Introduction
Over the recent decade, sustainability has become a key concern in the construction industry. Currently, the concept of sustainability is viewed as a broad term that refers to several factors determining the impacts of both the construction process and the life cycle of the final product on the environment. The term is used interchangeably with similar, related concepts such as green building (referring both to the artifact and the process of its creation), integrated design, the whole design, and high-performance building.
In basic terms, sustainability in construction is achieved by maximizing the utility and efficiency of buildings while at the same time decreasing environmental impact. Importantly, sustainability implies a long-term perspective and requires identifying and addressing anticipated future issues and/or concerns known to occur in traditional construction projects. The following paper outlines the main approaches to sustainability in the construction industry and lists some of the materials used for the purpose.
Sustainability Methods
Currently, most of the major stages of the construction project management process have been reviewed to detect issues that may undermine their sustainability. As a result, sustainable practices have been devised for all major stages of the project life cycle. These methods can be divided into three major categories, depending on their position in the project’s timeline.
The first phase is a preliminary assessment of the project, during which its feasibility is assessed, and plans are drafted. Various organizations have suggested several methods for improving sustainability at this stage. One such method involves incorporating a green building certification system, such as LEED certification, into project needs assessment procedure and adding an environmental goal to the overall strategy of the project.
Hiring a project manager who is familiar with the concept of sustainable building and has relevant experience in the field is also highly recommended, preferably an accredited professional in the green building certification system of choice. The next step in the process would be to conduct a cost/benefit analysis that would incorporate environmental goals alongside economic targets. In specific terms, it may be necessary to assess the planned location of the construction site to identify possible environmental issues and weigh them against the needs identified in the previous phase. Verifying the alignment of both economic and environmental goals with available resources is also recommended to exclude the possibility of overruns.
Finally, with the report on hand, it becomes possible to confirm the suitability of the selected site about the needs of stakeholders and the community.
The second category includes design-related practices. For instance, in the budget planning stage, the cost estimates from contractors, project management, and the architectural department need to incorporate expenses associated with green building practices and concepts. A good example is life-cycle costs, which prioritize long-term benefits and savings before immediate expenses. The approval of the concept by the community and local authorities can also be expected to streamline the zoning approval process by regulatory organizations and minimize the need for revisions.
In the same manner, fewer barriers will be encountered during the construction documents development phase due to the integration of green concepts in the preliminary stage. Finally, receiving government permission can be expected to be simplified since most green building certification systems require compliance with guidelines used by regulatory bodies.
The third category includes methods of design implementation. One such practice is the inclusion of bonuses and incentives in contracts. The ability of architects and contractors to efficiently implement sustainable practices and exceed goals is a crucial component of sustainable construction. It is also important to ensure that the contracts include elements that specify the use of certain recyclable materials, requirements governing energy consumption, handling of excess materials, and compliance with selected provisions included in certification programs. After the launch of the project, sustainability awareness can be achieved by incorporating an educational component, such as organizing training sessions for construction site staff and involving the workforce in the on-site meetings that address sustainability progress.
Finally, the fourth category includes turning over the building for operations. At this stage, the involvement of a building commissioning authority determines the level of compliance with sustainability concepts. Communication with authority, maintained from the onset and throughout the process, makes it relatively easy to ensure that the final product functions as intended.
Materials with Sustainable Properties
Another important aspect of sustainable construction is the use of sustainable materials. In this case, sustainability refers to the ability of the material to benefit the overall cost of the project while maintaining a positive impact on the environment. This benefit may be achieved through greater longevity and durability of materials, reduced cost of maintenance and repair, lower carbon emissions during manufacturing and construction, and energy savings during the object’s life cycle, among others.
One technology that provides the described effect is concrete printing. Since its introduction, this form of 3D printing technology has demonstrated significant potential in terms of cost efficiency and versatility. In the construction industry domain, it provides an opportunity to create objects based on software-generated 3D models. The working prototypes are currently able to create objects that are superior in terms of durability, reliability, and cost compared to traditionally manufactured analogs.
Besides, printing eliminates restrictions posed by the complexity of an object’s configuration and significantly reduces waste generated in the process, leading to a lower environmental impact on the part of the manufacturing process. Finally, this technology allows for a significant degree of customization, adding to the flexibility of individual projects.
Rammed earth is another material that can be viewed as a viable option in sustainable construction. Typically, the determinants of quality of materials used for sustainable residential construction projects include the capacity for moisture and heat regulation as well as air permeability. When implemented appropriately, such materials reduce the energy expenses necessary for maintaining a desirable microclimate.
Construction blocks manufactured from rammed earth provide excellent climate control performance. Also, the manufacturing process permits air-drying, which further reduces carbon emissions. Admittedly, this type of material is only suitable for certain kinds of construction projects due to the limitations imposed by its mechanical properties. Nevertheless, in its current state, the technology offers a reasonable degree of load-bearing and resistance to weather effects.
The feasibility of the material’s use has been established in some pilot projects, including the Sheppard Theatre in Wales, where rammed earth was used to create a 23-foot wall (CAT, n.d.). Notably, the wall provides structural support to the building’s roof. More widespread use of this material is currently in the early stages due to regulatory and insurance issues linked to the novelty of the concept. Nevertheless, it is reasonable to expect its adoption in the oncoming years.
As mentioned, certain sustainable materials attain the desired effect in the long run through reduction of maintenance costs, an effect that is typically achieved by using more durable materials. However, recent advances in the industry have provided an alternative solution in the form of materials with self-healing properties. The brightest example of such materials is bio-concrete, which contains superabsorbent polymers with embedded bacteria.
The self-healing properties are achieved by the combination of mechanical, chemical, and biological effects. Cracks that appear in unhydrated bio-concrete are healed as a result of the formation of calcium carbonate crystals. Also, the microorganisms embedded in the structure will begin precipitation, eventually forming a layer of filament (GHENT University, n.d.). The structure is also reinforced with fibers that minimize deterioration and control crack propagation.
In addition to minimizing energy expenses, some materials can generate additional energy by making use of environmental sources. The most recognizable example of such technology is a solar panel, which generates electricity from solar energy. The current generation of solar elements is replacing panels with a more versatile technology of photovoltaic glazing. This new material combines exceptional physical properties with aesthetic physical appearance, allowing for use in a wide variety of projects.
The technology also generates sufficient electricity to power an average household and can be applied to a wide variety of surfaces including windows and other transparent materials (Lumira, n.d.). Even though the technology is currently in an early phase of its development, several solutions are already available at a reasonable cost, suggesting the possibility of adoption.
Another important direction of construction material development concerns thermal properties. Typically, the desired degree of thermal performance is achieved through the elimination of transparent elements, reducing light permeability and, by extension, increasing the amount of energy used for lighting. However, modern high-performance materials allow combining the benefits of non-transparent insulation with the light permeability of glass. A good example is Lumira aerogel—a material that uses translucent silica particulate to trap air in a microporous structure. As a result, the air inhibits heat transfer without sacrificing user comfort (Lumira, n.d.). Also, the material serves as a functional noise barrier, further improving its sustainable properties.
Conclusion
Sustainability is an important element of the construction process. As can be seen from the information discussed, an integrative approach is necessary to achieve the desired level of sustainability both during the process and throughout the final product’s life cycle. Sustainability can be achieved in a variety of ways, including the use of materials with superior properties, the introduction of savings, and the elimination of unnecessary actions in the process. Wider adoption of these principles will make it reasonable to expect improvements in the quality and economic feasibility of future construction projects.
References
CAT (n.d.). How was Rammed Earth Used in WISE? Web.
GHENT University (n.d.). Self-Healing of Concrete. Web.
Lumira (n.d.). Thermal Performance. Web.