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Recycle Construction and Demolition (C&D) Debris
Construction Waste Handbook
Worksheet Economics
C&D Resources
Education Program
Protocol and partners
The audit for the first house began on May 26, 2004 with the setting of the two 30 cubic yard roll off containers on the site by BFI, Inc. BFI, Inc. was selected after a competitive process was conducted to secure the best pricing and agreement with the conditions of the audit. After a comparison of waste services, BFI was chosen by HARC as the waste hauler for the construction waste audits in Grogan's Point area for two reasons: 1) a pricing structure that was more favorable to the expected audit process and 2) the option to recycle wood and cardboard. HARC agreed with BFI that all dumpsters would be weighed for the HARC audits. The intended procedure for a load of material was that a HARC representative would meet the driver at the construction site and follow the truck to a Flying J service station. The truck would then be weighed. The HARC representative would then follow the truck to the recycler and observe the lumber being dumped. The truck would return to the Flying J and weigh the container and the truck empty and a weigh ticket would be provided to document the actual weight of the containerized materials.
HARC employed an intern to assist in the auditing and characterization effort. HARC trained the intern in the field methods HARC wanted to employ, and familiarized the intern with the C&D estimation process. HARC made a digital camera available to the project. HARC instructed the intern to photographically document the project virtually at will. A manual logging system to identify material and volumes was employed as the logical control mechanism for the first container that had been identified for clean sawn wood. The principal investigator and the intern routinely visited the site to inspect the logging process and to estimate the waste materials and the related volumes. The second container was reserved for additional wood materials but there was a clear recognition that the material would not be wholly sawn dimensional lumber as the first container but would contain some engineered wood.
Individual scale recycling receptacles were purchased and placed on site for aluminum, plastic, glass and trash with hopes to mitigate trash entering the study at inappropriate times. The construction superintendent allowed HARC to speak to the onsite crews and explain the project objectives and the role that they could play in the project. The intern visited the site everyday, and if necessary segregated waste and hauled trash.
 Figure 12. Individual receptacles Click image above for a hi-res version |
 Figure 13. First wood, forms package Click image above for a hi-res version |
June 2004 was the wettest June on record for the state of Texas, according to NOAA (http://www.noaanews.noaa.gov/stories2004/s2265.htm) with 20 days of rain recorded at Bush Intercontinental Airport (http://www.srh.noaa.gov/hgx/climate/iah/jun04iah.txt). The large amounts of rain and frequent storms during June significantly slowed the pace of construction, and correspondingly caused large delays in the audit.
 Figure 14. Wettest June Click image above for a hi-res version |
 Figure 15. Dumpster diving Click image above for a hi-res version |
Also, to make the site ready, the builder had to purchase and apply crushed concrete to the site to facilitate access. Work proceeded slowly and framing was not complete until July 17, 2004. The intern spent a fair amount of time "dumpster-diving", packing, stacking and cleaning out the first 30 yard roll off container. Our plan for the audit contained two components. The first step was to estimate the volume and weight of the waste material using the EPA's fairly simple estimation tool and secondly, to run the C&D waste containers over a set of scales (full and empty) to obtain the actual weights of the material. This would afford us an opportunity to compare the predicted weights using the EPA methodology versus the actual. This would help us determine whether it made any sense to employ the tool in the handbook and training, which was required in the contract.
The planned methodology worked for the first container and all other containers in this audit but failed for the second container. This failure was a huge disappointment and a complication that was not anticipated. The plan failed when the contractor's dispatcher failed to instruct the driver of the procedure to drive the truck and container over the scales. The dispatcher also had failed to tell the driver that the haul was clean wood and subsequently all of the material was land filled instead of recycled. This event was witnessed by the intern who raced after the driver and the container, through toll booths and to the gates of the landfill only to be just a little too far behind the driver for the waste contractor to ever have know that he was being pursued. Subsequently, the dispatcher was fired for this and other issues.
Methodology
HARC made use of a calculator frequently cited by the EPA, adapted from a NAHB research project. The calculator converts the volume of materials into pounds. Understanding the waste stream requires us to use consistent units. Since drywall is far denser than cardboard, a dumpster full of drywall will weigh far more than a dumpster of cardboard, hence the need of conversion factors. The following table presents the conversion factors employed by HARC in this process whenever actual weights were not possible to obtain.
| Table 5. Conversion factors used by HARC |
| Material | Pounds per Cubic Yard |
Cubic Yards per Pound |
| Solid Sawn Wood | 267 | 0.004 |
| Engineered Wood | 280 | 0.004 |
| Drywall | 400 | 0.003 |
| Cardboard | 30 | 0.033 |
| Metals | 150 | 0.007 |
| Asphalt Shingles | 400 | 0.007 |
| Masonry | 1000 | 0.001 |
| Paints, Caulks, etc. | 167 | 0.006 |
| Mixed Wastes | 95 | 0.010 |
HARC attempted to carefully estimate the quantity of wood emptied and stacked into the first container. The values employed were 267 pounds per cubic yard for solid sawn wood and 280 pounds for engineered wood products as shown in the table above. This is one of the most problematic areas in the study as there is great variability in weights as a result of the packing density of the containers, most often based upon the sizes and shapes of the waste itself. In the instance of the first and second containers of Waste Stream Audit One, the packing was particularly tight because HARC hand sorted and packed the containers. Thus, the actual weight for the first container was much higher than the calculators predicted weight. The variance is a result of an assumed degree of unfilled volume by the calculator.
This presumption becomes more problematic later in the audit. In later hauls, the nature of the density and/or the increase in the amount of loose wood or other materials contributed to the container's volume being utilized but the weight is significantly less than those first two hauls. Thus, the volume for the container remains the same at 30 cubic yards but the weight of the later haul containers is reduced greatly and more nearly matches the expected weights from the EPA calculator.
Audit Process and Findings
Haul One
Haul Number One was conducted on July 12, 2004. The assumption of a field estimated 27.9 cubic yards of material filling a 30 cubic yard container was utilized. Field estimation of volume was based on observance and the manual log which construction workers were asked to execute as they filled the containers.
Utilizing the EPA calculator, this haul consisted of: (1) forms from the slab, solid sawn wood equaling 4,272 pounds (16 cu yards * 267 lbs/cu yd) and (2) framing timber, solid sawn wood equaling 3,177 pounds (11.9 cu yards * 267 lbs/cu yd) for a total predicted weight of 7,449 pounds.
When the truck and container passed over the scales, the weigh ticket resulted in 11,100 actual pounds. The variance of actual to predicted weights was 3,651 pounds. When the container was reset on the site, HARC reserved the container for the upcoming shingle phase of the project.
| House One Landfill Waste |
| Date | Haul | Weight (lbs) | Details |
| 7/12/2004 | 1 | 11,100 | Frame |
 Figure 16. End cuts of lumber Click image above for a hi-res version |
 Figure 17. Solid sawn wood content from haul one Click image above for a hi-res version |
 Figure 18. Solid sawn wood content from haul one Click image above for a hi-res version |
Haul Two
Haul Number Two, conducted on August 3, 2004, consisted of: (1) rafters, solid sawn wood equaling 2,376 pounds (8.9 cu yards * 267 lbs/cu yd) and (2) roofing sheathing, an engineered wood product, equaling 5,068 pounds (18.1 cu yards * 280 lbs/cu yd).
| House One Landfill Waste |
| Date | Haul | Weight (lbs) | Details |
| 8/3/2004 | 2 | 7,444 | Rafters & sheathing |
Again utilizing the EPA calculator HARC calculated a predicted weight of 7,444 pounds with a field measured 27.0 cubic yards of material filling a 30 cubic yard container. Haul Two turned into a runaway 30 yard roll off container. As a result, no actual weight is available and the clean wood was taken to a landfill. When the container was returned to the site, it was earmarked for its next load to be the remaining wood, cardboard and mixed use container.
 Figure 19. Solid sawn wood Click image above for a hi-res version |
 Figure 20. Engineered wood including TechShield Click image above for a hi-res version |
 Figure 21. Engineered wood including TechShield Click image above for a hi-res version |
Haul Three
During the month of August the structure was being enclosed ("dried in"), meaning the sheathing and the shingles were being installed. Interestingly enough, the EPA calculator based upon the NAHB study did not include shingles' calculation. Therefore, HARC conducted an extensive web search and concluded that the appropriate value for use in this H-GAC study, while being consistent with the EPA calculator was 400 pounds per cubic yard. As Haul Three was about to take place, the calculator's value for commingled or mixed waste became an issue as a frequent problem that confronts builders appeared in our study. The neighbors by this juncture decided the containers were for public use and began to dump their trash into them with impunity. Since the container was primarily full of shingles, HARC chose the mixed waste calculator value of 95 pounds per cubic yard because the commingled waste included a significant amount of the very light polystyrene sheathing.
Haul Three was conducted on September 10, 2004. Haul Three consisted of: (1) shingles equaling 10,800 pounds (27 cubic yards * 400 lbs/cu yd), and (2) mixed wastes equaling 266 pounds (2.8 cubic yards * 95 lbs/cu yd) for a total predicted weight of 11,066 pounds with a field measured 29.8 cubic yards of material filling a 30 cubic yard container.
| House One Landfill Waste |
| Date | Haul | Weight (lbs) | Details |
| 9/10/2004 | 3 | 12,080 | Shingles & some commingled |
The weigh ticket resulted in 12,080 actual pounds. The variance of actual versus predicated weight was 1,014 pounds. When the container was returned it was earmarked to contain drywall debris next.
 Figure 22. Asphalt shingles from Haul Three Click image above for a hi-res version |
 Figure 23. Asphalt shingles from Haul Three Click image above for a hi-res version |
 Figure 24. Asphalt shingles from Haul Three Click image above for a hi-res version |
Haul Four
Haul Four was also conducted on September 10, 2004. Haul Four consisted of: (1) solid sawn wood equaling 2,136 pounds (8 cubic yards* 267 lbs/cu yd), (2) engineered wood equaling 560 pounds (2 cubic yards* 280 lbs cu yd) and (3) cardboard (19 cubic yards* 30 lbs/cu yd) equaling 570 pounds for a total predicted weight of 3,266 pounds with a field estimated 29 cubic yards of material filling a 30 cubic yard container.
 Figure 25. Solid sawn wood and cardboard from Haul Four Click image above for a hi-res version |
 Figure 26. Solid sawn wood and cardboard from Haul Four Click image above for a hi-res version |
 Figure 27. Solid sawn wood and cardboard from Haul Four Click image above for a hi-res version |
The weigh ticket for this 30 cubic yard haul was 3,040 pounds. The variance of actual versus predicated was – 226 pounds. Upon return, the container was identified as the bricks and mortar container.
 Figure 28. More wood and cardboard from Haul Four Click image above for a hi-res version |
 Figure 29. More wood and cardboard from Haul Four Click image above for a hi-res version |
 Figure 30. More wood and cardboard from Haul Four Click image above for a hi-res version |
| House One Landfill Waste |
| Date | Haul | Weight (lbs) | Details |
| 9/10/2004 | 4 | 3,040 | Cabinets, cardboard, some wood |
Haul Five
Progress on the house was moving along rather quickly during the September 2004 timeframe. The masons had arrived and began the process of bricking the home, and the drywall (sheetrock) crew arrived to begin sheet rocking the interior space. Both of these processes generate an enormous amount of waste compared to early processes and corresponding time frames.
Haul Five took place on September 21, 2004 and consisted primarily of brick, and mortar. Utilizing the EPA calculator HARC estimated the container consisted of: (1) 9,000 pounds of bricks and mortar (9* 1000 lbs/cu yd) and (2) 270 pounds of cardboard (9* 30 lbs/cu yd.) for a total estimated weight of 9,270 pounds. The weigh ticket for this container was 9,460 pounds. The variance of actual versus predicted weight was 190 pounds. When the container was returned it was again designated as a brick and mortar receptacle for the next haul.
 Figure 31. Bricks on-site Click image above for a hi-res version |
 Figure 32. Bunks of Brick Click image above for a hi-res version |
| House One Landfill Waste |
| Date | Haul | Weight (lbs) | Details |
| 9/21/2004 | 5 | 9,460 | Brick, Mortar, Dirt |
Haul Six
Haul Six took place on October 4, 2004. Haul Six was a drywall only container. Again, making use of the tally sheet and the EPA calculator, HARC estimated the container to be composed primarily of drywall in the amount of 28 cubic yards of material, with an estimated weight of 11,200 pounds (28* 400 lbs/cu yd). When the container passed the scales it weighed in at 12,820 pounds for a variance of 1,620 pounds.
| House One Landfill Waste |
| Date | Haul | Weight (lbs) | Details |
| 10/4/2004 | 6 | 12,820 | Drywall |
 Figure 33. Drywall (sheetrock) from Haul Six Click image above for a hi-res version |
 Figure 34. Drywall (sheetrock) from Haul Six Click image above for a hi-res version |
Haul Seven
HARC did not attempt to estimate the weight for Haul Seven. We knew from the foreman that the waste from the "lot clearing" was coming and there was no reliable method to do the calculation for what was anticipated. We felt this was a reasonable decision considering what took place as depicted from the pictures below in Figures 35-37.
Haul Seven took place October 28, 2004. The contents of the container consisted of the second phase of the lot clearing and the final cleanup of the wood waste from the site. The container also held all wooden palettes and the wood (trim) from the interior spaces. This container had been intended to be a wood waste container. Haul Seven was scaled at 8,940 pounds and is pictured below.
| House One Landfill Waste |
| Date | Haul | Weight (lbs) | Details |
| 10/26/2004 | 7 | 8,940 | Brush, pallettes |
 Figure 35. Contents of Haul Seven: lot clearing, palettes, and a tire! Click image above for a hi-res version |
 Figure 36. Contents of Haul Seven: lot clearing, palettes, and a tire! Click image above for a hi-res version |
 Figure 37. Contents of Haul Seven: lot clearing, palettes, and a tire! Click image above for a hi-res version |
Haul Eight
Haul Eight took place on December 13, 2004. The container contents were primarily of concrete, bricks, mortar and cardboard. HARC did estimate this container. The estimate was a very full 30 cubic yards consisting of: (1) concrete and bricks equaling 12,000 pounds (12 cubic yards* 1,000 lbs/cu yd) and (2) cardboard equaling 510 pounds (17 cubic yards* 30 lbs/cu yd) for a total predicted weight of 12,510 lbs with a field estimated 30 cubic yards of material. The haul scaled out at 13,720 pounds, by far the heaviest of any haul made in the project. Apparently some of the flat work was not acceptable and discarding it was the easiest way to handle the issue (see figures below).
| House One Landfill Waste |
| Date | Haul | Weight (lbs) | Details |
| 12/13/2004 | 8 | 13,720 | Concrete & Bricks |
 Figure 38. The unacceptable flatwork Click image above for a hi-res version |
 Figure 39. Mixed contents of Haul Eight Click image above for a hi-res version |
 Figure 40. Cardboard en mass Click image above for a hi-res version |
Haul Nine
Haul Nine took place on January 5, 2005. Utilizing the EPA calculator, this haul consisted of: (1) site cleared wood 3,738 pounds (14 cu yards * 267 lbs/cu yd) and (2) interior trim wood, solid sawn wood equaling 2,403 pounds (9 cu yards * 267 lbs/cu yd) and (3) cardboard equaling 210 pounds (7 cu yards * 30 lbs/cu yd) for a total predicted weight of 6,351 pounds. The container was actually scaled at 6,820 pounds. The container held the final site clearing debris, the interior trim package waste and all remaining discarded cardboard on the site.
| House One Landfill Waste |
| Date | Haul | Weight (lbs) | Details |
| 1/5/2005 | 9 | 6,820 | Trim, brush, cardboard |
 Figure 41. Haul Nine Click image above for a hi-res version |
 Figure 42. Interior trim wood, solid sawn wood Click image above for a hi-res version |
Summary of House One
In total, the house generated 85,242 pounds of C&D waste. According to the national average based on NABH studies, a typical 2,000 square foot house generates 8,000 pounds of waste. This is verified in previous studies and confirmed in the Franklin report. This house was 7,929 square feet. If we were to extrapolate the 2,000 square feet to 8,000 square feet one would expect something on the order of 32,000 pounds of C&D waste.
| House One Total Landfill Waste |
| Date | Hauls | Weight (lbs) | Yards |
| 7/2004-1/2005 | 9 | 85,242 | 247.7 |
This study did not even come close with its 85,242 pound total. Our differential from the expected result is 53,242 pounds. That is a 266.4% variance from the expected result. The pie charts in Figures 43 and 44 below depict the ratios of waste make up for the study house and the national typical house. One of the striking differences in the two charts is the 236% increase in the brick component of the C&D waste stream. This is significant inasmuch as, according to the EPA calculator, bricks weigh an estimated 1,000 pounds per cubic yard. This is an indicator of the primary cause in the variance. The fact that H-GAC area's modern hot and humid houses typically are built with a significant increase in the volume of enclosed space leads to this surprisingly large increase in the amount of material required to create the envelope and the resultant interior components such as drywall. This is simply a function of geometry that builders are forced to deal with in this marketplace. To illustrate this point is the following example. If a wall section is 10 feet high in a modern hot and humid climatic zone house and the comparison circa 1996 national typical is an 8 foot wall section, then 25% more material is required to cover the same square footage of space.
The fact that there is a variance should not come as any surprise due to the response to climatic differences in the nation's typical house versus the typical house in the hot and humid area. The surprise comes in the enormity of the variance. It is curious that the shift in materials (-28%) away from wood and drywall is fully accounted for in the increase in the percentage of bricks and masonry used. We have some opinions about the possible causes of the variance and suggest them in the following observations section.
 Figure 43. C&D waste-stream makeup |
 Figure 44. C&D waste-stream makeup |
Waste stream disposal costs
The total expenditure for waste stream disposal costs totaled $1,800; $180 to set the two containers on the site and $180 per haul for nine hauls.
 Figure 45. Completed House One Click image above for a hi-res version |
Observations
Designing Out Waste
- Material quantities for building are significantly overestimated, therefore ensuring a waste stream.
- The utilization of bricks for facade and as an element of mass, when applied to the notion of 10 foot or greater wall sections, creates a geometric problem that can only be remedied by significantly more material.
- Complicated and complex elevations and roofing options lead to a large amount of brick and shingle waste.
- Bricks are oversupplied to the jobsite by a factor of about 15% to allow for quality, batch variation and breakage.
- A total of nine (9) dump truckloads of crushed concrete were purchased and applied to the site so workers could gain semi reasonable access.
- The slab contractor generally reuses wood from the forms for about four sites and dumps the waste wood at the fourth. Most of this wood was left on our audit site.
- The days lost to rain are many and they are costly in terms of waste generation.
- Less than sixty days into the construction, after the initial seven truckloads of crushed concrete, another 2 dump truckloads were required to maintain access to the site.
- Total site cleanup costs are about 1% of the total sales price of the home, with 20% of that percentage being paid to the waste haulers. In this house that equates to $ 2,000 for the waste company and $ 8,000 paid to common laborers to effectuate the cleanup.
- Neither efficiency nor effectiveness were principles that were deeply held in this process of residential house building.
- Time is the one dimension that we observed the craftspeople valuing.
- The builder values profit first and foremost. If he can't make money he will not engage in the act.
- The EPA calculator tool is a workable, reasonable estimation tool based upon this data and H-GAC should make use of it for their purposes.
- Estimating volumes is not difficult to perform, if you are willing to accept a small margin of error.
- Volumes are dramatically affected by density.
- Waste management is not specified as one person's job at the site.
- The foreman is the most important person in a C&D waste study.
- Given the choice, workmen will always choose virgin material over looking for scrap or surplus.
- The weakest link in the study in terms of cooperation, difficulty to work with, and communication was the waste firm.
- If you post notices in Spanish, workmen will read them.
- Hispanic workers will recycle when skilled Anglo tradesmen will not.
- If you provide waste receptacles on the jobsite and the foreman requires workmen to use them, they (the workmen) will.
- Clean wood waste is hauled to a wood recycling firm when the driver is instructed to do so by the dispatcher.
- There is a small underground economy in clean wood waste that is profitable.
- The cost to haul C&D waste is very small and represents less than 0.5% of the selling price of a home.
- The "roach coaches" that bring the workmen breakfast and lunch, should be required by license to provide on the vehicle trash receptacles and recycling bins.
- The larger the waste container, the larger the temptation for everyone on or near the site to not be responsible about waste on the site.
- The public thinks that a waste container in the neighborhood is a free dumping zone. As a solution to remedy this problem, the threat of video taping illegal dumping should be exercised routinely.
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