CRD Waste Composition
As much as one third of the solid waste stream is construction, renovation and demolition (CRD) waste. CRD waste encompasses both residential and commercial construction, renovations and demolitions. Although residential construction generates considerable waste (building a typical 2,000 sq ft house generates 3,600 kg of waste), the majority of residential CRD waste is generated during renovations. Nearly all the demolitions are commercial buildings.
The components of CRD waste include:
Wood (34%)—In construction, wood waste sources include framing, damaged concrete forms, pallets and packing crates, as well as site excavation of trees and brush. During renovation and demolition, wood waste comes from the removal of wooden structural components. If careful deconstruction techniques are followed, significant amounts of reusable wood can be salvaged. Suitably sized wood can be re-milled into smaller wood products if its surface is too blemished for immediate resale. Wood scraps can be processed into chips for landscape mulch, fuel, compost amendment, livestock bedding, and road stabilization.
Cardboard (15%) —Cardboard waste is generated from packaging materials in construction and renovation projects.
Concrete and Asphalt (12%) —Concrete and asphalt waste is primarily generated during municipal and commercial projects in which buildings, roads, sidewalks, sewer works, and curbs are removed. These materials can be crushed and screened into aggregate that can be substituted for new aggregate in asphalt pavement and concrete production, as a road base, and as backfill.
Drywall (13%) —Recyclable drywall waste is generated primarily through new construction and renovation projects. See Drywall Recycling for a description of its uses.
Asphalt Shingles (10%) —Asphalt shingle waste is produced from residential new roof and re-roofing activities. See Asphalt Shingle Recycling for more details.
Other (16%) —Other building materials consist primarily of glass, metal, insulation, carpet and underlay, floor and ceiling tiles, and electrical and plumbing fixtures. These materials can be salvaged from any renovation or demolition project. Glass can be removed intact for resale, or it can be recovered and recycled. Reinforcing metals, structural metal such as building frames and metal studs, wiring, duct work, and pipes can be resold for their intended use, or can be sold to metal recyclers.