More and more, school districts are requesting that their classrooms be designed to greener standards. As a result, the modular construction industry is taking notice and using green materials, energy efficient designs, and HVAC units to accommodate the growing demand for environmentally friendly schools.

The Modular Building Institute (MBI) has modular builders from around the world as members of its association, including the leading dealers and manufacturers of modular classrooms.  MBI has also reached out to join forces with the Collaborative for High Performance Schools (CHPS) and the United States 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 modular 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, MBI recently commissioned a report titled “Modular Building and the USGBC’s LEED™ Building Rating System” that aligned the modular building industry with green building practices. The report shows that modular building offers significant opportunities for environmental stewardship in the areas of architectural engineering and construction choices. Greener building envelopes can be achieved through good site placement, the use of recycled materials and reduced waste, and better indoor air quality. In these areas, in fact, modular building offers some advantages over conventional construction.  Below is a summary.

Sustainable Sites­
Proper siting or placement of modular units can contribute to improved day lighting, 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 energy-, material- and resource-efficient project. 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 facilities are built off site in a controlled environment, worker transportation and material deliveries are centralized and streamlined, reducing the amount of energy required to construct a comparable site built facility.

Materials and Resources
Modular building by nature is material and resource efficient. One of the great economies of modular building is the ability to assemble repetitive units in controlled conditions. Another is to minimize material waste associated with conventional construction due to weather intrusion and construction site theft. Modular units, largely finished when they arrive at the construction site, can significantly limit construction waste generated at the site and contribute directly to construction site waste management.  LEED rewards projects for recognizing where materials come from, how they are used on site, whether or not they are salvaged during renovations, and how the residual waste stream is managed. Special recognition is given to using existing buildings, materials with recycled content and those that are mined, harvested, extracted and assembled within 500 miles of the construction site. Finally, LEED rewards projects that use products grown using good stewardship practice, and are lightly processed or have low embodied energy.

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.

Modern modular building construction uses a full range of materials with high recycled content. These materials are recognized for their relatively high strength to weight ratios, moisture resistance and cost effectiveness.

Indoor Environmental Quality
Superior indoor environmental quality is one of the most desirable and important attributes of high performance. At this time, the modular industry can provide both environmentally conscious buildings and eco-friendly building materials because it has control over both. This is evidenced by the creative and inspirational responses produced by manufacturers who have participated in green building design challenges.

View a complete copy of the white paper here.

In addition to modular construction being a resource-efficient, inherently greener process, it can also offer public, private, and charter schools what other construction methods cannot:  accelerated project timelines and more economical pricing.  Modular schools can also be indistinguishable from other schools and can be constructed to any architectural and customer specifications.  Any kind of building material can be used, and by using off-site technology, open construction sites are eliminated while school is in session.  Students are safer and teachers can compete with less disruption.

Case Studies
MBI annually sponsors a green student design competition.  Last year, MBI worked with Architecture for Humanity to sponsor the winner for the best relocatable classroom of the future design as part of its Open Architecture Challenge.  The winner was Druid Hills High School in Georgia for a design by Perkins+Will.  The project was designed to operate with significantly lower utility costs due to sustainable design features such as sun shades, integrated rainwater collection, photovoltaic roof panels, use of sustainable materials, generous day lighting, operable windows and natural ventilation.

Relocatable classroom design by Perkins+Will

Each year, MBI also hosts the Awards of Distinction contest, where member companies submit building entries that are judged in the areas of architectural excellence, technical innovation, efficiency, and length of project.  The winners for the last two years in the best of show green building category were modular schools.

The 2009 winner was High Tech High in Chula Vista, CA.  The school is LEED® Gold certified with the USGBC.  In addition, the school was submitted to the CHPS program.  The project includes 59 modular units totaling 32,807 square feet.

Various green materials were used to enhance classroom acoustics, day-lighting and energy efficiencies. The modular units feature various high-performance products including dual pane windows with low-E coatings, acrylic skylights, light fixtures with motion controlled sensors and low volatile organic compound paint. The project also incorporated renewable and recycled materials such as sealed lightweight concrete floors, Homasote 440 Sound Barriers, which are high-density fiberboards made from recycled newsprint that help to control acoustics in walls, and a sprayed polyurethane roof. All the materials, with the exception of the interior casework, were available locally, further reducing the carbon footprint of the project.

High Tech High by Williams Scotsman

The 2007 winner was the SmartSpace classroom, installed at the Carroll School in Lincoln, Mass., which incidentally, is the nation’s first LEED-level portable classroom.

SmartSpace classrooms use recycled steel, a blanket of rigid insulation providing thermal protection that not only moves the dew-point away from the wall and roof cavity, but exceeds ASHRAE standards. Other materials used, recycled carpet and MDF wallboard, are strategies implemented that consider renewable resources such as FSC certified plywood and bamboo, which all work together for a more environmentally responsible design package.

Optimized ventilation, C02 sensors, materials that are formaldehyde-free or have low to no VOC’s; and better natural day lighting help to make the environment a healthier, more productive place to be. High efficiency, ducted HVAC unit with occupancy sensors and energy recovery systems works in tandem with superior lighting control sensor systems that balance the infusion of natural lighting through sun tunnels with efficient artificial lighting to reduce energy consumption. TPO “Energy Star” white roofing and insulated low E glass windows with sun-shades, work to reflect or temper solar heat gain.

SmartSpace by Triumph Modular and NRB, Inc.