This document discusses frameworks for designing sustainable schools in the US and internationally. It summarizes the Passivhaus standard, which aims for ultra-low energy buildings through superinsulation, airtight construction, and passive solar design. While there is only one Passivhaus school in the US, several have been built in the UK. The document considers whether the Passivhaus standard could work for schools in Iowa's climate, and discusses case studies of existing schools in Iowa. It concludes that developing guidelines and evaluations of existing Iowa schools is needed to help envision the future of sustainable school architecture and education.

1. New School: Building an
architecture for sustainable
living ?
IOWA ACADEMY OF SCIENCE 126th ANNUAL MEETING,
Fort Dodge, Iowa
April 11 – 12th 2014
Dr.AndreaWheeler, Naghmeh Pak, and Megan Fowler
Iowa State University, Department of Architecture

2. NSF EPSCoR Start-Up Grant: “Iowa’s New
School Buildings: A Future Invested in
Sustainability?”
• This paper is supported by funds ($12,000) awarded to the authors as
part of the NSF EPSCoR Energy Utilization Platform Building
Science Plank for ProfessorAndreaWheeler’s project entitled:
“Iowa’s New School Buildings:A Future Invested in
Sustainability?”
• Objectives of the project:
– To identify key concerns and strategies within the US context for the design of
contemporary sustainable schools, comparing with schools in an international
context.
– To develop a program and methodology for a post-occupancy assessment of
Iowa schools addressing both energy performance and occupant behavior.

3. Sustainability in the US
• European perspective: From the perspective of Europe, the US has
been slow to address its carbon emissions.
• Worldwatch Institute report assesses US sustainability:
– US consumes around 207% of its ecological capacity
– Criticized for minimal support for global environmental institutions and
treaties
– Poor performance in mitigating air pollution and water and ecosystem stresses
– 2010 National Geographic survey of 17 developed and developing
countries - Americans ranked worst in green consumption habits

4. The President’s Climate Action Plan
• However, on June 25, 2013, President Obama announced a plan to
reduce carbon emissions, increase the use of clean energy sources,
and mitigate the effects of climate change.At Georgetown University,
he stated:
• “… the world still looks toAmerica to lead […] I am convinced this is
the fightAmerica can, and will, lead in the 21st century. […] We’ll
need scientists to design new fuels, and we’ll need farmers to grow
new fuels. We’ll need engineers to devise new technologies, and
we’ll need businesses to make and sell those technologies. We’ll need
workers to operate assembly lines that hum with high-tech, zero-
carbon components, but we’ll also need builders to hammer into
place the foundations for a new clean energy era” (Obama,TheWhite
House, Office of the Press Secretary, 2013).

5. Schools represent the test for a question
about design and encouraging sustainable
lifestyles
• To develop a method for assessing green schools we need to understand the existing
frameworks for assessment and best practice guidelines.
• We also recognize, Joo Hwa Bay states:“Human behavior and habits can enhance or
frustrate environmental sustainability efforts in the reduction of carbon footprint,
indoor air quality, emissions, and impact to the natural environment” (Bay, 2010,
190).
• Without building user communities educated about sustainability, buildings risk
being poorly utilized and innovative energy technologies misunderstood.
• Moreover, as Lucas argues:“…environmental behaviours [sic] will require complex
and innovative policies and practical interventions across a wide range of different
sectors and at every level of society (i.e. individual, household, community,
organisational [sic], institutional and across whole systems).” (Lucas et al, 2008,
456).

6. Different Frameworks for Sustainable
Schools in U.S.
• CEFPI (The Council of Educational Facilities
Planners International)
• LEED for schools (Leadership in Energy and
Environmental Design)
• ENERGY STAR
• CHPS (Collaborative High Performance
School)
• AASHE (Association for the Advancement of
Sustainability in Higher Education)
• Passivhaus

7. ENERGY STAR
• The analysis for K-12 schools is based on data from the Department
of Energy, Energy InformationAdministration’s 2003 Commercial
Building Energy Consumption Survey (CBECS).
• The analysis includes adjustments for:
• Building Size
• Whether or not the School is Open onWeekends
• Whether or not there is Energy Used for Cooking
• Whether or not the school is a High School
• Weather and Climate (using Heating and Cooling Degree Days, retrieved based
on Zip code)
• Percent of the Building that is Heated and Cooled
• …

8. LEED for Schools
• 79 possible points in 6 sub-categories:
– Sustainable Sites
– Water Efficiency
– Energy &Atmosphere
– Materials & Resources
– Indoor Environmental Quality
– Innovation & Design Process

9. Collaborative High Performance School
(CHPS manuals)
• The Collaborative for High Performance Schools (CHPS) is leading a
national movement to improve student performance and the entire
educational experience by building the best possible schools.
• No Iowan manuals, not even in Illinois

10. Technical performance (in terms of
categories of performance CHPS)
• Similar sub-categories compered to LEED :
– General conditions
– Site planning
– Interior Surface and furnishing
– Lighting and daylighting
– Building Enclosure and insulation
– HVAC
– Other Equipment and systems

11. The Passivhaus Standard
• Passivhaus Institut began in Darmstadt, Germany in 1996
• Independent research institute, voluntary performance-based
standard of energy efficiency in buildings
• Passivhaus buildings require little mechanical heating/cooling
• Integrated design process:
– Passive solar design and landscaping
– Superinsulation and airtightness
– Advanced window technology and natural ventilation
– Internal space heating
– Low-energy lighting and electrical appliances
• Tens of thousands of Passivhaus certified projects in Europe,
residential and commercial
• 78 certified Passivhaus buildings in the US, mostly single-family
homes

12. What is the Passivhaus Standard?
• Basic principles:
– Good insulation with minimal thermal bridges
– Passive solar and internal heat sources
– Excellent level of airtightness
– Good indoor air quality – mechanical ventilation with efficient heat recovery
• No specific requirements for hot water, lighting, and appliance
consumption
– An overall limit on “Primary Energy” consumption encourages energy
efficiency in all of these areas

13. What is the Passivhaus Standard?
Design Component Limiting value
Walls, Roof, Floor (U-values)* ≤0.15 (W/m
2
K)
Glazing unit ≤0.8 (W/m
2
K)
Installed glazing ≤0.85 (W/m
2
K)
Doors ≤0.8 (W/m
2
K)
Infiltration (ach
-1
) ≤0.6 @ n50
Thermal bridging (linear ψ
value)
≤0.01 (W/mK)
MVHR coefficient (η HR) ≥0.75
Ventilation electric limit 0.45Wh/m
3
Appliances High efficiency recommended
Lighting High efficiency recommended
On site renewables No requirement but SHW
typical
Energy performance targets and air
changes per hour
Specific Heating
Demand
≤ 15 kWh/m
2
. yr
Specific Cooling
Demand
≤ 15 kWh/m
2
. yr
Specific Heating Load ≤ 10W/m
2
Specific Primary
Energy Demand
≤ 120 kWh/m
2
.Yr
Air Changes Per Hour ≤ 0.6 @ n50

14. Passivhaus Standard for Schools?
1. Each modern school should have controlled ventilation which meets the criteria for
acceptable indoor air quality.
2. The air flow rates of the school's ventilation system should be based on health and educational
objectives and not on the upper limits of the comfort criteria.The result is: CO2 limit values between
1200 and 1500 ppm and designed air flow rates between 15 and 20 m³/person/h (possibly more for a
higher average age of the pupils).
3. In the interest of justifiable operational costs, the ventilation systems in schools must be operated
periodically or according to demand.
4. Designed so that it is also possible to heat up the rooms to a comfortable level in the morning.
5. The building envelope and heat recovery are designed so that the annual heating demand according is
less than or equal to 15 kWh/(m²a) (based on the total net useable area).
6. Secondary conditions: a) In order to avoid temperature asymmetry, a window U–value of less than or
equal to 0.85W/(m²K). b)The building envelope must be built in a very airtight way. n50 < 0.6 h-1 is
required and < 0.3 is recommended.
7. The annual primary energy demand for all non-renewable energy supplied to the school building
should be less than or equal to 120 kWh/(m²a) (based on the total net useable area).
8. In order to ensure comfort in summer in a Passive House school, the frequency of temperatures over
25°C should be limited to less than 10% of the hours of use.
9. The total effective area-specific heat capacity of the space-enclosing components should be >150
Wh/(m²K) { 540 kJ/(m²K) } (based on the base area of the classroom).Alternatively, additional
cooling facilities must be provided (besides night-time ventilation and shading).

15. Passivhaus Schools – UK (Architype)
• Bushbury Hill Passivhaus School (2011)
– Comfortable environment without expensive energy-saving add-ons
– Built within existing budget and timeline
• Oakmeadow Passivhaus Primary School (2011)
– Also within existing budget and timeline
– Close collaboration with client and fully integrated design team
• Swillington Passivhaus Primary School (2011)
– Replaced an existing 1970s building, includes a nursery, community facilities, a
new parking lot, and landscaping
• Wilkinson Passivhaus School (2013)
– Replaced a school destroyed by a fire in 2010
– Local authority insisted on Passivhaus design

18. Center for Energy Efficient Design (CEED) in Franklin County,Virginia
US Comparison - Passivhaus School – only one in the US

19. Center for Energy Efficient Design (CEED)
• Envisioned as a tool for learning, open to surrounding
communities
• 70% energy savings by using Passivhaus standards
• Challenges with US expectations of comfort
• Equipment and products needed to be specially created while
widely available in Europe
• Building today manufactures more energy than it uses
• The project team hopes its success educates and encourages
more Passivhaus schools in the US
– The more common Passivhaus becomes, the easier it will be to implement

20. Passivhaus in Different Climates
• Initially developed for mid to northern European climates, but can
work extremely well for hot, humid climates as well
– Airtightness and insulation work equally well in protecting buildings from
overheating, provided shading is adequate
• Mechanical ventilation can pre-cool supply air and adjust humidity
levels as needed
– Energy RecoveryVentilation may be preferable to Heat RecoveryVentilation to
reduce the humidity load of ventilation on the mechanical system
• Cross-ventilation and night purge strategies may apply
• When a residual cooling load is needed in particularly hot regions, the
Passivhaus standard permits 15 kWh/m2.yr of cooling energy to be
used
– This has proven sufficient in almost all cases due to Passivhaus’ ability to reduce
unwanted heat gains

21. Are Passivhaus standards appropriate for
Iowan schools?
• The climate of Iowa makes strategies like natural ventilation difficult
• There is good opportunity for energy generation – wind, solar
• Insulation and air-tightness are already important for designing in
Iowa.

22. Iowan Schools – Case Studies 1
Ballard High School, Huxley, Iowa
HAILAArchitecture

23. Iowan Schools – Case Studies 2
VanAllen Elementary
North Liberty, Iowa

24. Iowan Schools – Case Studies 3
North Central Junior High
North Liberty, Iowa

25. The future for sustainable architecture? The
future for education?
• No Iowan manuals, no guidelines specific for the climate and culture,
but there is a need for evaluation and post-occupancy assessments of
schools in Iowa.
• Education for sustainability and the problem of building an
environment and community for sustainable lifestyles to emerge
underpins this work.
• Passivhaus schools to be studied in the UK over the summer.
• After an evaluation of the different frameworks for envisioning what
constitutes a sustainable school – what qualities of the environment
may be absent - and whether frameworks are flexible enough for a
variety of US environments and cultural contexts – the development of
a program of post occupancy evaluation of schools and the outline for
our own framework will be the focus of our work.