Introduction
A shift in the green schools movement has been taking place: from focusing on the spectacular new buildings with innovative high performance features we see profiled in the greater media to a sobering awareness of the much larger number of existing school facilities in critical need of improvement.

In the US, students attend school in some 133,000 existing schools, and each one of those schools faces its own facilities challenges. These schools present the greatest opportunity to affect the most change: it is in these schools where most of our students attend school, where most of the energy is consumed, where the air and acoustic quality is poorest and where the funding is most out of proportion to actual need. The 2009 Report Card for American Infrastructure gives schools a ‘D’ grade, lower than bridges. The National Education Association’s estimate for maintenance improvements alone is $322 billion.

More recently, however, resources are beginning to move from replacement to renovation. Renovation can be less expensive than replacement, and consumes fewer building materials. Existing schools are often located in the heart of their communities and can have historic character or preservation features of particular meaning to the community. Of course, existing buildings pose unique challenges to designers – poor response to climate, energy inefficiency, erratic and illogical ‘improvements’ over the years – much of which can be hidden until exposure during construction.

The CHPS Approach to School Modernizations
Existing buildings can, indeed, get to high performance with the right strategy. From its beginning, the Collaborative for High Performance Schools (CHPS) – a national green schools non-profit - has focused on high performance modernizations. Through its high performance building standard, the CHPS Criteria, CHPS has created strategies and approaches for major modernizations and new additions on existing campuses.

In 2006, the state of California used the CHPS Criteria to form the backbone of the High Performance Incentive (HPI) Grant program, a state-run program that incentivizes high performance building by distributing grant money based on the level of participation in high performance strategies.  The state is revising its funding model to include more funding for modernization projects, including a base incentive grant of $250,000 per school pursuing modernization. These regulations are currently under public review until November 29, 2010.

Twelve states currently have or are pursuing an adaptation of the CHPS Criteria for new construction and major modernizations. This year, CHPS developed a Core Criteria, on which all future CHPS Criteria will be based. The Core Criteria outlines the fundamental strategies that must be part of a new high performance school standard.  Central to the Core Criteria is the modernization approach, which has embraced the best strategies from various states to address existing buildings. In the last year and a half, several new post-occupancy studies of the actual performance of green schools were published. The Core Criteria integrates the lessons gleaned from these experiences.

Lessons from Post Occupancy Studies
Design teams pursuing major modernizations of existing buildings should take note of a recent study on operating performance. In the ‘Massachusetts Green Schools Post Occupancy Study of Energy Efficiency[1]’ the average school used 19% less fuel (that’s good) but the prediction was 31% less. The usual suspects for excessive energy use showed up in many of the studies – plug loads not controlled, using systems needlessly at night and off hours, lack of awareness of actual usage by both maintenance personnel and users, lack of training of system operation, and systems that are hard to operate, not optimized or simply not working correctly.

For major modernizations that include the building envelope as part of their scope, design teams should strongly consider daylighting strategies. Daylighting, correctly designed and easily controlled, is essential for a successful green school. In addition to the well-documented benefits for both learning and working environments, daylighting is core to a holistic energy saving strategy – especially in existing buildings where many design options are limited.

Commissioning, which is included in the major modernization prerequisites for projects that include lighting and HVAC upgrades, may be the single most cost-effective strategy for reducing energy costs and greenhouse gas emissions. This is the conclusion of the world’s largest compilation and analysis of commissioning by Lawrence Berkeley National Laboratory[2]. Surprisingly, the results were even higher in existing buildings (16% saving with 1.1 year payback) than new. Contrary to popular perception, even smaller buildings were cost-effective.

Green buildings do perform better than their conventional counterparts. The studies suggest that the more integrated the approach during design, the greater the likelihood of positive occupant responses and the higher the energy savings. ‘Integrated’ means taking a holistic approach that includes all high performance categories, and includes the users and maintenance and operations staff in the process of design. Major modernization projects have equal opportunity to use integrated design practices, even if the projects touch fewer building systems than in new construction.

The Core Criteria: Strategy – Design – Persistence
The emphasis of the Core Criteria is changing to adoption of an integrated ‘overall vision’ approach to modernization, renovation and system upgrades and, simultaneously, a focus on the performance of the facilities long after the construction has been completed, i.e. – the ‘Persistence’ of the design features and systems.

The credits in the Core Criteria that are available for major modernization projects include a number of credits developed across the US. Under the ‘Strategy’ section the ‘Energy and Maintenance Plan’ credit came from New York, CA-CHPS contained credits for ‘Integrated Design’, and ‘Educational Displays’ that promote the ‘Buildings that Teach’ concept.

The Design Section contains most of the ‘Bricks and Mortar’ credits updated from the previous scorecards. NE-CHPS contributed the “Elimination of CFC Based refrigerants” credit.

Under the new Section ‘Persistence’ we are likely to see commissioning that continues into post occupancy to provide much needed training, real time energy displays that inform both users and maintenance staff of energy use, sub-metering of buildings so that meaningful monitoring can take place, demonstration of the high performance features and why they matter to the world at large, green cleaning to maintain air quality, and green purchasing of furniture and equipment.

Case Study – Loyola Elementary School, Los Altos, CA
In any renovation one of the first steps is to analyze the thinking that was done when the building was built. Different priorities have driven building design, leaving a legacy of buildings that solve problems that we may have forgotten.

Post-World War II suburban development in the United States was fueled by government aided home-buying and freeway construction, making up for years of stagnant growth. Loyola Elementary School, in Los Altos, California, was constructed in 1948 as part of this building boom. Designers employed repetitive mass-production techniques and a highly rational layout of daylit, naturally ventilated classrooms. Loyola met the needs of its community at that time. But by 2002 it had significant wear and tear, and some conceptual problems as well. Educational ideas embraced diversity instead of repetition. In addition, the building was found likely to perform poorly in the event of a moderate earthquake.

Loyola Elementary School – Before

In renovating Loyola, Gelfand Partners Architects took advantage of the sustainable daylighting and ventilation that were intrinsic to its original design. The designers also wanted to stay comfortably within the expressive language of the building and its straightforward functionality, while improving its scale and introducing a more comfortable rhythm. Structural improvements drove changes to the envelope, including new sheathing on the roof and new shear panels in the walls. To rebalance the classroom daylighting scheme, designers included new monitors in the roof to fill in at new shear panels. The monitors coordinated with the location of existing roof framing.

Loyola Elementary School - After

Within the classrooms the changes resulted in great daylighting, natural ventilation, and better acoustics. Another choice the team made was to leave the old window system in place even though it included single pane glazing. This was an economic choice, and also recognized the frequency with which glazing gets broken on school sites. In this mild California climate not a great deal of additional heat is needed once lights, children, and computers heat up the classroom. The designers did upgrade to R-30 insulation in the ceiling. The project is modeled at over 30% better than the California energy code in place at the time. Now, four years after completion, its actual utility bills are closer to 50% below the code-complying elementary school across town. Electric lighting, with daylight compensation and occupancy sensors, rarely runs at greater than 10% capacity in daytime use. Additionally, natural ventilation is created when the energy management system opens a clerestory window instead of running a fan.

[1] http://www.chps.net/massachusetts/MA_POStudy_FINAL_110509.pdf

[2] http://cx.lbl.gov/documents/2009-assessment/LBNL-Cx-Cost-Benefit.pdf

About the Authors
Lisa Gelfand, AIA, LEED AP, is founding and managing principal of Gelfand Partners Architects in San Francisco, and a principal of Roesling Nakamura Terada Architects in San Diego.  At Gelfand Partners, Ms. Gelfand has designed or supervised the design of over 34 education projects, as well as over 2500 units of affordable housing created primarily through the sustainable adaptive reuse of existing or historic buildings. Ms. Gelfand is the principal author of Sustainable School Architecture, Wiley and Sons, 2010, and is currently preparing a second book for Wiley to be titled Sustainable Renovation.

William "Bill" Orr, C.E.G. became the Executive Director of CHPS in July 2009, after working for the state of California for almost thirty years. For a majority of his career in state government, Bill worked for the California Integrated Waste Management Board where he managed their Green Building and Environmentally Preferable Purchasing programs from 2000-2007. On the CHPS Board from 2002 to 2007, Bill was the head of the CHPS Technical Committee from its inception through 2007.  Bill was inducted into the California Green Schools Hall of Fame in 2007 for his pioneering work with CHPS. Bill is a registered Engineering Geologist in California.

Rob Samish, AIA, LEED, is a Senior Associate in the Education Studio at Lionakis, an architectural, engineering and planning firm based in California. Rob has maintained a long-standing involvement in sustainable architecture over his twenty-eight year career in architecture. Rob is on the CHPS Board of Directors, is a member of the High Performance Planning Committee for California's K-12 advocacy organization Coalition for Adequate School Housing (CASH) and also a member of the Council of Educational Facility Planners International (CEFPI).