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21 Construction and Demolition

Debris

We have to discard the past and, as one builds
floor by floor, window by window,
and the building rises, so do we go throwing down
first, broken tiles, then pompous doors,
until out of the past dust rises as if to crash against the floor,
smoke rises as if to catch fire
and each new day it gleams like an empty plate

Pablo Neruda (1904–1973)
Past

21.1 INTRODUCTION

Construction and demolition (C&D) debris is generated when new structures are built and existing
structures are renovated or demolished (Figure 21.1). Structures include residential and nonresi-
dential buildings and public works projects such as streets, highways, bridges, and piers.
Components of C&D debris include concrete, asphalt, wood, metals, gypsum wallboard, and roof-
ing. State definitions of C&D debris may also be expanded to include trees, stumps, soil, and rock
from clearing construction sites.

21.2 CHARACTERISTICS OF C&D DEBRIS

Sources of C&D debris include homebuilders, homeowners, commercial developers, building con-
tractors, highway and street contractors, bridge constructors, bituminous pavement contractors, home
remodelers, site grading contractors, demolition contractors, roofing contractors, drywallers, and
excavating companies (Franklin Associates, 1998). The major activities that generate C&D debris
from buildings include the construction, demolition, and renovation of residential and nonresidential
buildings (Figure 21.2). Residential buildings include single-family houses, duplexes and high-rise
multifamily housing. Nonresidential buildings include commercial, institutional, and industrial build-
ings. Approximately 123 million metric tons (136 million tons) of building-related C&D debris were
generated in the United States in 1996 (Table 21.1). Forty-three percent of the waste (58 million tons
per year) was generated from residential sources and 57% (78 million tons per year) from nonresi-
dential sources. Building demolitions account for 48% of the total C&D waste stream, renovations
account for 44%, and construction activities generated the remaining 8% (Franklin Associates, 1998).
Construction activities generally produce cleaner materials than does demolition. Demolitions
generate wastes having several materials bound together or contaminated with hazardous materials
such as asbestos or lead paint. Renovation projects can produce both construction and demolition
type wastes. The sources of C&D debris are listed in Table 21.2.
The composition of C&D debris is highly variable and is a function of the specific activities tak-
ing place at the site. For example, concrete is the largest component of building demolition debris
and wood is the largest waste component generated at construction and renovation sites. Typical
components of C&D debris are listed in Table 21.3.

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