An Environmental Analysis of Waste Plastics Possibilities in Residential Construction

 One of the most mainstream, universally accepted, and physically manifested examples  of overall environmental degradation has become the overwhelming problem of plastic pollution.  Plastics were originally created as an extremely durable, lightweight, and cheap material.  However, their long lifespan, estimated at hundred to thousands of years (Barnes, et al. 2009),  has been relatively ignored largely in favor of disposable one-time uses. While plastics are  technically recyclable, to date, only 10% of all plastic have been recycled, with 79% ending up  in landfills or as pollution instead (Geyer, Jambeck and Law 2017). Some efforts have been  made to change policy and grassroots, consumer-based campaigns have been aimed at reducing  usage of plastic shopping bags and straws, but our plastic consumption as a nation and world  continues to rise (U.S. Environmental Protection Agency 2018). Recycling exists as a technically  feasible opportunity for change, but this is not currently taken advantage of at adequate levels in  our industry and recent changes to our international trade relationships have made this fact all the  more urgent (Brooks, Wang and Jambeck 2018). With China introducing higher contamination  restrictions on imported plastic waste and accepting 99.1% less plastic waste in 2018 than it did  in 2017, plastic waste has become an even more pressing and urgent issue (Staub 2019).  Increasingly larger amounts of plastic will end up in landfills or the ocean unless we are able to  identify greater outlets of use.  

In this context, the building industry has an interesting advantage in that it demands  materials with a longer life span as buildings have a longer use life than almost all consumer  plastics (O'Connor 2004, Murray 2018). The fabrication of recycled plastic for large-scale  architectural use can theoretically aid these problems. Existing, successful designs provide  precedents for this on a project or component basis but building construction as an industry has  yet to address its possibilities and larger environmental responsibility. Given these precedents,  the most standardized and mainstream method for using recycled plastic in buildings would be to  make standard building components out of 100% recycled material based on existing  manufacturing processes, although such products do not already exist. While precedence, such as  the work of Bureau SLA and Overtreders W, shows that this is physically feasible for a variety  of building components (Frearson 2017), analysis is required to determine if it would be  environmentally beneficial. As such, eight building components (structural framing, interior  sheeting, exterior masonry and siding rainscreens, doors, shingle and sheet roofing, and window  frames) were analyzed for environmental impact through Life Cycle Analysis combined with  consideration for either landfilling or landfill diversion of waste plastics. Through a comparison  of traditional materials and alternative, identical components produced out of recycled PET or  HDPE, it was determined that shingle roofing, sheet roofing, masonry cladding, siding cladding,  and window frames provide the best opportunities for recycling plastic waste and reducing the  environmental impact of the building industry. Based on a singular case study house (UDBS  2018), it is estimated that if all new construction, single-family, detached dwellings in the US  were to use recycled plastic sheet roofing, siding cladding, and window frames, we could save as  much as 18.3 billion kWh in fossil fuel consumption and 6.83 billion kg CO2 eq. in global  warming potential, as well as divert 1.5 billion kg HDPE waste from landfills, annually.  Alternatively, we could save 10.1 billion kWh in fossil fuel consumption and 5.36 billion kg CO2  eq. in global warming potential, as well as divert 2.1 billion kg PET waste from landfills,  annually. In one year, this could divert 27% of all annual US HDPE waste or 45% of all annual  US PET waste.