-metal murals—a 14-foot × 72-foot piece for the Hamilton County Justice Complex in Cincinnati.

During the 1990s, his increasing fascination with light led Knapp to kiln-formed glass—the heating of glass to take on the shape of a form below, resulting over the decade in large installations across the United States.

In a series of solo shows in 2004 and 2005 Knapp experimented with new coatings and laminating techniques that took him beyond dichroics and increased the range of his palette and gave him greater control in painting with light.

2009 saw a commissioned installations and a solo lightpainting exhibit at the Chrysler Museum of Art, Norfolk, Virginia, Throughout Knapp's career there have been constants: a continuous research into materials; a commitment to the techniques and processes involved in enlarging his design; an exploration of the historical, cultural and technical precedents that formed the bases for both his personal and commissioned pieces; and, above all, light.