1 DECEMBER 2002
Initially, additional time will be required for contract development. Once a recycling
contract has been developed and accepted, future contracts for recycling can be readily
implemented and contract development is no longer a factor.
3-2.3 Recover (Time). Recovering building materials for reuse is a viable option when
time is not constrained. The time involved in handling, sorting, cleaning, cutting, and
selling second hand building materials is substantial and can undermine the feasibility of
salvage at a demolition job. Duration on-site depends on the extent of the recovery and
hand labor required to extract recoverable materials. Extra care and time must be taken
to reduce the chances of damaging the materials as they are removed. Separating and
sorting materials as they are recovered from the building will increase the total time for
on-site removal, but will produce higher quality materials and much higher financial
returns. References for deconstruction can also be used for determining the time
requirements for recovery. These references are included in the paragraphs below.
3-2.4 Deconstruct (Time). Relocating or removing the entire building intact and
panelized deconstruction, are rapid forms of deconstruction. However, manual
deconstruction is labor intensive and will naturally increase the overall duration of the
project. The time requirements for disassembly may vary between three to eight times
that of mechanical wrecking. Case studies conducted in the military and private sector
show that manual deconstruction proceeds at a rate of about 0.3 SF per man-hour for a
wood frame building. For example, a 3,600 SF typical wood frame WWII building, at 0.3
SF per man-hour, with a 10-person crew, requires roughly 3 weeks to manually
deconstruct. This figure includes handling, on-site processing and project management
and is consistent with R.S. Means productivity data.
Table 3-4 lists labor hours recorded for the disassembly and salvage of components
from a 2,000 square foot building made up of four residential units that was
deconstructed as part of the Riverdale Case Study. The Riverside Case Study was a
multi-agency (EPA/NAHB/HUD) deconstruction project in Baltimore that implemented
These labor hours can be used in combination with more comprehensive references,
such as R.S. Means Building Construction Cost Data, Micro Computer-Aided Cost
Engineering Systems (MCACES), and a Job Order Contracting (JOC) handbook for
estimating deconstruction/demolition square foot costs.
Table 3-4. Labor Hours for Disassembly and Salvage of a 2,000 SF Building.
Disassem Processi Supp Compone