7.4 Construction and Demolition Waste Management
Key Takeaways
- MR Credit: Construction and Demolition Waste Management is worth 1-2 points and goes beyond the prerequisite by requiring measured diversion.
- Path 1 awards 1 point for diverting at least 50% of total C&D waste across at least 3 streams, and 2 points for at least 75% across at least 4 streams.
- Path 2 awards 2 points for reducing total C&D waste generation to no more than 12.5 pounds per square foot of building floor area.
- Diversion percentage equals diverted weight (or volume) divided by the sum of diverted plus landfilled weight (or volume); only one unit is used consistently.
- Alternative Daily Cover (ADC) counts as landfill, not diversion, regardless of how the hauler reports it; land-clearing debris and hazardous waste are excluded from the calculation entirely.
From Plan to Performance
Where the MR prerequisite required a plan, this credit requires measured results. Two compliance paths are available — Path 1 (diversion percentage) and Path 2 (waste reduction per square foot). A project chooses one.
Path 1 — Diversion of C&D Waste
Divert the listed minimum percentage of total construction and demolition waste from disposal across the listed minimum number of streams.
| Diversion | Minimum Streams | Points |
|---|---|---|
| 50% | 3 | 1 |
| 75% | 4 | 2 |
What Counts as Diversion?
- Recycling (off-site at a permitted facility)
- Salvage and reuse on the same project
- Salvage and reuse off-site (donation to other projects or organizations)
- Wood chipping or composting for landscape use
What Does NOT Count
- Alternative Daily Cover (ADC) — counts as landfill.
- Land-clearing debris (stumps, soil) — excluded from numerator and denominator.
- Hazardous waste — excluded; handled under federal/state regulations.
- Excavation soils — excluded.
- Materials sent to waste-to-energy facilities — typically excluded, although some regional definitions vary; LEED counts these as landfill unless the LEED Interpretation database states otherwise.
Streams
A stream is a single material type that is separately diverted. Typical streams on a commercial project: concrete, metals, wood, gypsum board, cardboard, asphalt, brick/masonry, carpet. To earn 2 points, at least 4 separate streams must be diverted — a project that diverts 90% in concrete only would not qualify because it relies on a single stream.
Path 2 — Reduction of Total Waste Generation (2 points)
Reduce total C&D waste generated to no more than 12.5 pounds per square foot (61 kg/m²) of building floor area. This path rewards designs that prevent waste at the source through prefabrication, modular construction, accurate cut lists, and just-in-time delivery. Path 2 is the only way to earn 2 points without sorting streams on-site.
Calculating Diversion Percentage
Use one unit consistently — either weight (tons or pounds) or volume (cubic yards). Do not mix.
Diversion % = Diverted Weight ÷ (Diverted Weight + Landfilled Weight)
Worked Example 1: Single Stream
A project sends 400 tons of concrete to a recycling facility and 100 tons of mixed debris to a landfill. Diversion = 400 ÷ (400 + 100) = 80%. If the project also diverted at least three additional streams above token amounts, it would qualify for the 75% / 2-point threshold. With only one stream, it qualifies for 0 points under Path 1 — stream count rules the day.
Worked Example 2: Multiple Streams
| Stream | Generated (tons) | Diverted (tons) | Landfilled (tons) |
|---|---|---|---|
| Concrete | 100 | 80 | 20 |
| Wood | 50 | 45 | 5 |
| Metal | 30 | 30 | 0 |
| Drywall | 20 | 15 | 5 |
| Total | 200 | 170 | 30 |
Diversion = 170 ÷ 200 = 85% across 4 streams → 2 points under Path 1.
Worked Example 3: ADC Trap
A hauler reports 1,000 tons of waste with 600 tons recycled, 200 tons used as Alternative Daily Cover, and 200 tons landfilled. Under LEED, ADC = landfill, so diversion = 600 ÷ 1,000 = 60%, not 80%. This is a frequent audit catch.
Commingled Recycling and Facility Rates
If the project uses a commingled (mixed) waste hauler, the diversion percentage is the facility's published material recovery rate for that stream. The hauler must provide a third-party-verified rate (often 60-75% for clean MRFs). Source-separated diversion typically scores better than commingled because more material is recovered.
A LEED BD+C project generates 800 tons of construction waste. Of that, 520 tons are recycled across 5 separated streams, 80 tons are sent to a landfill as Alternative Daily Cover, and 200 tons are landfilled. Under Path 1, how many points does the project earn?
A 100,000-square-foot project pursues Path 2 of MR Credit: Construction and Demolition Waste Management. What is the maximum total C&D waste the project can generate while still earning 2 points?