Summarizes research aimed at improving indoor air quality and reducing noise and energy consumption of relocatable classrooms. Researchers have developed specifications for an improved heat-pump air-conditioning system that provides a seasonal energy-efficiency rating (SEER) of 13. Field tests revealed that the units are superior to conventional units that are currently used in relocatable classrooms because they improve indoor air quality, save energy, operate more quietly, and provide similar or better thermal comfort. Although the study primarily focused on relocatable classroom applications, the wall-mounted packaged units are designed to fit on any modular or portable buildings for both new construction and retrofit applications and can be used in most U.S. climates. 2p.

Discussion of the use of more durable portables in Palm Beach County, Florida. Concrete units are being explored as a safer, cost-effective, and more durable option to easily damaged traditional classroom portables. The portables feature, reinforced roofing, impact-resistant windows, and are rated to withstand winds of 187 mph. Concrete portables can be integrated into a modular design and can be configured to almost any shape or for any purpose. 3p.

Reports on principals' satisfaction with environmental factors in their schools, and the extent to which they perceive those factors as interfering with the ability of the school to deliver instruction. The report describes the match between the enrollment and the capacity of the school buildings, approaches for coping with overcrowding, the ways in which schools use portable buildings and reasons for using them, and the availability of dedicated rooms or facilities for particular subjects, such as science labs or music rooms, and the extent to which these facilities are perceived to support instruction. More than half of the principals reported that their school had fewer students than the school’s design capacity. The remaining schools included those that had enrollments within 5 percent of their capacity (22 percent) and those that were overenrolled (10 percent were overenrolled by between 6 to 25 percent above their capacity, and 8 percent by more than 25 percent of their design capacity). Those schools that principals described as overcrowded used a variety of approaches to deal with the overcrowding: using portable classrooms (78 percent), converting non-classroom space into classrooms (53 percent), increasing class sizes (44 percent), building new permanent buildings or additions to existing buildings (35 percent), using off-site instructional facilities (5 percent), or other approaches (12 percent). 93p.

Profiles a "green" modular classroom in use in Lincoln, Massachusetts, featuring daylighting, automated dimmers, high-efficiency HVAC, air and vapor barriers, and low-VOC interior products. 3p.

Briefly describes Arizona's Shonto Preparatory School, a small modular high school that serves Navajo students in the north central part of the state. The design process included guidance from a Navajo Architect practicing neo-traditional native American architecture to create culturally significant design elements throughout the building interior and exterior. 2p.

In the wake of Hurricane Katrina, the Federal Emergency Management Agency (FEMA) tasked the Army Corps of Engineers (the Corps) to purchase temporary classrooms for Mississippi schools. To accomplish its task, the Corps placed a $39.5 million order for the purchase and delivery of 450 such classrooms. GAO received an allegation on its Fraud Hotline that the Corps paid inflated prices for the classrooms, and in response, this report reviews the facts and circumstances related to the Corps' issuance of the order. The Corps had no prior experience, no advance notice, and the need to buy the classrooms as quickly as possible. Corps contracting officials lacked knowledge of the industry and information about classroom suppliers, inventories, and prices that would have been useful in negotiating a good deal. Faced with these circumstances, they chose to purchase the classrooms by placing an order, noncompetitively, on an existing agreement with a vendor certified under the Small Business Administrations Business Development Program. The Corps accepted the vendor's proposed price of $39.5 million although it had information that the cost for the classrooms was significantly less than what the vendor was charging. Based on analysis of a quote obtained by the vendor from a local Mississippi business, the price that the vendor actually paid for the classrooms, and prices for similar units from GSA schedule contracts, it was determined that the Corps could have, but failed to, negotiate a lower price. 17p.

The results of a design competition for a re-locatable classroom unit are provided in a slide show with 57 photographs of winning entries. The competition was open to K-12 teams, emerging green builders, and architects and manufacturers. The design teams were required to develop a prototype for a prefabricated classroom unit that makes the learning cottage "the cool place to be" for students, staff and after hours community use. The design needed to reflect a committment to environmental stewardship and high performance standards for durability, safety and health. The teams also considered school siting issues, multiple building schemes and a good connection to the landscape or urban fabric. Information on the competition is provided, as well as list of winners and a powerpoint of the awards.

Offers suggestions on how to acquire and maintain an agreeable installation of portable classrooms. These involve timing your acquisitions for best price, communicating your expectations clearly, selecting a suitable vendor, coordinating the project team, maintaining the units, and communicating with the industry. 8p.

Presents numerous graphs comparing the energy use for a conventional versus a high- performance modular classroom. The total energy consumption of the high-performance unit was 30% less than that of the conventional unit. Figures for HVAC, lighting, hot water, and plug load use are broken out as well. Graphs are presented for each month of the year, with special attention to the extreme-temperature months of February and July. Ventilation and carbon dioxide levels are also covered. 18p.

Covers key components of good modular educational building design, including effective interior layout, quality exterior design that does not look like a trailer, flexibility that allows for growth, and relocatability. 1p.

Sets forth the state's minimum requirements to be met by any manufacturer, vendor, and/or contractor supplying a relocatable building for school use. Requirements cover approval of plans by the state, mobility, dimensions, structural design, chassis design and construction, materials, finishes, wiring, plumbing, HVAC, skirting, built-in educational furnishings, plan requirements, contractor and school authority responsibilities, and warranties. Sample framing schematics are included. Requirements were adopted in 1966 by the Mississippi State Board of Education and revised several times. 12p.

In this study, the energy consumption of two relocatable classrooms located on the southern portion of the campus of Chapel Hill High School in Chapel Hill, NC is investigated. One classroom, the control, was specified and purchased by the Chapel Hill-Carrboro City School System. The other is a performance enhanced classroom designed by the Florida Solar Energy Center and purchased by the North Carolina Solar Center. Both classrooms are 24' by 40' modular structures, completely underpinned, and located adjacent to one another for a side by side comparison. The energy consumption and indoor conditions of each classroom are monitored by a data-logging system that also records outdoor conditions via a weather station. The performance enhanced classroom is equipped with a 3 ton, SEER 12 heat pump controlled by a Bard CS2000 unit, six skylights, increased insulation and envelope sealing, a demand control ventilation system with an energy recovery wheel, and a day lighting system controlled by occupancy sensors. The control classroom is equipped with a wall-mounted 10 kW electric furnace/air conditioning system. A programmable thermostat was also installed in the control classroom after two months of data was collected. A building model is prepared using the Energy-10 software package to estimate the impact the various design changes have on the energy consumption of each classroom. [Author's abstract] 54p.

The purpose of this study was to assess environmental conditions in California's portable classrooms. This report describes the sample design, the survey instruments, the data collection process, the data analysis procedures, and the results that show and compare the major characteristics of the populations of eligible public schools as well as portable and traditional classrooms. Results from this survey suggest that there are major issues associated with environmental conditions in California K-12 schools. Environmental factors, complaints, and health symptoms reported by teachers and facility managers are often different between the traditional and portable classrooms. Measured levels of formaldehyde are significantly higher in the portable classrooms. More extensive monitoring and classroom assessment are required. [Authors' abstract]

Specific features of energy-efficient, "healthier," more durable portable classrooms are described. While they may cost more, they have a big payoff in lower utility bills and they offer a healthier, more comfortable classroom for students and staff.

Summarizes comparative energy performance data from side-by-side installations of standard and energy-efficient portable classrooms in New York, North Carolina, and Florida. The monitoring showed that the heating and cooling needs dominated the energy requirements, with lighting accounting for only about 10-15% of total use. The long term energy savings of the energy-efficient models were 34% for New York, 46% for North Carolina, and 81% for Florida. The specifications of the units and nine references are included. 13p.

Reports results of monitoring to develop reasonable energy performance and cost models for high performance relocatable classrooms across California climates. A key objective was to validate simulations for comparison to initial performance projections. The validated model was then used to develop statewide savings projections by modeling base case and high performance relocatable classroom operation in the 16 California climate zones. Includes 15 references. 38p.

The purpose of this study was to conduct a comprehensive study and review of the environmental health conditions in portable classrooms; identify any potentially unhealthy environmental conditions, and their extent; and, in consultation with stakeholders, identify and recommend actions that can be taken to remedy and prevent such unhealthy conditions. The study also included a review of design and construction specifications, ventilation systems, school maintenance practices, indoor air quality, and potential toxic contamination including mold and other biological contaminants. Results and recommendations are detailed. 220p.

The prevalence of prefabricated, portable classrooms (portables, relocatables, RCs) has increased due to class size reduction initiatives and limited resources. Classroom mechanical wall-mount heating, ventilation, and air conditioning (HVAC) systems may function improperly or not be maintained; lower ventilation rates may impact indoor air and environmental quality (IEQ). Materials in portables may off-gas volatile organic compounds (VOCs), including formaldehyde, as a function of age, temperature, and humidity. For a pilot study, public K-12 schools located in or serving target areas within five Los Angeles County communities were identified. In two communities where school districts (SD) consented, 1-3 randomly selected portables, one newer and one older, and one main building control classroom from each participating school were included. Sampling was conducted over a five-day school week in the cooling and heating seasons, or repeated twice in the cooling season. Measurements included passive samplers for VOCs, formaldehyde and acetaldehyde, and air exchange rate (AER) calculation; indoor air temperature and humidity; technician walk-through surveys; an interview questionnaire above HVAC system operation and maintenance (O and M). Measured classroom AER were low, formaldehyde concentrations were below the state indoor air guideline 'target level', and concentrations of most target VOCs were low. O and M questionnaire results suggested insufficient training and communication between custodians and SD offices concerning HVAC systems. Future studies should attempt larger sample sizes and cover larger geographical areas but continue to assess multiple IEQ parameters during occupied hours. Teachers, custodians, and SD staff must be educated on the importance of adequate ventilation with filtered outdoor air. [Author's abstract] 448p.

Collects the recommendations of designers, manufacturers, child development experts, contractors, government personnel, and financing experts on the use of modular construction in early childhood care and education. Indoor and outdoor design enhancements include larger and lower windows, homelike facades, courtyards, child-scaled entry paths, and covered outdoor decking. 32p.

Reports on laboratory and field studies showing that indoor environmental quality impact of volatile organic compound (VOC) emissions are minor when relocatable classrooms are ventilated at or above code-minimum requirements. Assuming code-minimum ventilation rates are maintained, the benefits attributable to the use of alternate, low-VOC interior finish materials in relocatables constructed by the manufacturer associated with this study are small, implying that it is not imperative to use such alternative finishing materials. However, it is essential to avoid materials that can degrade indoor environmental quality, and the results of this study demonstrate that laboratory-based material testing combined with modeling and field validation can help to achieve that aim. 31p.

Presents a prototype modular early childhood facility, featuring the rotation of one modular of a 3-modular unit to break up the repetitive, boxlike nature typical of modulars. The turning of one unit creates new habitable spaces that can used for outdoor learning and as transitional entrance areas. 12p.

"Commercial Modular Construction Magazine" regularly contains articles where the use of modular schools and classrooms is highlighted. This document contains a selection of those articles, including: (1) "Relocatable Classrooms Come of Age" (Michael Roman); (2) "Systems Building" (Laurie Robert); (3) "Realizing Modular's Merits" (Michael Roman); (4) "Toward Cooler, Quieter, Energy-Efficient Portable Classrooms" (Pamela Reynolds); (5) "Modular Construction Delivers NJ Pre-School" (Bill Ulrey); (6) "School District Saves $200,000 with Permanent Modular Construction" (Doug Crawford); (7) "Access Analysis for Two-Story Classrooms" (Tom Shield); and (8) "Replacement Modular Buildings" (Steven Soenksen). 26p.

Asserting that without an adequate acoustical environment, learning activities can be hindered, this paper reviews the literature on classroom acoustics, particularly noise, reverberation, signal-to-noise ratio, task performance, and recommendations for improvement. Through this review, the paper seeks to determine whether portable classrooms provide acoustically adequate environments for learning. 19p.

This report, responding to a Florida legislative request, examines the Palm Beach County School Board's planned purchase of concrete relocatable classrooms. Following are the findings. (1) Concrete units are more expensive than models with metal stud walls; both types meet state building code standards. (2) The district plans to spend $35 million over 5 years to purchase 500 concrete relocatables. (3) The district's purchase price for concrete relocatables is higher than prices for similar units in other districts. Concrete relocatables are more expensive to purchase and move than alternative types of relocatables, but have the appearance of permanent construction and may have a longer life. (4) If the district purchases 500 concrete units as planned, it will spend approximately $12.7 million more for these units over the 5-year period than if it had bought metal stud wall units. In addition, it costs $1,150 more to move a concrete unit to another location than a metal stud unit. (5) The district reasoned that concrete units were more durable and safer. However, the district did not conduct a life-cycle cost analysis prior to its decision. To better justify future relocatable expenditures, the report recommends that the board conduct life cycle cost analyses to compare available relocatables. 8p.

This handbook provides process information on California's relocatable classroom program and contains the application process, information on preparing for delivery of relocatable classroom(s), district responsibilities regarding relocatable classroom(s), and documentation required for reimbursements. It also discusses regulations regarding special circumstances such as building plans and alterations, removal/relocation of state relocatable classrooms, and district purchasing or "buyout" of state relocatable classroom(s). Furniture and equipment regulations conclude the document. 25p.

Reports the preliminary results of a study of four energy-efficient relocatable classrooms, designed and constructed to demonstrate technologies that simultaneously attempt to improve energy efficiency and indoor environmental quality. Two were installed at each of two school districts, and energy use and IEQ parameters were monitored during occupancy. Two (one per school) were finished with materials selected for reduced emissions of toxic and odorous volatile organic compounds (VOCs). Each relocatable had two HVAC systems, alternated weekly, consisting of a standard heat-pump system and an indirect-direct evaporative cooling (IDEC) system with gas-fired hydronic heating. (Includes eleven references.) 6p.

Statistics on Louisiana's use of portable classrooms including total number of portables currently in use, number of buildings by age category, and average costs. 2p.

The ojective of this investigation was to evaluate innovations that would enable modular classroom builders to improve the energy performance of their classrooms, including improved insulation, better windows, daylighting, cross-ventilation, heat recovery, and radiant barriers for cooling dominated climates. The preliminary results discuss the classroom simulation model; preliminary research; building geometry; energy baseline for various climates; comparison of simulation model to measured data; issues associated with ventilation and infiltration; analyzed measures, and results. 12p.

Reports on a laboratory study evaluating emissions of toxic and/or odorous volatile organic compounds (VOCs) used to finish the interiors of new relocatable classrooms. The study implemented a procedure for VOC source reduction by testing and selecting lower-emitting materials as substitutes for standard materials. In total, 17 standard and alternate floor coverings, wall panels and ceiling panels were tested for emissions of VOCs using small scale environmental chambers. Working with a manufacturer of conventional relocatables and two school districts, specifications were developed for four new relocatables predominantly finished with standard materials. Alternate carpet systems, an alternate wall panel covering and an alternate ceiling panel were selected for the two other relocatables based on the results of the laboratory study and considerations of cost and anticipated performance and maintenance. 36p.

Presents findings and recommendations regarding energy efficiency in portable classrooms. The research used newly built and retrofitted energy-efficient portable classrooms, along with an existing control. The findings describe typical points of air leakage and heat loss, inadequate or incorrectly timed controls, and poorly designed fenestration and ventilation. The costs for retrofitting older portables was deemed reasonable and considerably less than the cost of a new classroom. Practical recommendations for retrofitting existing and specifying in new portables are included. 25p.

Brief outline of costs associated with the procurement and set-up of portable classrooms. The example is from a Georgia school district. This compares the cost per square foot of building a 900 square foot classroom to the cost of purchasing a new trailer. 2p.

Findings are presented from a 2-year experiment exploring ways to reduce energy costs and improve the learning environment in Florida's 25,000 portable classrooms. Improvements were made in two highly instrumented portable classrooms in the following areas: installation of a T8 lighting system with electronic ballasts; a high efficiency heat pump with enthalpy recovery ventilation (ERV); a metal white reflective roof system; and an occupancy based control system for lighting and air conditioning. Findings reveal the lighting system and occupancy control reduced lighting energy use by an average of 53 percent from one year to the next. The ERV provided five times the ventilation air found in the initial configuration, while still controlling indoor humidity to an acceptable level; this significantly cut internal CO2 levels with a potential beneficial impact on indoor air quality. Total reduction in space conditioning energy needs was 39 percent or about 6.9 kWh/day. The project demonstrates the feasibility of altering new portable classrooms in Florida so that they use 40 percent less electricity. Energy savings greater than 30 percent were demonstrated for existing portable classrooms through automated controls and simple changes to the lighting system. 19p.

Parents of children in the Saugus Union School District in California were concerned about the safety of classrooms, particularly portable classrooms. Their concerns were amplified by assertions of a local medical toxicologist following evaluations of some teachers and students, and by an Environmental Working Group report about alleged problems with portables throughout California. Efforts by the school district, environmental consultants, and Los Angeles County health authorities were not sufficiently reassuring to some parents. This report discusses results from an evaluation of the classrooms by the Environmental Health Investigations Branch (EHIB) of the California Department of Health Services. Findings indicated no elevated health risks to students. The report's first part details evaluation methods and findings, while the second part directly answers each of the questions posed to EHIB staff at a parent meeting. Data tables provide results of environmental sampling at each school. (Consultations with outside authorities are appended. Contains 68 references.) 70p.

A California report examines the air pollution risk levels in the State's portable school facilities, the State's response, and recommendations for protecting children's and teacher's health in these types of classrooms. The report reveals that over two million California students spend the school day in buildings that may be harmful to their health. It states that some portable classrooms can expose children to toxic chemicals at levels that pose an unacceptable risk of cancer or other serious illness, but that California has no indoor air health standards for most toxins found in types of buildings and has has failed to exercise effective oversight over air quality. What types of pollution health risks exist in portable classrooms are detailed, particularly risks from formaldehyde and carbon dioxide. Additionally reported are the unintended consequences of the State's push for the use of portables to address student population increases. (Contains 59 references.) 37p.

Many California school districts, in complying with the Class Size Reduction Program, will obtain relocatable classrooms directly from manufacturers who are under no specific guidelines or codes relative to indoor air quality (IAQ). This document, designed to aid school facility managers in minimizing potential IAQ problems, summarizes the indoor environmental quality (IEQ) considerations regarding the purchase/lease of relocatable classrooms and the contracting for renovation of existing space. The key IEQ concerns and preventive measures are provided for relocatable classroom design, construction/installation and first-use, and maintenance. Some issues apply to both relocatable and renovated classrooms. Resource information providing further technical details is provided. 5p.

This report evaluates the current status and critical needs of California schools' facilities with respect to indoor environmental quality (IEQ). It presents a review of available information and a set of recommendations and proposals. Contains a section on portable (relocatable) classrooms.

The Florida Department of Education is monitoring the energy use of two adjacent portable classrooms to compare their energy efficiency in a hot and humid climate and determine if they can be made more energy efficient either by retrofit or when the portables were constructed. This report provides the background of this research and describes the portable classroom's lighting, roofing, heating, ventilation, and air conditioning systems; and discusses results and conclusions. 8p.

Summary and findings of a Florida Center for Community Design and Research report, published in November 1993, investigating the use of portable classrooms as a cost efficient and educationally effective means of handling the on-going short fall of permanent facilities.

This report explores the current role of portable classrooms in California schools and the options available for their use. It examines how widespread portables are, and estimates that more than 86,500 were in use in 1997-1998, a significant increase over previous years, which is partly attributable to the state's classroom reduction plan in grades K-3. The different types of portables being used vary widely, but all of the models must be approved either by the Department of State Architect (DSA) or built under the regulations of the Department of Housing. The construction process for DSA portables is described, along with the practice called "piggybacking," in which several school districts purchase portables together. Some of the issues related to the use of portables include abuses of DSA regulations, elevated maintenance costs, and proper maintenance. Outlines some considerations of the role that portables should play in the increased need for classroom space. Also presents a chart that compares permanent constructions with portable classrooms. 10p.

BCTF Research designed and mailed out questionnaires to teachers working in portables in seven school districts. These districts were selected as districts with a high number of portables, and were also representative of the diversity of school districts. Discusses access issues, quality of heating, lighting, and furniture, poor ventilation/air quality, differences between teaching in a portable and the main building, and security issues.

This paper describes a study that would enable modular builders to improve the energy performance of their classrooms without increasing their first cost. The Modern Building Systems' classroom building conforms to the stringent Oregon and Washington energy codes, and, at $18 per square foot, it is at the low end of the cost range for modular classrooms. The study investigated daylighting, cross-ventilation, solar preheat of ventilation air, and thermal storage as ways to reduce energy use. 7p.

This study examines the current use of manufactured relocatable (portable) classrooms in the public school districts of Florida to determine whether their use is a cost efficient and educationally effective and safe means of handling short-term accommodation needs. Areas of research include: economic impacts; the physical classroom environment; facility planning; construction methodology; and impacts on existing facilities. The study contains questionnaire data received from 57 school districts and 900 teachers; 23 relocatable site visits throughout Florida; manufacturing site visits; and results from meetings with principles, teachers, contractors, and industry representatives. The study concludes with answers to the questions posed in the RFA from the Florida Department of Education Office of Educational Facilities along with recommendations concerning the design and planning of future relocatable classroom facilities. 232p.

Provides guidance to local school districts to assist them in determining the feasibility of relocatable classroom units for their school needs and to set forth certain minimum mandatory construction, safety, and utility requirements that must be complied with by any manufacturer, vendor and/or contractor supplying a relocatable classroom unit for use in the South Carolina public schools. The document's requirements and specifications are organized under CSI MasterFormat categories. 39p.

Describes India's Central Building Research Institute program of partial prefabrication of school buildings in the state of Uttar Pradesh. The program provides the elements of a basic shelter--foundations, supporting columns and a roof--in places where primary schools are needed. The local community is to provide the wall panels, windows, doors, and floor, using local materials and at its own expense. The criteria for the design of the prefabricated elements included 1)simplicity in assembly, 2) ease of transport using lorries or bullock carts, and 3) weight low enough to permit easy handling. This case study details the school designs and the development of the organizational structure to meet the total building program for 5,000 or more schools in a period of three years. 68p.

Reviews recent progress in modular building that has helped it gain a larger share of the construction market in recent years. Features and benefits of current, sophisticated modular construction are covered. Advantages to school systems include quicker construction, less site disturbance, and controlled building techniques that may yield a building with lower environmental impact.

Describes recent LEED-certifiable modular classroom units that are highly energy efficient and feature the use of environmentally sensitive building materials, daylighting, cool roofs, occupancy sensors, and other high performance building features.

Reviews the creation of this reservation school, featuring culturally significant design elements derived from trips through the surrounding landscape, and then incorporated into a cost-saving modular construction.

Charlotte-Mecklenburg Schools (CMS) is ready to test an economical, easy-to-build design that was spawned by a hurricane. ‘Learning Cottages’ could replace mobiles or serve as new construction.

Profiles the custom prefabricated construction of the two-classroom Montessori Children's Center in San Francisco The spatial programming and design ideas respond to the curriculum by emphasizing the connection to nature and the distinction between indoors and outdoor. Plans, photographs, and a list of project participants are included.

During the past three years, commercial modular manufacturers have seen a growing percentage of their modular production targeting the education market. Relocatable classrooms (and, more recently, modular classrooms) account for almost half (46%) of all commercial modular business, with $1.63 billion in annual sales. This discusses what is driving this trend: class size reduction initiatives; growing student populations; increasing costs per square foot of site-built school construction; and growth of the overall educational construction market.

Describes some measures that school districts take when enrollment rapidly outgrows available teaching space, often made even more difficult when districts operate under mandates to reduce classroom size. Emergency conversion of non-teaching space into classrooms, aggressive new building and renovation programs, and portables are discussed, as are proper communication between facilities staff and those who make enrollment projections.

Case study of the Brandlehow Primary School classroom extension in Putney, which opened in January 2006. It is only the UK's second education project to use the prefabricated, wood FinnForest Merk system from Germany, which enabled the addition to be built in a matter of weeks. The new Brandlehow addition consists of a wood building linked by a glazed corridor to the existing building. The FinnForest Merk solid wood walls are highly insulated and clad with cedar boarding.

Describes the virtues of permanent modular school construction, including speed of construction, lower costs, and less disruption at the site.

Describes a "green" modular classroom that is not delivered in halves, but as a single unit with movable walls.

Describes this San Francicso design company's efforts to produce attractive, high performance modular classrooms as an alternative to trailers. Two of the firms models are described, featuring good acoustics, daylighting, and flexibile configuration.

Describes multiplex modular classroom configurations that provide higher quality accommodation than trailers. Installation advice for temporary multiplex modular facilities is included, accompanied by descriptions of successful examples.

Presents an interview with Anja S. Caldwell that discusses the green portable classroom design competition that she initiated, features of the Montgomery County, Maryland, green schools initiative, and advice to other officials on committing to sustainable building programs in their districts.

Reviews the current use of portable classrooms in the United States while describing improvements in their energy efficiency, offering suggestions for maintaining good indoor air quality in them, and recommending active maintenance with timely replacement of units.

Cites the improved energy efficiency of today's portable classrooms while recommending material and landscaping solutions to ensure good indoor air quality and prevent water intrusion that can cause mold. Also recommended are HVAC systems that are quieter and energy efficient, and timely retirement of worn-out portable classrooms.

Discusses temporary and permanent modular construction, citing their differences and describing precast modular construction in particular.

With 118 public school sites in San Francisco, Mayor Gavin Newsom is hoping a sustainable classroom prototype, known as "Project FROG," will provide an improved way to accommodate schoolchildren who are currently housed on campuses in trailers, some of which are poorly insulated and leak.

Describes portable classrooms being installed at the Country School of Valley Village, California, that are designed to be attractive and healthy, with high ceilings, abundant daylighting, sustainable and nontoxic materials, and adequate ventilation.

Describes the Wake County Public School Systems steps to address rapid growth in their school population, including modular campuses, ninth grade centers, adaptive reuse of commercial structures, and a year-round calendar.

Profiles Albuquerque Public Schools' use of portables, including the evolution of construction types, costs, aesthetic concerns, perceptions of their occupants as "second class" school citizens, problems with lighting and water supply, appreciation of individual HVAC control, and landscaping. Includes one reference.

Outlines recovery goals and strategies for areas affected by Hurricane Katrina, emphasizing a multiregional plan that includes coordinated multicounty oversight of construction, creation of joint-use facilities and cross-curricular K-12 schools with flexible design for future conversion, modular buildings, continual communication with the public, re-usable design prototypes and systems construction, design improvements for stronger storm resistance, and use of available commercial facilities for educational purposes.

Describes South London's Lavender Sure Start and Children's Centre, which employs wood-cladded prefabricated construction to create a sensitive children's environment. Photographs, plans, and a list of project participants are included.

Details 13 general, interior, and exterior conditions that should be met in order to have modular or portable classrooms accepted by the students, teachers, and neighbors. Includes six references.

Explains the benefits of precast concrete in school construction, citing short- and long- term savings, speed of fabrication and assembly, plasticity, and choices in exterior finishes that include real or emulated stone and brick.

Compares differences in attitude, behavior, and achievement of students housed in portable versus permanent classrooms. Fifth grade students in 21 portable and 38 permanent classrooms were studied, with the results showing significantly more positive attitude for those students in permanent classrooms. No significant difference was found in student behavior and achievement, however. Includes 27 references.

Reports on an investigation of design improvement for a water source heat pump where the water was stored in flexible plastic bladders resting on the ground beneath modular classrooms. The design improvements replaced the bladders with heat exchangers constructed of PVC pipe. Design, costs, and assembly procedures for the PVC heat exchanger are presented.

Article discusses rethinking transportable classrooms to turn them into truly dynamic learning environments.

Profiles a modular classroom design that is airy, flexible, attractive, and suitable for K- 12 or higher education. The system involves a "sled" that houses mechanical, electrical, and telecommunications systems, a "shed" that sits on top of that and houses the classroom area, and a "power pack" affixed to the end that can house operating equipment, a restroom, office, or laboratory.

The prevalence of prefabricated, portable classrooms (portables) for United States public schools has increased; in California, approximately one of three students learn inside portables. Limited research has been conducted on indoor air and environmental quality in American schools, and almost none in portables. Available reports and conference proceedings suggest problems from insufficient ventilation due to poor design, operation, and/or maintenance of heating, ventilation and air conditioning (HVAC) systems; most portables have one mechanical, wall-mounted HVAC system. A pilot assessment was conducted in Los Angeles County, including measurements of integrated ventilation rates based on a perfluorocarbon tracer gas technique and continuous monitoring of temperature and relative humidity. Measured ventilation rates were low. Compared with relevant standards, results suggested adequate ventilation and associated conditioning of indoor air for occupant comfort were not always provided to these classrooms. Adequate ventilation has the potential to mitigate concentrations of chemical pollutants, particles, carbon dioxide, and odors in portable and traditional classrooms, which should lead to a reduction in reported health outcomes, e.g., symptoms of 'sick building syndrome', allergies, asthma. Investigations of school indoor air and environmental quality should include continuous temperature and relative humidity data with inexpensive instrumentation as indicators of thermal comfort, and techniques to measure ventilation rates. [Authors' abstract]

Describes Florida's use of modular construction, instead of portables, to create classroom space quickly. The trend away from portables was initiated by 1997 state legislation for classroom accessibility, wind resistance, and technology connectivity. Later legislation requiring smaller class sizes, the elimination of older portables, and the overall reduction of portables by half combined to necessitate a method of quick building. The costs, designs, furnishings, and popularity of the modular facilities are detailed.

Presents eight methods for ventilation control in modular classrooms.

Discusses proper HVAC for relocatable classrooms.

Case study of Houston's Robert Browning Elementary's new temporary modular building, erected on tricky triangular site and featuring an unusual exterior and courtyard. This project demonstrates how thoughtful design can enhance a low-budget project.

Describes the use of modular construction by Seattle Pacific University and Seattle Girls School. Both institutions opted for modular construction to accommodate their restrictive budgets, small sites, and the need to minimize disruption on the campus.

Describes a permanent modular addition to the Mathematics, Civics and Sciences Charter School of Philadelphia, which was built in six months, including sixteen weeks of factory construction. The addition maintains the architectural integrity of the existing building and of the downtown Philadelphia site.

The San Juan Unified School District outside Sacramento is stripping its aging inventory of portable classrooms and retrofitting them with better floors and walls and lighting and windows, making them permanent and saving thousands of dollars per unit in the process.

Describes potential indoor air pollutants in portable classrooms, distinguishing between substances likely found in new versus old units. Offers advice to parents of children suspected of being sickened by portable classroom indoor air.

This article explores why the Environmental Health Conditions in California’s Portable Classrooms study, released in 2003, was conducted and what the results mean with regard to the heating, cooling, and ventilation of classrooms.

This article is based on a Lawrence Berkeley National Lab report. The study involves CO2 measurements inside and outside the 436 classrooms of 22 schools in Washington and Idaho. According to the authors, "In this study, 1,000 [parts-per-million] increases in the difference between indoor and outdoor CO2 concentration were associated with 10 percent to 20 percent relative increases in student absence, and the associations were statistically significant. This study confirms previous findings of high CO2 concentrations in classrooms, which indicated classroom ventilation rates were often below the minimum rates specified in codes." [Authors' abstract]

This discusses the growing need for portables because of increasing enrollments, intra-district shifts, the push for earlier education for children, continuing education for adults, lower student-teacher ratios, aging facilities, and tightening budgets. Private schools and charter schools are also seeking faster, lower-cost options. Modulars are built to specific building codes, require miminum maintenance, last for decades, and can be designed to withstand heavy wind and snow loads and unique site conditions.

This supplement presents three articles on modular construction that look at: "Fast Track Expansion for a New Jersey School" (involving a modular addition); "Precast Construction Helps Schools Meet Attendance Boom" (precast concrete components are quick, durable, and flexible); and "Airing HVAC Concerns" (poor indoor air quality in prefabricated portable and relocatable classrooms).

Describes issues related to the use of modular (relocatable) classroom facilities. The Modular Building Institute provides information on modular buildings.