Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
How to obtain LEED credits with natural ventilation LEED, or Leadership in Energy & Environmental Design, is a green building certification program developed by the U.S. Green Building Council (USGBC) to promote and direct buildings into more sustainable practices. This paper gathers information about LEED certified system and the potential benefits which LEED certified buildings could give regarding productivity, health etc. This is done via existing research literature and its wellknow and well-established findings. WindowMaster’s indoor climate solutions have been put to the test and have been evaluated to see how many LEED points these system could have an influence on. This showed that a proper and well designed natural ventilation system has an influence on up to 22 LEED points out of a total of 110. This is supported by LEED reference cases, which has already being certified. Executive summary This paper provides information about the potential LEED points obtained when using a natural ventilation system as well as benefits of a LEED certified building and lastly case studies supporting the evidence A proper and well-designed natural ventilation system has an influence on Throughout the nine LEED case studies it was found that ▪up to 22 LEED points out of a total of 110. ▪“ The research told us that 45% of the time we would be Studies has pointed out that LEED certified buildings could lead to ▪Outdoor temperatures in Baltimore are appropriate for ▪Reduction in energy, carbon, water and waste, resulting in savings of 30 to 97% respectively ▪Operating costs reduced by 8-9% while increasing in value up to 7.5% ▪Increases of up to 6.6% on return on investment ▪Rent increases of 3% Natural and hybrid ventilation can contribute to some major savings e.g. ▪0.8 - 1.3% savings on health costs ▪3 - 18% in productivity gains ▪47 - 79% in HVAC energy savings ▪120% for an average return of investment able to open our windows for fresh air and essentially turn off the mechanical ventilation in the building” natural ventilation about 40% (red. 5 months) of the year. ▪The law center does have a conventional HVAC system, but it is less than half the size of one that would be required for a normal building of its size. ▪The building's passive design strategies achieve very high performance and flexibility without the use of PV or solar thermal systems. ▪This last summer was a hot one for Seattle and the building was able to maintain a maximum indoor temperature of 78° F. even when it was in the 90’s outside. About natural and hybrid ventilation Natural ventilation regulates a building’s indoor climate by exploiting the natural forces created by temperature differences between the interior and exterior environment, thermal displacement within the building and winds around the building. The air is kept fresh by controlling air replacement, typically by using windows in the building’s facade and/ or roof. Ventilation is achieved by automatically opening and closing windows depending on conditions inside and outside the building and the need for fresh air. Because natural forces are free, natural ventilation is extremely energy-efficient compared to traditional ventilation solutions and this means that natural ventilation systems are both environmentally-friendly and very economical to run. Hybrid ventilation is a combination of natural and mechanical ventilation and exploits both systems as required. This entails either interchangeable periods of natural ventilation and mechanical ventilation, or a balancing of the two principles such that mechanical ventilation takes over when the external conditions so require. The result is an effective and energy-efficient ventilation solution that maintains healthy indoor climate and comfort. In order to use a hybrid ventilation solution conditions for the use of natural ventilation must be in place. Hybrid ventilation solutions, like all other solutions that utilise natural ventilation, are based on the principle of providing healthy indoor climate and comfort, delivered with minimal energy consumption and at minimal cost. Natural and hybrid ventilation is suitable for different buildings and constructions Buildings/constructions Natural ventilation Hybrid ventilation √ √ √ √ √ √ √ √ √ √ √ √ √ √ √ √ √ √ √ 01 Offices 02 Schools 03 Multi halls and sports halls 04 Shopping streets 05 Atriums 06 Common areas 07 Hallways/corridor 08 Double facades 09 Deep plan spaces 10 Spaces with high heat loads 11 Spaces with limited external openings The choice of either natural or hybrid ventilation as the optimal solution depends on the specific purpose and building/construction 3 10 benefits of natural ventilation 01 Beautiful architecture ▪No unsightly pipe-work or duct penetrations and no space consuming ventilation units. ▪Possibility of increased ceiling heights, as natural ventilation does not require suspended ceilings. ▪More daylight and transparency, for example, using atriums that can be used for natural ventilation. 02 Lowered energy consumption ▪Natural ventilation consumes less energy than a comparative mechanical ventilation system. ▪The use of hybrid ventilation could reduce the energy consumption even further. 03 100% use of space ▪With natural ventilation you will get full utilisation of the building floor plate and floor to ceiling height, since there are no need for space for large air handling units and equipment rooms. ▪A mechanical ventilation system obtains up to 6.5% of a buildings floor area compared to only 0.2% for a natural ventilation system. 04 Green profile ▪Buildings account for up to 30-40% of total energy consumption. ▪Natural ventilation has very low energy consumption and thus a very limited CO2 emission. ▪ 24-71% saved carbon emissions with natural ventilation instead of mechanical ventilation. 05 High user satisfaction ▪With a natural ventilation solution from WindowMaster it is easy to divide your building into different zones e.g. an office space in order to address several demands. ▪Users always have the option to override the automatic control, therefore providing high satisfaction. ▪In air-conditioned buildings, only 50% of the occupants are satisfied whereas in naturally ventilated buildings 77% of the occupants are satisfied with indoor temperature. 06 Gentle refurbishment ▪With natural ventilation, it is possible to establish a good indoor climate in for example protected buildings, without the need to break through walls and ceilings with ducts and making rooms for large ventilation units. ▪Natural ventilation is an obvious choice if the building should replace the old windows with newer ones. Here you can easily install actuators for natural ventilation. 07 Fast refurbishment ▪The refurbishment can be completed very quickly, which allows the building occupants to have minimal disruption if you choose natural ventilation rather than mechanical ventilation. This may also enable you to avoid having the users of the building relocated while renovation takes place. 08 Lower expenditure ▪Fewer and less expensive components and construction work are some of the contributing factors that natural ventilation the low cost option for a better indoor climate. ▪Building life cycles cost (capital cost, operating cost and maintenance) is 5 times cheaper with natural ventilation compared to mechanical ventilation and 2.5 times cheaper with hybrid/mixed mode ventilation. ▪Less than 1 year payback or an average ROI (return of investment) of at least 120% for natural ventilation and mixed-mode systems, due to energy, health and productivity benefits 09 Minimal maintenance ▪No filter replacement. ▪No dirty ducts to be cleaned. 10 Better indoor climate ▪Studies have shown that people who are staying in buildings with natural ventilation have fewer building related symptoms such as headaches, eye irritation etc. ▪Increased productivity gains of 3-18% compared to mechanical ventilation and savings on health cost of 0.8 – 1.3%. ▪Sick building syndromes symptoms can be reduced by more than 65% with a natural ventilation solution. 4 Ventilation principles The driving forces in natural ventilation are thermal buoyancy and wind pressure on buildings. The design of the building, the form of the window openings and location have a significant impact on the quality of the indoor climate Natural ventilation is driven by three basic ventilation principles 01 Single-sided ventilation An opening in one side of the room. The amount of fresh air coming into the room is limited by single-sided ventilation 03 Stack-ventilation Caused by a height difference between openings – i.e. between façade and roof window. The ventilation is primarily driven by warm air rising to the top creating a pressure difference 02 Cross-ventilation Openings in two or more facades can create crossventilation in a room. The ventilation is powered by differences in wind pressure on the facades in which the window openings are located 02 01 03 5 Obtain up to 22 LEED points with a WindowMaster solution WindowMaster’s indoor climate solutions have been put to the test and have been evaluated to see how many LEED (v41) points they have an influence on. This showed that a proper and well designed natural ventilation system has an influence on up to 22 LEED points out of a total 110 points. One of the important factors to achieve these points is to have an intelligent demand controlled system with the possibility for features such as positioning control and feedback of the actuator, threespeed actuator operation etc. Figure 1 shows how many credits natural ventilation, WindowMasters control system, are able to achieve in the different categories. 1. Refers to LEED Version 4 Selected LEED categories Our comfort ventilation solutions Possible points NV Advance® NV Comfort® Plus NV Comfort® Standard Energy & Atmosphere Fundamental commissioning and verification Required √ √ √ Minimum energy performance Required √ √ √ Building-level energy metering Required √ 0 0 Fundamental refrigerant management Required √ √ √ Optimize energy performance 18 1-10 1-10 1-10 Advanced energy metering 1 1 0 0 Enhanced refrigerant management 1 1 1 1 5 1-3 1-3 1-3 Minimum indoor air quality performance Required √ √ √ Enhanced indoor air quality strategies 2 2 2 2 Construction indoor air quality management plan 1 1 1 1 Indoor air quality assessment 2 2 2 2 Thermal comfort 1 1 1 1 Acoustic performance 1 1 1 1 Material & Resources Building life-cycle impact reduction Indoor Environmental Quality Figure 1: With natural ventilation you can obtain 22 out of 110 points About LEED LEED (Leadership in Energy & Environmental Design) is a green building certification program that recognizes best-in-class building strategies and practices. This initiative was developed by the USGBC to promote and direct buildings into more sustainable practices. Within each of the LEED credit categories, projects must satisfy prerequisites and earn points. There are four levels of certification – the number of points a project earns determines the level of Certified 40-49 Points Silver 50-59 Points LEED certification that the project will receive. Typical certification thresholds are listed in Figure 2. Gold 60-79 Points Platinum 80+ Points Figure 2: The four LEED certification levels 6 Benefits of using the LEED certification systems Energy savings The energy consumption and the consequent reduced energy costs, is one of the defining features of any green building. Energy efficiency has a significant impact on the overall running costs of a property, as energy prices rise then the operational energy efficiency will more likely become one of the important drivers for occupier demand. Estimates for the reduction in a green building’s energy use compared to a conventional code-compliant building range from 15% - 35%2 (Based on LEED-certified buildings in the United States).3 Energy Savings for LEED cerfied buildings 40 35 Reducon in energy use compared to convenonal code-compliant buildings (%) There are a wide range of economic and environmental benefits to sustainable design, often achieved through the use of standards, rating, and certification systems. According to a study of LEED certified buildings, the USGBC has found that energy, carbon, water, and waste can be reduced, resulting in savings of 30 to 97% respectively. Operating costs of green buildings can also be reduced by 8-9% while increasing in value up to 7.5%. Many sustainable buildings have also seen increases of up to 6.6% on return on investment, 3.5% increases in occupancy, and rent increases of 3%. Other benefits of green buildings, such as higher productivity and increased occupant health, have been attributed to better indoor environmental quality. 30 25 20 15 10 5 0 LEED Cerfied LEED Silver LEED Gold Figure 3: Energy Savings for three LEED certified buildings with different certification levels Productivity and health benefits From a business perspective, there are clear incentives for improving employee health and productivity. Research suggests that by making even small improvements to factors such as productivity, health and wellbeing, businesses can experience greater financial benefit than they would from more efficient resource use in building operations. Figure 4 illustrates the potential benefits which LEED certified buildings could give regarding productivity, health etc. OUTSIDE VIEWS Mental Funcon & Memory Call Processing Hospital Stays 6-12% 10-25% 8.5% FASTER BETTER SHORTER DAYLIGHT SYSTEMS Producvity Increases by Students achieve 5-14% HIGHER TEST SCORES and learn 20-26% FASTER 18% Workers are MORE PRODUCTIVE 23% from beer lighng 15-40% INCREASE in Retail Sales 11% from beer venlaon 3% from individual temperature control Figure 4: Net present value analysis of the operational cost and productivity and health benefits of LEED certified buildings 2. Gregory H. Kats, The costs and financial benefits of green buildings, October 2003 3. Source: https://www.wbdg.org/resources/gbs.php 7 Focus on employees well-being is a good business One of the more hot topics of today is the health and productivity of the employers and here the numbers clearly speak for themselves. that is many times larger than any other financial savings associated with an efficiently designed and operated building. The World Green Building Council (GBC) published in 2015 a comprehensive report on Health, Wellbeing & Productivity in Offices. Here it was pointed out that the staff costs, including salaries and benefits, typically account for about 90% of a business’ operating costs (Figure 5). It follows that the productivity of staff, or anything that affects their ability to be productive, should be a major concern for any organisation. 1% Energy costs 9% Rental costs 90% Staff costs in salaries and benefits Figure 5: Typical business operating costs4 An improvement in employee health or productivity can have a huge financial implication for employers – one High productivity and less SBS symptoms Several studies have been looking at the productivity gains, SBS symptoms and the health impact from natural and hybrid ventilation. Figure 6 illustrates the results from different studies from the last 30 years, showing an improvement ranging from the lower end of 3.2% to a massive 18.0%. 24% 18% perceived producvity increase 20% Average improvements 8.5% $3,900 per employee 16% 9.75% perceived producvity increase 12% 5.1% 40% reduced SBS symptoms 8% 7.7% 67% reduced SBS symptoms 3.2% 7% reduced absenteeism 4% 0% 7.5% increased testscores Sterling and Sterling 1983 Skov et al. 1990 Heschong Mahone 2002 Kroeling et al. 1988 Leaman 2001 Rowe 2002 Figure 6: Annual Productivity Gains from Mixed-Mode Conditioning and Natural Ventilation5 4. Browning B. (2012) The Economics of Biophilia: Why designing with nature in mind makes sense. David Clark (2013). What Colour is your Building?: Measuring and reducing the energy and carbon footprint of buildings. 5. Source: http://cbpd.arc.cmu.edu/ebids 8 Productivity and energy benefits A comprehensive analysis in 2004 by Carnegie Mellon6 concluded that natural ventilation or mixed-mode conditioning could achieve 0.8 - 1.3% savings on health costs, 3 - 18% productivity gains and 47 - 79% in HVAC energy savings, for an average ROI (Return Of Investment) of at least 120%. The more in depth numbers can be found below. Eight studies have shown that natural ventilation and mixed-mode systems can pay for themselves in less than one year due to energy and productivity benefits. ▪Natural ventilation and mixed-mode systems yield; ▪annual energy cost savings of $110 per employee ▪health cost savings of $60 per employee ▪annual productivity gains of $3,900 per employee ▪total savings of $4,070 per employee annually 8 studies have shown that natural ventilation and mixed-mode systems can pay for themselves in less than 1 year ▪The average ROI for an investment in natural ventilation or mixed-mode conditioning is 407% for new construction and 120% for retrofits. ▪In the US office sector this would mean more than $6.4 billion in energy savings each year. If only half of those buildings used natural ventilation or mixed-mode conditioning, over 40 billion kWh would be saved each year. ▪Given the average productivity and health benefits of $3,900 and $60 per employee, respectively, the total savings achieved by providing half of the U.S. workforce with mixed-mode conditioning or natural ventilation is over $118.9 billion annually (equivalent to 1% of the U.S. GDP in 2003). 6. Carnegie Mellon (2004), Guidelines for High Performance Buildings – Ventilation and Productivity 9 anum Customers with a LEED certification WindowMaster projects has in many cases, shown that it is possible to achieve a very high LEED rating with natural ventilation. View some of WindowMaster’s LEED certified projects below. Gold Silver San Diego Continuing Education Mesa College Campus, San Diego Planum Gold Prime Tower, Zürich Planum Gold University of San Francisco John Lo Schiavo, San Francisco Silver Planum Gold Qualcomm Campus Building AY & Building AZ, San Diego Planum The University of Baltimore School of Law, Baltimore Gold Silver Planum The Bullitt Center, Seattle Planum Silver Gold Green Lighthouse, Copenhagen Silver Planum G The Tower at PNC Plaza, Pittsburgh Gold Planum Silver G UN City, Copenhagen 10 San Diego Continuing Education Mesa College Campus, San Diego The facility has been awarded LEED silver certification by the U.S. Green Building Council, making it the district’s fourteenth LEED certified facility. Natural ventilation and daylighting played aPlanum big part, while sustainable construction materials and high-efficiency plumbing and mechanical systems also contributed to the green qualifications. Gold Silver This $22.5-million school project consolidates programs such as English as a second language and disability support into a bright and airy two-story learning center of 37,700 sq. ft. (3500 m2). Project engineers have incorporated sustainable features such as natural ventilation and natural lighting to reduce the building’s energy use by 43% compared with state requirements. The WindowMaster solution The natural ventilation occurs via high-level automated façade windows in the classroom. In the back of each classroom, there are high-level automated vents, which can lead the air into the common areas (hallway) where the air is ventilated out through the high-level automated windows in the clerestory. Each teacher controls the classroom temperature through a single switch on the wall that offers the choice between natural and mechanical cooling. When the temperature falls within the comfort zone (as it does the majority of the year), the natural ventilation system disengages the mechanical air conditioning and automatically opens the windows. In the design discovery process, teachers told that they love to open the windows and doors. This building encourages that behavior, so it is expected that the teachers will choose natural ventilation most of the time. WindowMaster was selected to supply the more than 100 motors for the natural ventilation solution for its MotorLink® technology. MotorLink® is a digital data communication technology designed to provide improved control and functionality where automated windows and natural ventilation are part of a building management system. 43% reducement of the building’s energy use, compared with state requirements 11 University of San Francisco John Lo Schiavo, San Francisco The University of San Francisco (USF) needed to replace its cramped 1966 Harney Hall, built when science enrollments were just half of today’s levels. Construction of a new state-of-the-art science building (S.J. Center for Science and Innovation) located in the center of the USF main campus, immediately adjacent to two existing buildings. Classrooms include chemistry wet-labs with fume hoods, physics labs, lecture halls, computer labs, and community spaces. The 61,610 sq. ft.building had a budget of $43M and was awarded LEED Gold. Planum Gold The WindowMaster solution A green feature of the mostly glass building are the climate-controlled windows, which open or close depending on the temperature and have features to prevent reflectivity and use ambient heat to help control temperature. In line with the campus’ wind patterns, the building is designed to accommodate natural ventilation. Piping systems embedded in the concrete run water hot and cold, which helps control the building’s temperature.7 42% savings from tle 24 baseline Passive venlaon Natural venlaon / Radiant Floor System Acve venlaon Type 1: Intensive Lab Space 100% Outside Air Type 2: Overhead / Displacement Type 3: Underfloor Air 7. Source: http://issuu.com/nbbj/docs/usf-case-study 12 Green Lighthouse, Copenhagen Green Lighthouse was Denmark's first certified sustainable building, having become the first building in the country to achieve a LEED Gold rating. Planum Gold Green Lighthouse, a faculty building for the Faculty of Science at the University of Copenhagen in Denmark, is designed to optimize the well-being of the people working in the building as well as being CO2 neutral. The 10,000 sq. ft. (950 m2) was built as a demo building in connection with the UN Climate Conference, COP15, held in Copenhagen in 2009, with a sharp focus on energy consumption and renewable energy. The WindowMaster solution An important element in achieving CO2 neutrality is using technology that reduces the use of electricity. Traditional ventilation systems are usually one of the great electricity consumers. Automatic window control (natural ventilation) has therefore been installed to ensure fresh air in the building. Mechanical ventilation is only in operation for a very limited part of the year. NV Advance® from WindowMaster ensures that the building is at all times using the most efficient form of energy. This is done by continuous measurement of room temperature, CO2 and light levels and using the weather station records of outdoor temperature, wind speed and direction, sunshine and rain. Based on all these data, NV Advance® determines which type of ventilation is optimal and whether there is a need for heating or additional electrical lighting. Solar cells For most of the year, ventilation is provided solely via the automatic control of windows that are opened and closed in each room/area depending on the need for ventilation and fresh air. On cold days, mechanical ventilation with heat recovery is used. On warm days, cooling is provided in the large meeting rooms. Atrium ventilation Solar heang system LED Hybrid venlaon Fresh air intake Sun screening Night cooling Two years after Green Lighthouse at the University of Copenhagen opened the doors, it became the first building in the country to be certified as a sustainable building. Green Lighthouse was given a LEED Gold rating. Furthermore, the building was chosen to become a pilot project in order to test the Danish certification system, DGNB-DK, and was awarded with DGNB Silver. Highly insulang and ght climate screens Cast shadow Heang pump Solar heang container WindowMaster touch screen 13 Prime Tower, Zürich Zurich’s 126 metre high 430,000 sq. ft. (40,000 m2) Prime Tower, the tallest building in Switzerland, has been designed by architects Annette Gigon and Mike Guyer to be at the forefront of sustainable building technologies. Planum Gold The development houses offices, restaurants and bars, retail outlets and support facilities. As part of the sustainable construction of the building it features natural ventilation controlled by the MotorLink® automated window control system. The WindowMaster solution Schüco, in partnership with façade designers Emmer Pfenninger Partner and façade manufacturer Dobler Metallbau, delivered an installation of 6,910 WindowMaster chain actuators for the automation of 1,382 parallel opening windows including one espagnolette locking motor for each window. These MotorLink® actuators are connected to MotorLink® MotorControllers to provide power and control primarily for natural ventilation. The windows in Prime Tower are large rectangular parallel opening windows, which weigh approximately 360kg. To safely operate under load each window is equipped with four WindowMaster chain actuators and one special espagnolette/locking actuator. The window actuators communicate with the MotorController via digital MotorLink® technology. Exact feedback concerning position as well as accurate synchronisation of the actuators is therefore ensured. The chain actuators and other components were tested and approved according to strict performance standards. 14 Qualcomm Campus Building AY & Building AZ, San Diego Qualcomm's Pacific Center Campus consists of Building AY, an approximately 357,000-sq-ft, six-story office/laboratory facility and Building AZ, an approximately 67,000-sq-ft, two-story multi-use facility that includes a learning/ conference center, kitchen/café, a health/fitness center and a theatre. The buildings are being designed to achieve LEED gold certification. Sustainable features include an architectural bioswale designed to remove silt and pollution from surface runoff water in the interior courtyard, natural daylighting and a state-of-the-art façade that controls heat and glare. It is also one of the largest naturally ventilated buildings in the country. These high-performance features create a highquality work environment. The WindowMaster Solution Planum Gold Photographer: Chad McDonald Source: www.flickr.com WindowMaster has supplied almost 1000 actuators for two buildings at the Qualcomm Pacific Centre in San Diego, USA. ‘The buildings are designed to optimize passive design strategies to achieve high-performance results and provide a high-quality interior workplace environment to boost employee productivity. The buildings’ east/west solar orientation and narrow floor plates promote natural ventilation and daylighting, and a high-performance façade design controls heat gain and glare. 15 The Tower at PNC Plaza, Pittsburgh The Tower at PNC Plaza is a 800,000 square feet headquarters for the PNC bank in Pittsburgh, Pennsylvania. Planned as a landmark building, both with regards to design and in terms of environmental friendly solutions, the 33-story tower has a construction budget of approximately $240 million. Incorporating state-of-theart green technology, including a double-skin facade and solar chimney, the building was designed to exceed LEED Platinum certification and to be the greenest office tower in the world. Planum The WindowMaster Solution WindowMaster has delivered more than 6300 actuators to control 700 parallel windows in the outer double skin façade and 1450 automated air vents in the inner facade. From its one-of-a-kind, breathable double skin to its innovative workplace strategy, The Tower drives performance to new levels. The building “breathes” with a double-skin facade: a natural ventilation system that has a glass outer weather and air barrier and an inner layer with automated air vents, a wood curtain wall, and manually operated sliding doors. A series of automatic sensors on both layers open up the building for air when the weather permits. The main reason for choosing WindowMaster as a supplier for this project is the MotorLink® technology that enables. genuine synchronization of four actuators on one parallel window and exact position control and feedback via the BACnet BMS. “ The research told us that 45% of the time we would be able to open our windows for fresh air and essentially turn off the mechanical ventilation in the building. We had to create a double skin that operated through a building control system that would open during the optimal weather days…” Doug Gensler, Managing Director | Gensler Boston 16 The University of Baltimore School of Law, Baltimore The new home of the John and Frances Angelos Law Center at 192,000 sq. ft. unites classrooms, faculty offices, administrative space, and the law library under a single roof for the first time in the history of the school. The building, located at the prominent intersection of Mount Royal Avenue and Charles Street, functionally and symbolically defines the Law School as an academic and social nexus, offering state-of-the-art teaching and learning facilities.8 Planum The WindowMaster solution WindowMaster has provided more than 1000 MotorLink® actuators integrating the intelligent facades with the LONworks Buildings Management System. This enables full control of each motorized window. The windows will then be automatically closed when the aircondition is on and made available for the users to open and close at will by the manual override switches, when the aircondition is off. Operable windows are provided in regularly occupied spaces, allowing users to have direct control of their environment. Occupants have local control of operable windows in all office, teaching and library spaces, and are notified of favorable outdoor conditions by means of a green indicator light that communicates appropriate times to open a window. Atrium operable windows are fully controlled by the building automation system based on the quality of outdoor conditions. Atrium smoke exhaust fans are activated at low speed in natural ventilation mode to guarantee good cross ventilation through all spaces, and acoustically protected and fire-protected transfer openings are provided from perimeter spaces to the atrium. Outdoor temperatures in Baltimore are appropriate for natural ventilation about 40% (red. 5 months) of the year. Therefore, a mixed-mode approach to the interior climate is taken, with mechanical ventilation, heating, and cooling during the extreme seasons and natural ventilation during spring and fall. The law center does have a conventional HVAC system, but it is less than half the size of one that would be required for a normal building of its size. 8. J. Michael Barber is a senior associate with Ayers/Saint/Gross 17 The Bullitt Center, Seattle The Bullitt Center is a high performance urban office building, demonstrating a commercially structure with essentially no environmental footprint is possible. The six-story, 52,000 sq. ft. building was evaluated toward the goal of net zero energy, water and waste – resulting in an unprecedented EUI of 10kbtu/sf/yr. Planum The Bullitt Center is all about changing the norms of design and construction for a typical office building. The challenge PAE, the project’s mechanical and electrical engineer, accepted was to design the ventilation system to keep the occupants comfortable while using radically less energy compared to a standard office building. The three principle strategies used to create a comfortable office environment are a high-performance envelope, passive cooling through motorized windows, and a radiant slab to heat and cool the space. The WindowMaster Solution Justin Stenkamp of PAE feels that the new norm should be to have the occupants and the building operator sharing the strategies to support the efficient operation of the building. The occupants need to buy-in to the goals and understand how to optimize the energy efficiency of the building. At the Bullitt Center there is an override for the control of the windows on each occupant’s computer and a hard switch in each tenant space. In a standard office building there is a disconnect between the weather outdoors and the interior temperature. We all are familiar with the chill when stepping into a typical office building from the summer street. The old style is to have the building maintain a standard temperature all year regardless of what is happening outside. At the Bullitt Center it’s different. In summer the interior will be a bit warmer and will suit your summer clothing. This last summer was a hot one for Seattle and the building was able to maintain a maximum indoor temperature of 78° F. even when it was in the 90’s outside. The interior spaces are controlled by a computer that acts as the brains of the building, translating the outdoor environmental conditions into reactions at the envelope of the building – such as employing the exterior louver shades or opening the windows, as heating or partially cooling the radiant slab at each floor.9 “ To help cut energy consumption to 23 percent the amount of a traditional building its size, natural light will account for 82 percent of all lighting, thanks to oversized windows and higher ceilings that help get light farther inside. And so will air, as the building’s electronic ʻbrainʼ automatically opens and shuts the windows based on temperature needs, eliminating the need for airconditioning units.” Source: Time Inc, June 2012 9. Source: http://www.bullittcenter.org/2014/01/22/natural-ventilation/ 18 UN City, Copenhagen The 560,000 sq ft (52,000 m2) building located in Copenhagen (Denmark) consists of two campuses that houses ten United Nations agencies which currently accommodates 1,200 employees representing more than 100 different nationalities. Planum The building is built with a large focus on sustainability and environmental friendliness, and the calculated energy consumption has been designed to use at least 55%, less than 4.5kbtu/sf/yr (50 kWh/m2/year) less energy than expected from a similar-sized office building UN City in Copenhagen is the first United Nations building to receive the prestigious platinum LEED certification thanks to its environmentally-friendly design. Additionally, it has been awarded with the European Commission's Green Building Award for New Buildings. The WindowMaster solution The building has a façade cladding of white perforated aluminum shutters, developed by 3XN and contractor Pihl specifically for the UN City. The shutters ensure solar shading without blocking the view or the daylight. Since the facade is divided into three meter long modules, it is possible for the employees to control the sunshade from their computers. The result is an improved indoor environment, and a dynamic façade expressing a building full of life. The WindowMaster package for this project is to deliver 1500 special made 24V motors for torque control of the solar shading panels. 19 Contact us for further information Our sales consultants are spread throughout the country and are always ready to help you. For more information about LEED, use the QR-code to go to our website. www.windowmaster.com Tel.: +44 01536 510990 UK +44 (0) 1536 510990 [email protected] Other markets +45 4567 0300 [email protected] ©WindowMaster 2016 ®WindowMaster is a registered trademark used under license by WindowMaster Group www.windowmaster.com