Sustainable Modular Classrooms

With tighter budgets, growing classroom sizes and higher green building codes than ever, never has there been a greater need for innovative, sustainable classrooms.

The commercial modular construction industry has made significant advances in the last five years, implementing processes and materials to build and deliver more sophisticated and complex facility types. Today, the modular building industry is well poised to meet the needs of school districts, building a range of single-story relocatable classrooms or permanent, multi-story campuses of the highest quality, efficiency and design.

Due to its offsite, factory-controlled process where skilled trades apply efficient, assembly-line techniques, the modular industry is able to build and deliver healthy, safe, durable, budget-friendly, green classrooms within a short time frame that meet or exceed all building codes and specifications.

Specifically, the modular construction industry offers the following benefits that lend themselves to green building;
  1. less construction waste,
  2. minimized site disturbances,
  3. reduced construction schedules,
  4. improved indoor air quality and
  5. flexibility.

Less Construction Waste

Because modular manufacturers buy in bulk and can be working on multiple projects simultaneously at the same site, there is a much greater efficiency in terms of materials usage. Any excess materials are saved for the next project. Virtually no waste is shipped to the site, and thus ends up in landfills. Bulk materials are also stored in a protected environment safe from theft and exposure to the environmental conditions of a job site.

Minimized Site Disturbances

Because of the unique off site construction process, modular construction workers report to work at the same manufacturing facility rather than commuting to and from various construction sites. Once a project is completed in the factory, the building components are then transported to the site for installation. This process greatly minimizes the traffic from workers, equipment and perhaps most importantly, suppliers. Rather than making multiple deliveries to the site, modular manufacturers buy in bulk with fewer deliveries. 

Reduced Construction Schedules

Because construction of the building can occur simultaneously with the site work (or even before the site work), the traditional construction schedule is significantly compressed using modular.

This allows for most projects to be completed 30 percent to 50 percent sooner. The coordination of trades that occur at the factory also improves efficiency. No longer do electricians and plumbers have to wait until the entire building is framed in to begin work. No longer does the first floor need to be completed before beginning on the second. This streamlined and efficient work process results in few labor hours needed per project.

Improved Indoor Air Quality

Many of the indoor air quality issues identified in new construction result from high moisture levels in the framing materials. Because the modular structure is substantially completed in a factory-controlled setting using dry materials, the potential for high levels of moisture being trapped in the new construction is eliminated. 


When the needs change, modular buildings can be disassembled and the modules relocated or refurbished for new use, reducing the demand for raw materials and minimizing the amount of energy expended to create a building to meet the new need. In some cases, the entire building can be recycled. Modular buildings are also frequently designed to quickly add or remove one or more modules — minimizing disruptions to adjacent buildings and surroundings.

Following are case studies that demonstrate what the modular building industry can offer in terms of innovative, sustainable classrooms and schools.

High Tech High in Chula Vista, Calif.

The charter school had to meet strict indoor air quality, site design, renewable material and energy efficiency building standards in order to meet USGBC LEED, Collaborative for High Performance Schools (CHPS) and ENERGY STAR requirements. Building also had to be limited to certain areas of the site to reduce noise, pollution and habitat destruction. In addition, there was a tight budget and completion schedule for the project.

Various green materials were used to enhance classroom acoustics, daylighting 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.

The entire project was completed in only five months — at least 10 months earlier than if only conventional construction had been used. The project is also LEED Gold certified and includes 59 modular units totaling 32,807 square feet.

Performance IQ in Riverside, Calif.

The Performance IQ classroom is CHPS approved and has also been pre-approved by the CADSA (California Division of the State Architecture). It has a full steel moment-frame structure, a concrete floor, six-inch steel studs and 5/8-inch drywall underlayment, making it a strong and durable structure. Materials were selected from recycled or recyclable products as much as possible. The daylighting system leads to both energy and cost savings. HVAC costs are reduced because natural light produces less heat than artificial light.

This classroom costs less per square foot than the same classroom built with traditional construction. In addition to costing less, it can also be completed up to 40 percent faster. This classroom exceeds Title 24, California’s Energy Efficiency Standards for Residential and Nonresidential Buildings, by 26 percent in interior lighting and exceeds the total energy efficiencies in Title 24 by 40 percent. 

Davis Waldorf School in Davis, Calif.

Built in the factory in just four weeks, the Waldorf School’s new 4,000-square-foot buildings were designed by SEED (Sustainable Education Environments Delivered) for modular production. The Waldorf School’s new sustainably built kindergarten, office and multi-purpose building incorporate sustainable building practices such as no VOC interior paint for high indoor air quality, Ecobatt insulation for energy efficiency, dual flush toilets for water conservation, ENERGY STAR-rated Cool Roof for reduction in energy use and cooling costs, in addition to numerous skylights and ENERGY STAR lighting fixtures for natural lighting. The school plans to install a green roof in the future.

Harvard Yard Childcare Center in Cambridge, Mass.

The building features a variety of green, sustainable features to achieve the highest-quality, healthy environment for children. A focused design and construction plan for maximum energy efficiency includes solar tube skylights to maximize natural light use, sustainable “Green Guard” insulation, high-grade sealants and a white rubber roof that reflects solar heat. Coordinated sensors and electronic control of the lighting system turns off lights when there is no activity in the room. Other features of the child care center include exterior sun shades that shield the interior of the facility from the sun and reduce the need for air conditioning, recycled materials for the interior walls and carpet tiles, and a state of the art HVAC system that regulates and brings in air from the outside as needed.

A permanent building designed with flexibility in mind, not only is the building relocatable, but the interior paneled wall system is also flexible. Currently designed for a childcare center, the paneled walls can be taken down and reassembled to accommodate the next use — whether it is for a lab or office.

Tom Hardiman
is the executive director of the Modular Building Institute (MBI). MBI is the international non-profit trade association for commercial modular construction. For more information, visit