Sustainable Construction

Sustainable construction is the designing, engineering, and construction of infrastructure and buildings with the goal of optimizing environmental, social, and economic performance. Within sustainable construction, research areas include improvement of delivery methods, life cycle assessment of construction phases, waste-stream evaluation, and deconstruction of buildings.

The construction industry plays a vital role in a nation’s economic growth and resource allocation. The construction industry contributed over $639 billion to the United States' Gross Domestic Product (GDP) in 2009. The manufacturing of cement, a primary building product in construction, is a major contributor to air emissions. Moreover, in 2003 the construction industry sent 136 million tons of the solid waste to landfills, constituting roughly one-third of all the solid waste.

The nature of the construction industry is complex. Construction projects need to be expertly managed in terms of considering not only budgets and schedules, but also quality and environmental impacts. Sustainable construction research focuses on improving quality and minimizing emissions and wastes through several innovative methodologies, which are highlighted below.

Retrofit Options Through LCA

Particulate Matter from Construction

Integrating Lean, Green and Six Sigma

Understanding Retrofit Options Through LCCA and LCA

Retrofit Options

There are approximately 750,000 commercial buildings in the US North East region and of that, 85% were built prior to 1990. The astounding amount of building stock enforces the study of energy-efficient retrofits as opposed to new construction, which is less than 5% of the total building stock. Building owners need succinct deliverables that outline retrofit options in such a way that the building owner can make educated decisions on the appropriate retrofit solution.

First costs of retrofit options have the largest influence on a building owners’ decision. However, as stricter building codes, environmental standards, and accessible energy analyses become pertinent in the building sector, a more holistic understanding of retrofit options is needed. Life cycle cost assessment (LCCA) and life cycle assessment (LCA) are tools that can assess the economical and environmental impacts of a retrofit throughout its lifecycle. The combination of LCCA and LCA results can assist in the decision-making process for building owners.

A case study on a roof retrofit in Philadelphia, under the Energy Efficient Building’s Hub (a DOE program), was completed. After a design matrix was completed, two different roof options were chosen for LCCA and LCA analyses. The results were compiled in an understandable, relatable format for the building owner. The framework developed for this case study can be replicated to other building systems and should be utilized from the start of design decisions for the building owner. Understanding different retrofit decisions and maximizing efficient technologies is imperative for the future of the current building stock.

Quantification of Particulate Matter from Commercial Building Excavation

Particulate Matter

Construction activities generate large amounts of differing emissions, including particulate matter (PM). These particles are of various aerodynamic diameters, between 10 and 2.5 microns (PM10-2.5), called coarse particulates and diameters smaller than 2.5 microns (PM2.5), or fine particulates. Coarse particulates are more commonly associated with fugitive dust releases, while fine particulates are generally from the combustion of fossil fuels. The combination of construction equipment and diesel fuel combustion emissions and excavated and then exposed earth on a construction site is of particular concern with respect to PM emissions. This research developed a life cycle assessment model to quantitatively evaluate PM emissions at different scales. An illustrative case study is used to explore of the excavation phase of an urban high-rise. The excavation phase includes excavation and hauling of soil, mobilizing and demobilizing of equipment, workers commuting, delivery of fuel, handling of soil at the soil disposal site, as well as the non-regional activities of equipment manufacturing, and the production and distribution of fuels. Emissions generated at the excavation site accounted for 23% of PM10-2.5 and 13% of PM2.5 total emissions, while emissions generated over roadways accounted for 59% and 76% of PM10-2.5 and PM2.5, respectively. The majority of PM10-2.5 (89%) and PM2.5 (90%) emissions were a direct result of soil hauling activities. The results present a case for further discussion and analysis of the impacts of hauling soil on regional human health.

Ketchman, K. and Bilec, M.M. (2013). “Quantification of Particulate Matter from Construction Activities using a Life Cycle Approach.” Journal of Construction and Engineering Management, 139(12) A4013007-1 to 10. http://dx.doi.org/10.1061/(ASCE)CO.1943-7862.0000776

From Ketchman, K. and Bilec, M.M. (2013)

Integrating Lean, Green, And Six-Sigma

LG6

The construction sector is a major contributor to negative environmental impacts in the United States and furthermore consumes an abundant quantity of natural resources. In this research, an innovative model was developed with the goal of improving the life cycle environmental impacts of buildings by identifying potential waste sources prior to the construction phase, in the earliest stages of a project. The new model, called LG6, integrates three methods - Lean, Green, and Six-Sigma - and implements the Define, Measure, Analyze, Improve, and Control (DMAIC) improvement framework to environmental improvement, waste and cost reduction in construction.

The functionality of LG6 is illustrated through a case study of a woodpile installation construction process. In this case study, the LG6 model identified four steps out of eight as non-value added steps or potential waste generators according to the Lean principles. Three of the four steps involved extra time and effort by the contractor to set up equipment, while the fourth involved additional work that could have been avoided with adequate planning. For the case study, the LG6 model showed that environmental impact could be reduced by 9%—and expenses reduced by 1% as well—if alternative processes had been implemented. Specifically, the alternatives suggested would have minimized the environmental impacts of major contributors of materials, transportation, and equipment usage, in addition to helping reduce the residual waste that occurred from cutting to length all woodpiles. Quality, Costs & Impacts Process Analysis demonstrates that this case study shows the usefulness of the LG6 model on a single process and suggests that much unnecessary waste could be avoided if the LG6 model were applied extensively during pre-construction.

Banawi, A.A., Bilec, M.M. (2014). “Applying Lean, Green, and Six-Sigma Framework to Improve Exterior Construction Process in Saudi Arabia.” Journal of Construction Engineering and Project Management. 4(2), 12-22. http://dx.doi.org/10.6106/JCEPM.2014.4.2.012

Banawi, A.A., Bilec, M.M. (2014). “A Framework to Improve Construction Processes: Integrating Lean, Green, and Six-Sigma.” International Journal of Construction Management, 14(1), 58-71. http://dx.doi.org/10.1080/15623599.2013.875266

Funding Sources

Associated Publications