Passive Design/OTTVWeek 1

Discussion: Green Building Survey

Q1: Would you like to work in a green building?

Q2: Would you like to live in a green building?

Q3: Is Green Building more expensive to construct than standard building designs?

Q4: Should every new building designed in Vietnam be a Green Building?

Q5: Can a building with Air Conditioning be called a Green Building?

Q6: Should all Green building include onsite renewable energy production (eg Solar or Wind power)?

Q7: The most important party (group of people) in achieving “Green Building” is…

Government incentives to build Green

4 14%

The government to “lead by example” and build Green Buildings

7 25%

Stricter laws on building design

5 18%

Advertising campaigns about Green Building

1 4%

Teach Architects and other professionals about Green Building

2 7%

Support industries providing eco-products or highly efficient equipment

5 18%

Other 4 14%

Q8: The best way to promote Green Buildings in Vietnam is…

Energy Efficiency 7 25%

Water Efficiency/recycling/ harvesting

1 4%

Sustainability of Materials 3 11%

Renewable Energy 4 14%

Management 8 29%

Other 5 18%

Q9: What is the most important consideration when designing Green Buildings in Vietnam?

Passive Design Definition

Design where climatic and site conditions are considered to keep the building naturally cool in summer and warm in winter, with adequate ventilation and a comfortable level of natural light while requiring no input of energy for thermal control.

Hybrid systems use a variety of cooling options (including air-conditioning) in the most effective way. They take maximum advantage of passive cooling when available and make efficient use of mechanical cooling systems during extreme periods.

Tools for Passive Design

SoftwareData and Information

Autodesk Ecotect Analysishttp://usa.autodesk.com/ecotect-analysis/

Ecotect Analysis:

Whole-building energy analysis—Calculate total energy use and carbon emissions of your building model Thermal performance—Calculate heating and cooling loads for models. Water usage and cost evaluation—Estimate water use inside and outside the building.Solar radiation—Visualize incident solar radiation on windows and surfacesDaylighting—Calculate daylight factors and illuminance levels Shadows and reflections—Display the sun’s position and path

IEShttp://www.iesve.com

ARUP Passive Design Assistant Toolhttp://www.arup.com/Publications/Passive_Design_Assistant.aspx

Climate Data: Temperature, (degree days)http://www.degreedays.net/QCVN 02 : 2009/BXD

Climate Data: HumidityQCVN 02 : 2009/BXD

Climate Data: RainfallQCVN 02 : 2009/BXD

Sun path diagramhttp://solardat.uoregon.edu/SunChartProgram.htmlhttp://www.suncalc.net

Wind rose(Ecotect)

Wind rosehttp://www.windfinder.com/

Solar Irradiation/Insolation

Solar Irradiation/Insolationhttp://www.gaisma.com/en/dir/vn-country.html

Factors affecting Microclimate: Elevation, Topography, Water Bodies, Vegetation, Heat Island affect

Passive Design Exercise

Passive Design ExerciseLocation: Hoa Thach, Ha Noi (near Hoa Binh)Project: 4 villas and ladscaping, Each villa: 180m2

Consider:- Microclimate- Orientation of buildings- Orientation of living spaces/bedrooms- Floorplate? How many levels?- Ventilation- Glazing (type and dimensions)- Shading (type and dimensions)- Landscaping- Innovative features?

Fundamentals of Passive Design

Fundamentals of Passive Design

Orientation-Site Selection-Climatic conditions-Prevailing winds

Passive Heating (Hanoi?)

Ventilation-Cross Ventilation -Stack Ventilation

North Facing House (Hiroshi Sanbuichi, Yamaguchi, Japan)

Shading-Overhangs (eaves)-Shading device (louvers, -planting

Shading

Louvers and shading devices

Glazing-Window to Wall ratio

Glazing-Low-E (Emissivity)-tinted-reflective coating-Double (triple) glazing

Concepts-SHGC (Solar heat gain coefficient)-Emissivity-VT (Visible Transmittance)

Glazing and Insulation> Saigon Case study

Materials (Hot tropical and Hot dry summer)

*Southern Hemisphere

Materials (Courtyard and Nightime cooling)

*Southern Hemisphere

Insulation: R Value/U-Valuehttp://www.u-value.net/berechnung/u-wert-rechner/

Insulation: R Value/U-Valuehttp://www.u-value.net/berechnung/u-wert-rechner/

Where to install insulation?- Under the roofing material>reduce radiant heat gain.- In the ceiling> reduce heat gain and loss- In walls> reduce conducted, convected and radiant heat transfer-Underside of suspended floors> In hot or humid climates where AC is used

Thermal Mass

Seasonal Thermal Mass -Europe: Switzerland, Berlin (Germany), IrelandIce storage-Rokko Shidare observatory

Seasonal Thermal Mass & Ice Storage

Thermal Mass and “Earth coupling”

Underground thermal control (tubes/chambers)

Evaporative Cooling- Sweat-Botijo(Spain)

Evaporative Cooling-Pot in Pot (Zeer) – Northern Africa-Coolgardie safe (1890’s) - Australia

Evaporative Cooling> Applications in architecture

-Effectiveness depends on difference between wet-bulb and dry bulb temperature

OTTV Overall Thermal Transfer Value

OTTV Overall Thermal Transfer Value

- QCXDVN 09/2005 (EEBC)- New version (2014?)- Used in Singapore, Phillipines, Malaysia, Jamaica, Hong Kong,

Thailand

Term 1: Heat conduction due to absorption of solar radiation by opaque surface

Term 2: Heat conduction through opaque elements due to temperature difference

Term 3: Transmission of solar radiation through transparent elements

Term 4: Heat conduction through transparent elements

OTTV in LOTUS and calculation of reduction

Example “compliant” wall in Hanoi-35% WWR

Example “compliant” roof in Hanoi-Why terms 1 & 2?-5% glazing

Compliant Wall rotations

OTTV case study

Standard Office Premium Office

Standard Office – BASE CASE

Standard Office – WALLS applying measures 1 at a time

Standard Office – WALLS measures applied cumulatively

Standard Office – ROOF applying measures 1 at a time

Standard Office – ROOF measures applied cumulatively

Premium Office – BASE CASE-Clear double glazing assumed

Premium Office – BASE CASE-Clear double glazing assumed

Premium Office – WALLS applying measures 1 at a time

Premium Office – WALLS measures applied cumulatively

Premium Office – ROOF applying measures 1 at a time

Premium Office – ROOF measures applied cumulatively