With the mounting concerns for environmentally safe practices in the commercial building industry, one of the biggest challenges that conventional construction increasingly faces is excess waste and lack of innovative practices to minimize and recycle it. According to the statistics from the US Office of Solid Waste, Building-related construction and demolition (C&D) debris totals approximately 160 million tons per year, accounting for nearly 26 percent of total non-industrial waste generation in the U.S. Sources of the building-related C&D debris waste-stream include demolition (accounting for approximately 48 percent of the waste stream per year), renovation (44 percent), and new construction (8 percent). (Source: http://www.epa.gov/greenbuilding/pubs/gbstats.pdf PDF file) This astounding amount of waste can in great part be attributed to the fact that architects and builders do not design commercial and residential structures with easy re-purposing or deconstruction in mind. However, in recent years modular construction industry has emerged as a pioneer in successfully employing a completely different approach to waste management- one that saves money and helps our environment.
A common practice in onsite construction is to focus on recovery, reuse, recycling or diversion of waste only post-construction. This turns out to be highly ineffective and a lot of energy and materials that could have been put to better use simply get wasted, while builders foot the additional cost. A staggering 135 million tons of construction debris ends up in our overflowing landfills every year. Modular construction has taken a completely different approach to reducing waste at the front end by using a number of smart practices such as improved management, efficient materials procurement and streamlined production practices. Moreover, modular buildings are uniquely designed to have a longer service life. Instead of being demolished or abandoned, buildings and their components can be easily deconstructed and reused. These practices combined greatly minimize the total amount of construction waste, and what is left over can then be recycled or disposed of. Overall, waste management practices employed in the modular construction industry offer more environmentally sustainable building solutions.
The difference of prefabricated construction
The very nature of modular construction makes it an energy and materials efficient process. The production of modules is streamlined and controlled every step of the way, making it possible to execute very tight inventory control that leaves very little room for waste. Additionally, a factory controlled environment makes it possible to have a number of construction projects going on simultaneously. This makes it possible to re-inventory materials and immediately allocate them for another project if the need arises. By comparison, with on site construction, a project manager simply sends any extra materials to the recycle facility or the dump. Moreover, in a factory environment it is much easier to account for and protect materials, keeping them safe from getting stolen, lost or damaged by inclement weather (all common incidents in onsite construction). All of these mechanisms greatly reduce the amount of building materials that would otherwise be wasted and dumped into landfills.
Less waste on site
It is not surprising that prefabricated models also create less waste once they arrive on site. Since they come in as whole modular units – largely finished prior to arriving at the construction site, there is significantly less waste generated in the final stages of the onsite construction process. Moreover, because modular construction is inherently waste conscious, effort is made to deliver modules in careful and strategic ways that will have minimum site impact and waste. Thus, since there is overall less waste, it also becomes easier and cheaper to manage it properly.
The WRAP report clearly demonstrates that up to a 90% reduction can be achieved by reducing wastes such as wood pallets, shrink wrap, cardboard, plasterboard, timber, concrete, bricks and cement by increasing the use of off-site modular construction.
Less room for human error
Modular construction helps reduce waste by minimizing the amount of worker errors and the need for re-work. Mistakes and poor workmanship quality, which are rampant in onsite construction, also greatly contribute to the overall amount of waste. These issues are largely eliminated in modular construction- the streamlined, repetitive manufacturing process results in a much higher quality of workmanship and leaves little necessity to redo any parts of a project.
Designed for reuse
One of the key principles that set modular construction apart from its competitors is the fact that modules are designed to be re purposed many times beyond the scope of the initial project. This concept challenges the accepted norms and standards of the construction industry where a building is expected to have an end to its service life, after which it is either demolished or simply abandoned. Typically, it is too costly to try to reuse or recycle parts of these unwanted structures, so waste is an expected component of a building’s end of service life. Not so in modular construction. Every module itself and the building as a whole is specifically designed for easy deconstruction, removal and reuse in other projects. It is truly innovative that the process by which the building was installed can literally be reversed: the building can come apart in pieces in the same way it was created. In this manner, modular construction strives to model after the best practices of mother nature: where nothing is wasted and every element continues to serve a purpose in the life-cycle of the planet.