Transcript Library case study on green architecture

Library case study on
green architecture
Green architecture
Green architecture also known as “sustainable
architecture” or “green building” is an
approach to architectural design which
emphasizes the place of the buildings with both
local ecosystems & global environment.
It aims to create environmental friendly and
energy efficient buildings. It entails actively
harnessing renewable natural resources like
solar energy and utilizing materials that cause
the least possible damage to the global
commons—water, soil, forests & air.
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Energy resource efficiency in new
constructions can be effected by adopting an
integrated approach to the building design.
The primary steps in this approach are listed
below :
1.Incorporate solar passive techniques in a
building to minimize load on conventional
systems (heating, cooling, ventilation &
lighting).
2.Design energy efficient lighting and HVAC
(heating, ventilation, and air conditioning)
systems.
3.Use renewable energy systems (solar
photovoltaic systems/ solar water heating
systems) to meet a part of building load.
4.Use low energy materials and methods of
construction and reduce transportation
energy.
The dark colors on the thermo gram of a
Passive house (right) show how little heat is
escaping compared to a traditional building
(left)
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Energy efficient construction
techniques
1. Solar Chimney: A solar chimney often
referred to as thermal chimney is a way of
improving the natural ventilation of
buildings by using convection of air heated
by passive solar energy. A simple
description of a solar chimney is that of a
vertical shaft utilizing solar energy to
enhance the natural stack ventilation
through a building.
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The use of a solar chimney may benefit natural ventilation and passive cooling strategies of
buildings thus help reduce energy use, CO2 emissions and pollution in general. Potential benefits
regarding natural ventilation and use of solar chimneys are:
1. Improved ventilation rates on still, hot days
2.Improved control of air flow through the building
3.Improved air quality and reduced noise levels in urban areas
4.Increased night time ventilation rates
5.Allow ventilation rates of narrow, small spaces with minimal exposure to external elements
6.Improved cooling during warm seasons
7.Improved thermal comfort (improved air flow controls, reduced draughts)
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2. Wind catcher: A wind catcher is a traditional Persian architectural device used for many
centuries to create natural ventilation in buildings.
The wind catcher functions on several principles:
First, a wind catcher is capped and has several directional ports at the top (Traditionally four). By
closing all but the one facing away from the incoming wind, air is drawn upwards using the, similar
to how opening the one facing the wind would push air down the shaft. This generates significant
cooling ventilation within the structure below.
In a windless environment or waterless house, a wind catcher functions as a stack effect
aggregator of hot air. It creates a pressure gradient which allows less dense hot air to travel
upwards and escape out the top. This is also compounded significantly by the day-night cycle
mentioned above, trapping cool air below. The temperature in such an environment can't drop
below the nightly low temperature.
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3. Trombe Wall: A Trombe wall is a sun-facing
wall built from material that can act as a
thermal mass (such as stone, concrete, or
water tanks), combined with an air space,
insulated glazing and vents to form a large
solar thermal collector
Passive solar design using an
unvented trombe wall and summer
shading
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Modern Trombe walls have vents added to the top
and bottom of the air gap between the glazing
and the thermal mass. Heated air flows via
convection into the building interior. The vents
have one-way flaps which prevent convection at
night, thereby making heat flow strongly
directional. This kind of design is an isolated
passive thermal collector. By moving the heat
away from the collection surface, it greatly
reduces thermal losses at night and improves
overall heat gain.
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‘Hues of Life’
kakkanadu, kochi
Good Earth “Hues of Life” is a tropical high
rise apartment building, a green alternative
which responds to and takes advantage of
the climate and the location.
Designed to accommodate 31 apartments with
sky gardens, “Hues” is Good Earth’s foray
into bio-climatic skyscrapers.
Details:
1. 3 bedroom—20 units(2380 sq ft)
2. 3 bedroom—11 units(2080 sq ft)
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Highlights
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Sky-gardens in individual homes
Sky courts at intermediate levels as community spaces
Service core as a buffer area
The view exploited from all spaces.
Tropical landscape in the sky gardens and courts
Ground floor semi- open, connected to the outside
Air spaces and wind scoops
Continuous natural ventilation
Use of cavity walls for insulation
Natural day lighting, even in the deeper parts of the building
Use of natural materials
Sun and rain protection to the building by the provision of large recesses, for windows and
openings.
• Reduced use of water and power resources. Lower operational costs
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Interesting features
1. The individual sky garden: These are ‘green
terraces’ with a breathtaking view in each apartment.
The design of sky gardens minimize the heat &
moisture on the lower flower, by virtue of protecting
the wall below.
They are staggered on the alternate floors which
enhance the air movement between the floors. It also
acts as the buffer from dust, heat and lashing rain.
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2. The community sky court: The sky court is
a landscaped terrace designed in the
transition areas around staircases and
lifts, at intermediate levels, to act as a
community space, and as visual relief.
A space for children to play, neighbors to
meet, plants and lawn giving the air a
fresher feel. The sky court is designed to
integrate hard and soft landscape, to
create a variety of areas which encourage
interaction among different groups.
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Wind scoop & natural light
The atria created by the sky court, act as wind scoops, drawing fresh air into them, and allowing
hot air to escape, even through the homes. The same can be said for natural light, which
penetrates to the deepest area of the building through them.
natural ventilation
Large openings have been provided on the windward and leeward sides, within the apartments, and
cross ventilation is taken care of through the air spaces in the sky courts. The sky gardens in the
apartments create air currents, drawing air into the house.
the service core
The service core is located on the south side of the building, and thus acts as the buffer from the
heat, keeping the maximum heat gain away from the user space.
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Natural materials and cavity
walls
For creating energy efficient and thermally
comfortable spaces, a combination of hollow
terracotta blocks and semi wire cur bricks
have been used, for the external walls.
This forms a wall with three air cavities, the
terracotta blocks on the outside and the
bricks on the inside, keeping the interiors cool
and bringing down the use of air-conditioning.
Besides serving as a passive coolant, the
external wall is also very low on maintenance,
bringing down the long term maintenance
costs of the building.
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References
1. Energy-efficient buildings in India—Tata Energy Research Institute (TERI)
2. http://en.wikipedia.org/wiki/Image:Green_City.jpg
3. http://www.goodearthhomes.net/HuesOfLife.html
4. http://en.wikipedia.org/wiki/Image:Passivhaus_thermogram_gedaemmt_ ungedaemmt.png
5. http://en.wikipedia.org/wiki/Sustainable_architecture
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