The Greening of Portable Classrooms
By: Tom Hardiman
There is a great deal to be excited about when it comes to portable classrooms and their fit into a sustainable future. The industry has reached out to join forces with the likes of the Collaborative for High Performance Schools (CHPS) and the U.S. Green Building Council (USGBC) as the green movement has gained momentum. These affiliations are starting to yield tangible results as companies adopt cost-effective ways to implement energy-saving portable classroom designs.
With the construction of green modular classrooms, there is a growing awareness of the inherently green features of the modular construction process. In fact, the Modular Building Institute recently commissioned a reportthat aligned the modular building industry with the Prerequisite and Credit requirements imbedded in the United States Green Building Council’s (USGBC’s) Leadership in Energy and Environmental Design (LEED) building rating system. The report, Modular Building and the USGBC’s LEED Building Rating System, looks at LEED for New Construction and Major Renovations, applied to commercial construction, and LEED for Schools.
The report shows that modular building offers significant opportunities for environmental stewardship and LEED certification, particularly in the area of architectural engineering and construction choices.
This article will summarize the report’s overall conclusions concerning modular construction and sustainability as it relates to the following LEED prerequisite and credit categories.
Sustainable Sites
Proper siting or placement of modular units can contribute to improved daylighting, natural ventilation, better storm water management, more efficient site lighting, and a host of other sustainable design and development improvements that contribute to a more efficient project with regard to energy, materials, and resources.
This category also rewards construction techniques that limit site disturbance and keep disturbed areas to within the areas immediately adjacent to the building footprint. Because modular building units are fabricated off-site and delivered by a variety of over-the-road transport, it is possible to achieve tighter site control and less disturbed area in the project perimeter.
Water Efficiency
Water conservation is one of the hallmarks of high-performance green buildings and one area where modular building can enjoy the same benefits as conventional construction. Rainwater harvesting systems can be integrated into modular building designs. Ecologically sensitive landscaping, intelligent plant selection, integrated pest management, and sensitivity to the microclimates buildings create when sited are universal principles and practices that apply to all construction.
Energy and Atmosphere
Increasing energy costs and growing concern about energy availability and security are sure to keep the interest in energy conservation and renewable or alternative energy sources in the forefront of the high-performance green building movement.
Modular building has a number of potential advantages over conventional construction in this category:
* Modular construction can produce relatively high R values and low infiltration rates if fabricated and constructed with good quality control.
* Steel and aluminum stud frame construction can also produce energy-efficient units if care is taken to insure proper installation techniques and air sealing.
* High-performance windows contribute to the pursuit of high-performance building envelopes in each case, as do proper air sealing procedures and quality entrance systems.
Modular building manufacturers can also point to superior energy conservation and reduced operating costs as a function of quality control in factory environments, as opposed to conventional construction where both labor and materials can be subject to the influence of weather.
Materials and Resources
One of the significant economies associated with modular construction is the ability to manage construction waste. LEED rewards construction waste management at the construction site by being able to account for the materials, by weight or by volume, that are diverted from landfills. This includes all non-hazardous materials, excluding cut and fill and organic material removed from the site.
One direct benefit of reducing the overall waste stream is the simplification of construction waste management at the site and the attendant reduction in dumpster costs and hauling fees. In the case of modular building, overall construction waste generated at the site can be reduced significantly.
Indoor Environmental Quality
Superior indoor environmental quality is one of the most desirable and important attributes of high performance. The modular building industry has control over both the materials and quality control features that provide superior building atmospheres. This is evidenced by the creative and inspirational responses produced by modular building manufacturers that have participated in green building challenges.
Several modular building providers have won competitions for their buildings that demonstrate superior indoor air quality is possible with informed design and construction choices and quality construction.
This category also looks to the proper IAQ during the actual construction of buildings. In modular building manufacturing plants, the conditions are often ambient, reducing the need for supplemental space conditioning during construction. The assembly areas are not subject to excessive moisture or extremes in temperature and are generally controlled to provide acceptable working conditions.
Innovation and Design Process and LEED
Perhaps the best feature of the LEED building rating system is the invitation to be innovative. It underscores that fact that all buildings, including modular buildings, are simply what we make them.
Modular building capitalizes on the ability to move product in controlled manufacturing conditions, tight inventory control, and project schedules. It is inherently waste conscious and can have minimum site impact if delivered carefully and strategically with respect to site constraints.
Modular units purchased within 500 miles of the construction site offer other LEED point opportunities, as does the reality of installing low VOC materials on site.
Note: To review a complete copy of the white paper, Modular Building and the USGBC’s LEED Building Rating System, visit modular.org.
Tom Hardiman is the executive director of the Modular Building Institute based in Charlottesville, Virginia. The Modular Building Institute (MBI) is an international non-profit trade association representing providers of commercial modular buildings, including portable and modular classrooms, www.modular.org.
