Solar shading control Automated natural ventilation and solar shading control

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1 Solar shading control Automated natural ventilation and solar shading control A joint strategy between two of the most important passive measures in a room, automated natural ventilation and solar shading, ensures for example a high level of comfort, increased productivity and reduction of absenteeism with a minimum of electricity usage

2 Why solar shading? Effective control of the sun screening is an important contributor to maintaining a comfortable indoor climate as the sun screening can be used as both a shield against extreme overheating and as additional insulation in the winter during certain times. Nowadays, large glazed windows are frequently chosen in the architecture due to a wish for a transparent and cleaner facade with an aesthetic look. The highperformance glazing ensures plenty of daylight, increased comfort, good insulation and optimal energy consumption if designed correctly. Some downsides are that the sunlight may cause overheating, disruptive reflections on screens and discoloration of the (indoor) furniture and décor, which in many cases leads to a poor indoor climate. An effective solar shading solution can prevent a poor indoor climate throughout well-design and controlled solutions. The ES-SO and REHVA guidebook on Solar Shading, published in 2010, presents a summary of scientific research showing the influence of the use of daylight on factors related to worker and student productivity: By maximizing the use of daylight without glare and providing daylight responsive lighting controls, a median productivity benefit of 3.75% was found by Carnegie Mellon University. On average, major health complaints are between 20% and 25% lower for occupants close to an exterior window, compared to those who work in the interior core without access to view and direct daylight. Access to windows and daylight resulted in a 15% reduction of absenteeism. Direct sun penetration into classrooms, especially through unshaded east or south facing windows, is associated with negative student performance. Students with adequate natural daylight in their classrooms showed 20% faster progress in math tests and 26% in reading tests during one year. From the above it may be concluded that natural daylight has a significant and positive influence on occupant health, wellbeing and productivity. However, adaptive control of daylight i.e. movable solar shading is needed to guarantee the conditions of good visual comfort and indoor temperature.

3 By maximizing the use of daylight without glare and providing daylight responsive lighting controls, a median productivity benefit of 3.75% was found by Carnegie Mellon University Direct sun penetration into classrooms, especially through unshaded east or south facing windows, is associated with negative student performance On average, major health complaints are between 20% and 25% lower for occupants close to an exterior window, compared to those who work in the interior core without access to view and direct daylight

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5 Different kinds of solar shading solutions Solar shading can be fixed or flexible. Fixed measures, such as window sizes, orientation, shading by other buildings or surroundings and the total solar energy transmission of the glazing cannot be varied according to the season or the time of day, which in some cases results in disadvantages compared to the flexible systems. Flexible measures (venetian or roller blinds etc.) allow the user and control system to have influence on how much solar radiation that enters the room. Accordingly, the heating energy demand in winter can be reduced as much as possible, while overheating and the cooling energy demand, can be avoided during the summer. Venetian blinds have the potential of providing shading and at the same time one may still be able to look out of the window, as the blades in many cases can be angled. Flexible systems are therefore preferred to fixed systems. Photo: Schmidt Hammer Lassen Architects

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7 Goes hand in hand with natural ventilation Automated natural ventilation and solar shading are two of the most important passive measures for room conditioning in a building. Both ensures a high quality indoor climate with a minimum of electricity usage. As both technologies cover the same aspect of providing a great indoor climate it is therefore ideal to implement both natural ventilation and the solar shading in a joint strategy

8 Control Integrating the sun screening function into your indoor climate control system allows venetian blinds, awnings etc. to be controlled automatically, both in summer and winter, so that the position of the sun screens can be continually adapted to the prevailing lighting and heating situation in a room. This allows an optimal use and exploitation of the sun screening product as well as optimising the use of solar thermal energy. The actual control is based on measurements of lux and temperature. The control systems, NV Advance og NV Comfort, has a built-in sun screening controller for venetian blinds and awnings. The controller includes functions such as timed up/down function linked to a calendar, up/down function depending on lux levels (alternatively watt/m²), indoor temperature and the option of manual input. There are various control strategies for the solar shading solution depending on the type of shading as well as the actual building and its needs. E.g. for the venetian Optimum position of the venetian blinds ensures the optimal balance between daylight utilization and heat protection

9 blinds controlling the angles of the blades in the optimum position means that the system at a very precise level can control the amount of daylight and glare that enters the room and at the same time have enough view out. If you are interested in learning more about how roller blinds vs venetian blinds are controlled, please reach out to your local WindowMaster office. Smoke ventilation Natural ventilation Mechanical ventilation Lighting As previously mentioned, there is a synergy between natural ventilation and solar shading because both are key to maintaining a comfortable indoor climate. Therefore, it is also ideal to control these technologies with the same system. This can be handled by either NV Advance or NV Comfort, which are two of WindowMasters control systems. Both systems are based on intelligent software that controls automated natural ventilation with data input on for example wind speed and direction, indoor and outdoor temperature and CO 2 level. These systems have the possibility to unite other technologies and control these for a holistic and complete solution. By doing so, it is possible to avoid many of the common pitfalls that exist when multiple systems / technologies have to be integrated. Solar shading Heating Cooling One control system integrated seamlessly with other solutions

10 Cases Numerous WindowMaster projects control both the natural ventilation and the solar shading. View some of WindowMaster s projects on the next pages

11 Ørestads Gymnaium Type of shading : External screens in the façade Building type : University Ventilation Architect Consultant : Natural ventilation : 3XN A/S : Søren Jensen A/S : Denmark Green Light House Type of shading : Internal venetian blinds in the façade and roof Building type : Office Ventilation Architect Consultant : Mixed mode ventilation : Christensen & Co. Arkitekter A/S : COWI A/S : Denmark Aarhus municipality Type of shading : External roller blinds in the façade Building type : Office Ventilation Architect Consultant : Mixed mode ventilation : Schmidt hammer lassen : SWECO : Denmark Solhuset Type of shading : External roller blinds in the façade Building type : Daycare Ventilation Architect Consultant : Mixed mode ventilation : Christensen & CO Arkitekter : Rambøll : Denmark

12 Moesgård Museum Type of shading : External screens in the façade Building type : Museum Ventilation : Natural- and mixed mode ventilation Architect : Henning Larsen Architects Consultant : COWI A/S : Denmark Rigshospitalet Type of shading : External venetian blinds Building type : Hospital and CompactSmoke Ventilation : Smoke ventilation and some areas incl. natural ventilation Architect : 3XN A/S Consultant : SWECO : Denmark Photo: Arkitema-Achitects, creativecommons.org/licenses/by/3.0/ Nexus Cph Kalvebod Brygge Type of shading : Venetian blinds located between the two window panes Building type : Office and FlexiSmoke Ventilation : Natural ventilation with night time cooling and smoke ventilation Architect : Arkitema Architects Consultant : MOE : Denmark HafenCity Universität Type of shading : External venetian blinds in the façade Building type : University Ventilation Architect Consultant : Smoke ventilation and night time cooling using natural ventilation : CODE UNIQUE Architekten : Ridder + Meyn : Germany

13 Haus der Ärzte Type of shading : External venetian blinds in the façade Building type : Office Ventilation Architect : Natural ventilation : Fthenakis Ropee Architektenkooperative : Germany Max-Planck-Gymnasium Type of shading : External screens in the façade Building type : School Ventilation Architect Consultant : Natural ventilation : Yöndel. Zimmerlin Architekten, Karlsruhe : Bender + Urich Ingenieurbüro, Karlsruhe, IBB Ingenieurbüro Bath, Karlsruhe, WindowMaster GmbH, Hamburg : Germany Wortmann Schuh Holding KG Type of shading : External screens on the roof windows Building type : Office Control solution : FlexiSmoke Ventilation : Natural ventilation and smoke ventilation Architect : Dipl. Ing. (FH) Andre Rohde : Germany Wasgenring Schule Type of shading : External venetian blinds in the façade Building type : School Ventilation Architect Overall management : Natural ventilation : STÄHELIN architectes : PPEngineering : Switzerland

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15 Buildings with well-functioning solar protection can cut the investment cost for cooling and ventilation installations, reduce energy use and create the conditions for good thermal and visual comfort. Helena Bülow-Hübe, Research Assistant et al., University Lund

16 WindowMaster aspires to protect people and the environment by creating a healthy and safe indoor climate, automatically ventilating spaces with fresh air through facade and roof windows in commercial buildings. We offer the construction industry foresighted, flexible and intelligent window actuators and control systems for natural ventilation, mixed mode ventilation and smoke ventilation of the highest quality. WindowMaster employs around 135 highly experienced cleantech specialists in Denmark, Norway, Germany, United Kingdom, Ireland, Switzerland and United States of America. In addition, we work with a vast network of certified partners. With our extensive expertise built up since 1990, WindowMaster is ready to help the construction industry meet its green obligations and achieve their architectural and technical ambitions. windowmaster.com WindowMaster 2018 WindowMaster is a registered trademark used under license by WindowMaster International. We reserve the right to make changes.