2.1 COMPARISON OF TWO PASSIVE HOUSE SCHOOLS IN NORWAY AND GERMANY

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1 2.1 COMPARISON OF TWO PASSIVE HOUSE SCHOOLS IN NORWAY AND GERMANY ABSTRACT Antje Junghans Norwegian University of Science and Technology (NTNU) Thomas Berker Norwegian University of Science and Technology (NTNU) Purpose: The purpose of the paper is to explore the management and use of highly energyefficient public buildings, with special focus on passive house school buildings. The paper addresses public building owners as well as facilities managers as innovators and early adopters of technology and management solutions for future buildings. Background (State of the Art): An overview of the state of the art in passive house school building development is presented and studied in detail, with a focus on comparative case studies of the first passive house school buildings finished and taken into use in Germany and Norway. Approach (Theory/Methodology): The passive house standard and its application for school buildings were defined on the basis of literature research. Germany was identified as one of the first countries to adopt passive house standard to public school buildings. By using German, Norwegian, and English keywords, 70 examples of built passive house schools were identified. Two were selected for in-depth study as they are well documented and have been studied by other researchers: Riedberg School, one of Germany s first passive house schools and taken into use in 2004; and Marienlyst School in Norway, which was finished in A comparative analysis was conducted to highlight the similarities and differences between the two schools, and in order to discuss the impact of high energy-efficient building technology on public facilities management and user behaviour. Results and Practical Implications: The paper provides an overview of the state of the art in built and used highly energy-efficient school buildings, and addresses challenges and innovative solutions for facilities management and user behaviour. Originality/value: The paper contributes to a better understanding of passive house buildings and the challenges related to facilities management and user behaviour. Keywords: Energy efficient public buildings, Energy management, Facilities Management, Passive house school, User behaviour 47

2 1 INTRODUCTION Passive house schools are highly energy-efficient public buildings. In Europe according to climate and energy policies and a package of binding legislation, the numbers of such buildings are expected to increase in near future. The EU s strategy defines three targets for an integrated approach to climate and energy policies until 2020: a 20% reduction in EU greenhouse gas emissions from 1990 levels; raising the share of EU energy consumption produced from renewable resources to 20%; and a 20% improvement in the EU s energy efficiency (European Commission, 2007). The Energy Performance of Buildings Directive (EPBD) promotes the development of almost zero-energy buildings: By 31 December 2020, all new buildings shall be nearly zero-energy consumption buildings. New buildings occupied and owned by public authorities shall comply with the same criteria by 31 December 2018 (EPBD, 2010). This directive also encourages the introduction of intelligent metering systems for monitoring energy consumption whenever a building is constructed or undergoes renovation. The following research questions regarding the management and use of passive house schools are addressed in this paper: 1. What impact does the development and implementation of highly energy-efficient buildings and technical infrastructures have on day-to-day energy management and user comfort? 2. What are the benefits and risks of passive house schools from a facilities management and user perspective? 3. What are the similarities and differences between passive house schools in Norway and Germany, which are countries with different climatic conditions? 2 STATE OF THE ART In Germany the term Passivhaus (English: passive house, Norwegian: passivhus) was launched by the Passive House Institute (Passivhaus Institut, PHI), an independent research institute. Since the 1990s, the institute has contributed to the development of the passive house concept. The first inhabited pilot project was a multifamily house in Darmstadt with heating energy consumption below 12 kwh per m 2 per annum (PHI, 2012a) The PHI defines the passive house standard as energy efficient, comfortable, and affordable. Energy consumption for heating is less than 15 kwh/m 2 /p.a. Passive houses use solar energy, internal heat sources, and heat recovery. During the warmer months of the year, passive cooling is achieved through strategic shading. The thermal comfort of the indoor environment benefits from little variation between the temperatures of internal surfaces and air. Passive houses have highly insulated building envelopes, including the roof, flooring, exterior walls, and special windows. Ventilation systems with heat recovery supply constant fresh air and recirculate the heat contained in the exhaust air (PHI, 2012b). Important benefits of passive house buildings are energy savings between 75 90% compared to existing building stock: the latter have an average annual energy consumption of 200 kwh/m 2 /p.a., whereas passive house schools have less than 23 kwh/m 2 /p.a. Furthermore, the savings should not only be considered in terms of energy consumption, but also in energy costs and environmental impact (Peper et al., 2007; PHI, 2012b). 48

3 The Norwegian Government plans to tighten the energy requirements in the building code to passive house level by 2015 and almost zero-energy level by 2020 (Ministry of the Environment, 2012). A newly developed passive house standard for non-residential buildings in Norway (NS 3701:2012) has specified and developed further the original PHI approach (PHI 2012a; PHI 2012b) according to differing climatic, building construction, and architectural contexts. In Norway, the certification of buildings as conforming to either passive house or low-energy standard includes minimum requirements for: heat losses; cooling demand; heating demand; energy supply, and technical infrastructure as parts of the building, components, and systems, as well as air tightness of building envelope. Passive house criteria defined by the Norwegian standard are applicable to 11 different types of non-residential buildings, including school buildings. The following requirements for the certification of passive house school buildings in Norway have been specified on the basis of a building size of more than 1000 m 2, an annual mean temperature above 6.3 C (in Oslo), and a maximum outdoor temperature of 20 C: 1. The heat losses for transmission and infiltration are not more than 0.40 W/m 2 K 2. The building is designed in a way that thermal comfort is achieved with very low energy demand for cooling of indoor air and/or supply air. The energy supply for cooling is 0 kwh/m 2 /p.a. 3. The heating demand for spaces (romoppvarming) and ventilation (ventilasjonsvarme) is not more than 20 kwh/m 2 /p.a. 4. The passive house must meet requirements for energy supply in accordance with the regulation on technical requirements for construction (building code) 5. The minimum requirements of building parts such as U-values for windows and doors < = 0.80 W/m 2 /K, components, systems, and leakage rate less than 0.60 h -1 are achieved (NS 3701:2012). The management and use phase of buildings facilities management (FM) is defined as: The integration of processes within an organization to maintain and develop the agreed services which support and improve its primary activities (EN , 2007). The passive house school building, including all technical infrastructures, building parts, components, and systems are referred to as the school facility. Energy management is a subdomain of FM, and integrates all relevant facilities services to ensure that Client demand for utilities (technical infrastructure) is satisfied by services resulting in a comfortable climate, lighting/shading, electrical power, water and gas (EN , 2007). The main area of responsibility is visible in the operational and utilization phase of a building. Regular monitoring of the power consumption, benchmark analysis, and identification of savings potential and its implementation are essential working areas in energy management (Junghans 2012). An FM client is a composite group consisting of building owners, users, and end-users at all levels of an organization. Often, the organization as an aggregate is addressed as the user of a building. In this sense, the organization as such has specific demands and resources. However, a building interacts directly with its occupants, and it cannot be presupposed that the organization s demands and resources will coincide with the demands and resources that each of its members has in relation to their daily interactions with the building. Rather, especially in relation to energy consumption, there is a wide array of different ways of using buildings. Studies showing this kind of variety of uses are often conducted in relation to residential buildings (e.g. Wilk & Wilhite 1987; Aune 2007), but there are clear indications that similar processes are in operation at workplaces (Berker 2011; Heerwagen & Diamond 1992). The 49

4 heterogeneity of users and the required interaction between user demand and facilities services are the main reasons to add an explicit user perspective to the FM perspective. 3 APPROACH By using German, Norwegian, and English keywords, 70 passive house school projects were identified from publicly accessible sources. The information relating to the projects was then structured according to the following criteria: name of the school, year of completion, country in which the school was located, and sources of further information. The sorting on the basis of country of location revealed the following distribution of passive house schools in Europe: Germany (36 schools), Austria (22), Norway (6), France (2), UK (2), Belgian (1), and Netherlands (1). This geographical distribution in our sample clearly reflects that the passive house standard has its origins in German-speaking countries. The sorting on the basis of year of completion revealed that 46 documented passive house schools were completed between 2009 and 2013, 18 were completed between 2005 and 2009, 4 were completed before 2005, and 2 were expected to be completed in 2014/15. These results correspond well to the general trend towards an increasing number of passive house buildings in Europe. The oldest, well-documented, passive house school projects were examined more closely because they had been in the operation and use phase for a number of years. Projects in Norway and Germany were selected as examples to describe how the passive house standard is applied in countries with different climatic conditions. The following list was developed for a comparison of the selected schools, and considers criteria of the above-mentioned definitions and the key issues for further development of passive house school building project documentation: 1. Building history, ownership, management, and use 2. Location and climate conditions 3. Architectural design and heated floor area 4. Energy supply and consumption 5. Challenges for management and use. The following analysis is based on secondary analyses of studies conducted in the use phase of the two schools. More specifically we draw on the metrological study and analysis (Peper et al., 2007) for Riedberg School. The main source for Marienlyst school is a quantitative survey (employing the Örebro Questionnaire, N = 340) in conjunction with 23 semistructured interviews with teachers, pupils and facilities managers conducted in 2011 (Thunshelle & Hauge 2012). 4 RESULTS COMPARISON OF MARIENLYST AND RIEDBERG SCHOOL In Norway, the construction of Marienlyst School, a lower secondary in Drammen, was finished in 2010 and the building has been in operation and use since then. Riedberg School, a 50

5 primary school and preschool in Frankfurt am Main, is considered Germany s first passive house school and has been in management and use since its year of completion in Both school projects are well documented and have been considered as highly energy efficient buildings within research and demonstration projects in Norway and Germany (Peper et al., 2007; Dokka & Andersen, 2012). 4.1 Building history, ownership, management, and use Drammen Eiendom KF, the real estate and FM department of Drammen Municipality represents the owner of Marienlyst School and is responsible for the management of the school building. Marienlyst School is one of 21 schools making up the total 300,000 m 2 of public buildings owned by Drammen Municipality. The general field of responsibility of the real estate and FM department includes operation, maintenance, modernization, new building development and realization, purchasing, selling, leasing, and renting. In 2013 the main users of Marienlyst lower secondary school (ungdomsskole) were 510 pupils in the age range years, in 8th to 10th grades. The school had 60 employees. In 2008, the Norwegian architectural firm div.a arkitekter was engaged with the project planning after they had won the first prize in an architectural competition that had five participants. During the competition there were no requirements to meet passive house standards, but the decision to adhere to the standards was made after the construction work on the new school had started. However, the compact body of the building has since proven to be very suitable to meet the stringent energy requirements associated with the passive house standard (Dokka & Andersen, 2012; Hahn, 2013) (Drammen kommune 1 ). The primary school and preschool in Frankfurt am Main Riedberg is well known in Germany as an example of a passive house school. The Passive House Institute was involved in the planning and implementation phase of the school and has since conducted research on behalf of the City of Frankfurt am Main. The planning and construction phase of Riedberg School started with an architectural competition in The school was finished and taken into use in November In 2007 Riedberg School had 400 pupils (in the age group 6 10 years) in 16 classes belonging to 1st to 4th grades. In addition, children, in five groups, attended the preschool (Peper et al. 2007). The school is owned by the city of Frankfurt am Main, represented jointly by the Stadtschulamt (school department) and the Hochbauamt (building construction department). 2 The Stadtschulamt is responsible for the facilities management of the city s schools, whereas the Hochbauamt is responsible for the energy management and maintenance of the buildings. In 2001 the architectural office 4a Architekten, in Stuttgart, won the first prize in an architectural competition, and was engaged to design and plan the construction of Riedberg school 3 (Peper et al. 2007; Bretzke, n.d.). 4.2 Location and climate conditions Marienlyst School is located in the centre of Drammen, 40 km west of Oslo. The school is close to a sports park (Marienlyst idrettspark) and a public swimming pool (Drammensbad) (Hahn 2013). Drammen has an annual mean temperature of 6.3 C. The average temperature 1 (accessed 30 September 2013). 2 (accessed 13 November 2013) ) (accessed 13 November 51

6 in summer is 20 C and in winter it is 1 C. The warmest months are July and August, with the highest temperatures reaching 26 C and the lowest temperatures falling to around 13 C in the evenings. The coldest month is January, with an average temperature of 4.7 C. 4 Riedberg School is situated in Riedberg, a northern suburb of Frankfurt am Main. Frankfurt am Main has an annual mean temperature of 9.7 C and a horizontal irradiation of 1046 kwh/m 2. The typical heating period begins 1st October and ends on 30th April. The average temperatures measured in the heating periods in and were 4.3 C and 8.5 C respectively (Peper et al., 2007). 4.3 Architectural design and heated floor area Marienlyst School is a compact building comprising three stories. Due to natural changes in the ground level on site, the first floor is partially buried and includes a large common room for the whole school, as well as wardrobes, special rooms, and a library. The second floor has a community area with a café, workplaces for teachers, administration offices, and special rooms. The third floor consists mainly of compact student areas and group rooms. The architectural design is characterized by the clear and simple building volume with a lot of variation in architectural expression, form, and use, of materials. The school has a heated floor area of approximately m 2 (div.a arkitekter, 2010; Dokka & Andersen, 2012; Hahn, 2013). Riedberg school building has three stories and is U-shaped in plan. The main users are small children visiting primary school and preschool. In addition, sports facilities are located near the school, on a prominent hillside position. The school has a heated floor area of approximately 5540 m 2 (Peper et al. 2007; Bretzke, n.d.). 4.4 Energy supply and consumption Marienlyst School has been built in accordance with passive house standard requirements. The total energy demand is calculated as 75 kwh/m 2 /p.a. The main energy sources are a district heating system and electricity. The measured net energy demand in the period between 1st July 2011 and 30th June 2012 was 60.9 kwh/m 2 /p.a., including energy consumption for room heating, ventilation heating, domestic hot water, fans and pumps, lightning, and technical equipment (Dokka & Andersen, 2012; Hahn, 2013). In the first year of management and use of Riedberg School, the heating energy consumption was documented by the Passive House Institute as 25.4 kwh/m 2 /p.a. ( ) and in the following year it was 14.5 kwh/m 2 /p.a. ( ). Several reasons for the difference in consumption between the two years were considered: lower occupancy rate, the thermal charge of the ground in the first years after construction, the drying out of the building, and the lack of some optimizations (Peper et al. 2007). The energy consumption certificate (Energieausweis) for the building documents a total net energy consumption of 43,3kWh/m 2 /p.a., which includes an average annual consumption of 29kWh/m 2 /p.a. for heating (including domestic hot water ( ), and 14.3 kwh/m 2 /p.a. for electricity ( )). Wood pellets are used as an energy source for heating and domestic hot water. 5 4 Source: World Weather Online, (accessed 28 September 2013) 5 (accessed 12 October 2013) 52

7 4.5 Challenges for management and use Ensuring a good indoor thermal comfort was described by Geir Andersen, technical director of Drammen Eiendom KF, as one of the main tasks of daily management. Andersen (2010) explained that this task includes controlling the temperature and the ventilation air volumes. Internal heat sources and sunshine can cause overheating, which needs to be avoided. Highly developed technical systems are considered as good solutions to such problems. The challenge is to optimize the demand by controlling the heating, ventilation, and lighting. A first resume from the real estate and FM departments perspective is: Build intelligent buildings and operate them intelligently (Andersen, 2010). There exists compelling evidence that suggests that school buildings architectural features have considerable influence on pupils learning progression (Barrett et al. 2013). In the case of Marienlyst School, a survey conducted among occupants found fewer symptoms related to indoor environmental problems than in an average Norwegian school building (Thunshelle & Hauge 2012). The interviews revealed that especially the pupils felt a certain pride to be part of an environmentally friendly building (Thunshelle & Hauge 2012: 20), a factor which has been reported earlier for residential buildings (Thomsen et al. 2013). While these factors are likely to support learning progression, findings from the same study also support the building manager s impression that the automatic environmental controls could be improved further. In this context, especially temperature control, glare, static electricity, and pressure conditions in the building were mentioned by the building s occupants. The fact that no clear improvements to the problems were reported after two years of occupancy indicates that these problems were not solved by fine-tuning the building s systems. 5 PRACTICAL IMPLICATIONS The results of the studied passive houses can be used as input for further research as well as for public building owners and facilities managers as innovators and early adopters of future buildings technology and management solutions. The similarities and differences between the passive house schools in Norway and Germany are listed in Table 1. In both countries, Norway and Germany, especially the challenges for management and use seem to be more similar than different, and provide possibilities for further research and development cooperation on an international level. 4.1 Building history, ownership, management, and use Year of construction Ownership and management Table 1: Passive house schools in Norway and Germany: similarities and differences Similarities Differences Both school buildings were the result of architectural competition and were designed and planned by winning architects Both schools are pilot projects and electively constructed to passive house standards Both schools are owned and managed by public authorities 53 Decision to build Marienlyst School to passive house standards was made during the construction phase Riedberg School is 6 years older than Marienlyst School Drammen Eiendom KF represents the owner and have responsibility for the management of Marienlyst School, whereas the management of Riedberg School involves more departments in the City of Frankfurt am Main

8 User The schools have a similar number of students and employees Marienlyst School is a lower secondary school; Riedberg School is a primary school with a preschool 4.2 Location and climate conditions Location Heating period Both schools are located in urban environments The heating period in Oslo (18 September 8 May) is three weeks longer than in Frankfurt (1 October 30 April) and the annual mean temperature in Oslo (6.3 C) is lower than Frankfurt (9.7 C) 4.3 Architectural design and heated floor area Building Both school buildings have three stories Marienlyst School has a compact building shape in plan; Riedberg school is U- shaped in plan Heated floor area Marienlyst School has a larger heated floor area (6450 m 2 ) than Riedberg School (5540 m 2 ) 4.4 Energy supply and consumption Energy sources Total net energy demand ( ) 4.5 Challenges for management and use Technical components and systems User behaviour Other issues and/or recommendations Both schools use renewable energy sources Both schools have remarkable low demands for electricity In both schools, room heating is provided in addition to ventilation heating Users in both schools have no responsibility for ensuring a good indoor climate At both schools the passive house standard is considered to provide better learning conditions for students and better working conditions for teachers Marienlyst School uses district heating sources; Riedberg School uses wood pellets as an energy source. The total net energy demand of Marienlyst School (69 kwh/m 2 /p.a.) is higher than that of Riedberg School (43 kwh/m 2 /p.a.) At Marienlyst School the optimization of the demand, controlling for heating, ventilation, and lighting, is considered a challenge. 6 CONCLUSIONS What impact does the development and implementation of highly energy-efficient buildings and technical infrastructures have on the day-to-day energy management and user comfort? A low energy demand for heating has been demonstrated in the studied cases of Riedberg School (Germany) and Marienlyst School (Norway). Efficiency in day-by-day management 54

9 is achieved by additional efforts in design, construction materials, and technical systems to reduce the heat losses and make best possible use of the available, natural, and user-related heat sources. In the case of Marienlyst School, additional intelligent technologies such as demand-controlled ventilation and automatic blinds were implemented, whereas the older Riedberg School relies on room-based controls combined with a central time-based control system. To date, experience from Marienlyst School has shown that the added technological complexity has neither increased user satisfaction nor reduced energy consumption. A common characteristic of both schools is that the additional energy demand for electricity is relatively high and causes total net energy demands of kwh/m 2 /p.a. This finding indicates that possibilities for improvements in passive house standards should be further examined, especially regarding reductions in electricity consumption and the implementation of renewable sources for electric energy provision. Today, improvements focus on the optimization of a building envelope s thermal insulation. Highly energy-efficient insulation and airtightness of a building envelope increases building and maintenance costs and reduces flexibility for adaptation to changing user demand in a long-term perspective. From a day-to-day management perspective, the quality and quantity of changing user demands impact the controlling and monitoring of the technical systems. Highly energyefficient buildings therefore require highly energy-efficient management. This in turn requires high technological standards for building control and monitoring systems, and highly qualified operational and management staff. REFERENCES Andersen, G. (2010), Hyggelig å være her! Passivhusskole utfordringer, available at: %20Drammen%20eiendom%20KF.pdf (accessed 13 November 2013). Aune, M. (2007), Energy comes home, Energy Policy, 35, 11, doi: /j.enpol Barrett, P., Yufan Zhang, Joanne Moffat, and Khairy Kobbacy (2013). A Holistic, Multi- Level Analysis Identifying the Impact of Classroom Design on Pupils Learning. Building and Environment 59 (January 2013): doi: /j.buildenv Berker, T. (2011), Domesticating Spaces. Socio-Technical Studies and the Built Environment. Space and Culture 14 (3). Bretzke, A. (n.d.), Planning and construction of passive solar primary school Kalbacher Höhe 15, Frankfurt am Main, available at: (accessed 6 October 2013). div.a arkitekter (n.d.), marienlyst school Drammen, available at: (accessed 6 October 2013). Dokka, T.H. & Andersen, G. (2012), Marienlyst school Comparison of simulated and measured energy use in a passive house school, Conference Passivhus Norden 2012: From Low Energy buildings to plus energy developments, Trondheim, October, available at: (accessed 17 September 2013). EN (2007) Facility Management Part 1: Terms and Definitions. EPBD (2010), Energy performance of buildings, Directive 2010/31/EU of the European Parliament and of the Council of 19 May 2010, available at: 55

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