The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June The Design of Ecological Buildings: Shading and Lighting Professor Yan Chen Professor Les Norford Department of Architecture MIT Traditional shading technology New shading technology

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June What not to do - Beijing housing: vegetation but not much shading

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June What not to do - Balconies are enclosed and no longer provide shading

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June What not to do – worst case Which way is south? Where is the window shading? Can occupants possibly be comfortable without air conditioning?

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June The Earth’s Comfort Zones Around the world people have developed energy- efficient building forms that are suited to the climate conditions of their particular location – a form of ‘solar vernacular’. They have developed simple solutions to the environmental challenges set before them: heat, cold, rain and wind. These solutions have been developed using a limited range of indigenous building materials, all of them renewable

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Climate Zones: Architecture Boston Beijing Ice Caps Tundra Mountain Continental Marine-West coastal Mediterranean Subtropical Rain Forest Savannas Steppes Deserts N

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Mediterranean Climate Closest to the ideal climate - warm but dry with mild winters. People must protect themselves from the intense heat of summer and extreme light by shading and thermal mass. Life slows down in summer, as cooling is not always affordable. Arcades and verandahs create microclimates merging the bright outside with the cold dark indoors

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Shading by Buildings - Italy

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Marine West-coastal climate Not too hot, not too cold – the oceans have a calming influence on the temperature on land. The strong winds and rain that come with the cold winter make this a good environment for people to work in, as long as they have warmth and protection A balance is required between daylight and insulation – large windows allow natural lighting and ventilation. The low embodied energy of Georgian houses, using brick, wood and glass, has proved very sustainable for over 200 years

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Subtropical Climate A pleasant climate for most of the year, but summers are humid so ventilation is a necessity. The Japanese and Chinese developed systems of dynamic walls to create buffer zones between inside and outside, providing more comfortable summer spaces. Houses in the southern US use the porch as a buffer zone. In Japan the sliding screens allow maximum cross ventilation. Chinese roundhouses contain a protected fully sustainable community

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Solar Shading Villa Shodhan, AhmadabadUnite Building, Marsailles, France Shading devices and roof gardens provide excellent shade and comfort for south facing walls

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Window shading in Mumbai, India

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Even newer buildings have at least some window shading

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June A school in Gujarat, India – note the depth of the facade

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Solar Shading Protective shading in Brazil. Adjustable louvers between fixed vertical concrete fins

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Housing in Zimbabwe – another deep façade and a good use of pre- cast concrete

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June New facade technologies many new high rise buildings in Europe are experimenting using double skin wall technology- allowing natural ventilation and adjusting to summer and winter climate conditions

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June How about a very different type of high-rise building for a hot and humid tropical climate?

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Back to Beijing - vegetation helps reduce indoor temperatures

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Vegetation and shading from overhanging surfaces – looks cool and comfortable

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Awnings and plants

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Detailed View of Shading # 1: Osuna Housing, Seville, Spain Notice strong solar orientation of the buildings on the site.

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Shading – relatively few windows on the west facade

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Winter sun for daylighting and solar heat

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Summer sun is blocked

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Detailed Look at Shading #2: Solar Village 3 Athens, Greece

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Align most buildings to face North- South

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Site orientation

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Shading system

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Note depth of south facing façade

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Shading Design 1. Determine when shading is needed

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Determine elevation and azimuth of sun when shading is needed

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Choose a shading device – fixed ….

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June … or movable

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June In hot climates, south- facing windows are best because they bring in the least heat

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Determine size of shading device Example: movable south-facing shading

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June A word about lighting Relatively easy to do with houses because room sizes are small Still important –Reduces energy for lighting –May reduce energy for cooling –Meets human needs for sunlight and contact with nature

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Assessing lighting inside a Shanghai apartment

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Use simulation to estimate indoor illuminance

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Developers and designers can get help from the research community Encourage and support research to find new ways of determining energy-efficient designs Conduct design competitions in which carefully documented estimates of energy use are a key part of submittals

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June A new technology: automatically trading off cost of windows and insulation against energy use Consider a Beijing apartment, with north and south exposures Vary window size, glazing type, and wall construction in each of the two walls Compute construction cost and operating energy Search for lowest operating energy for a given construction cost

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Search procedure Use the DOE-2 energy calculation program to estimate yearly energy use for heating, cooling and lighting Use a genetic algorithm to automatically search for the best trade-offs between operating energy and construction cost

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Trading off cost of windows and insulation against energy use – results of an automated search

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June What’s best? Construction details The most expensive but most efficient construction uses: –Large south-facing and small north-facing windows –Lots of insulation in both walls, but more in the north-facing wall All of the optimal trade-offs use double- glazed windows

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Repeat for east-west apartment

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June East-west apartment Higher energy use than an apartment facing north-south, as expected The most energy-efficient solution has windows of about 2 m 2 in the east and west walls, compared to about 8 m 2 in the south wall and 0.8 m 2 in the north wall

The Design of Ecological Buildings – Lighting and Shading International Seminar on Green Housing, Guangzhou, China, June Conclusion Developers and designers can make buildings more comfortable and efficient, by setting high goals and working with government organizations and building scientists. Better control of sun and light need not be costly and can provide a distinctive and pleasing form to buildings as well as save energy for lighting and cooling. Researchers should be encouraged to generate new designs and to pin point trade-offs between energy use and cost.