2. A Proposed Bioclimatic Design of a Hotel Building
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BIOCLIMATIC ARCHITECTURE
Climate Responsive Design: A Sustainable Approach
“Climate is clearly one of the prime factors in culture, and therefore in built-form. It is the mainspring
for all the sensual qualities that add up to a vital tropical architecture”, Tan Hock Beng.
Climate responsive design is based on the way a building form and structure moderates the climate
for human good and well-being. The thrust of this design (climate responsive) direction is to utilize
concepts that minimize environmental impacts of buildings through selecting an appropriate design
strategy in response to the climate.1It requires both analytical and synthesis skills to optimize the
relationship between the site, climate and briefing requirements.
Bioclimatic Design is in line with the climate responsive design only that it starts with an analysis
of the climate and then moves to the design synthesis focusing on which particular strategies analyzed
by the bioclimatic charts to meet the design objectives of the study.2These strategies are basic
directions that can be taken with regard to optimum climatic performance of the building.
According to the studies conducted in the US concerning on the environment, mainly about 40% of
the greenhouse gas emissions (CO2) came from building sector rather than from the transportation
sector. This was the end result of buildings that uses non-renewable sources of energy for cooling and
lighting. With the increasing concern for environmental impacts of buildings and the quality of their
internal environment this has raised the debate as to the role architects should play in the
environmental design of buildings. This conference was strongly urged since the government had seen
what has become of our resources that were no longer enough for the next generations to come.
1(Hyde, 2000)
2(Hyde, 2000)
3. A Proposed Bioclimatic Design of a Hotel Building
The main argument here is that ‘true architecture’ has failed to link resources with design and
consequently with environmental impact. Thus, the first major axiom of Green design is concerned with
resource utilization. Second is the profligate use of resources for purely conceptual and aesthetic
purposes, and ore focus on architecture that is more holistically orientated to its environmental role.
Clearly this represents a paradigm of thinking concerning design and requires a philosophical and ethical
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commitment from the designer.3
The Royal Australian Institute of Architects (RAIA) has developed the following environmental principles
that are given importance in Architecture:
o Maintain and, where it has been disturbed, restore biodiversity.
o Minimize the consumption of resources, especially non-renewable resources.
o Minimize pollution of soil, air, and water.
o Maximize the health, safety and comfort of building users.
o Increase awareness of environmental issues.
Climate responsive design is therefore an integral part of the environmental framework that is bei ng
developed to reduce environmental impacts and provide for human well -being.
3(Hyde, 2000)
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Bioclimatic Architecture
Bioclimatic architecture refers to the design of buildings and spaces based on the scientific
assessment of the local climate, aimed at providing thermal and visual comfort to the users and making
use of the natural sources. Its basic elements of bioclimatic design are passive solar and cooling systems
which are incorporated onto buildings.4
This term, bioclimatic refers to the relationship between climate and architecture. This comes
from the word “bioclimatology”, the study of the effects of climatic conditions on the living organisms.
It has a long pedigree going back to the work of Le Corbusier with his use in hot climates of ventilati ng
atria, solar screening and thermal mass.
The design process integrates principles of human physiology, climatology and building physics
by considering design components such as: climate types and requirements; adaptive thermal comfort;
vernacular and contextual solutions; microclimate: sun path, wind and rain; and working with the
elements, such as passive and active systems, and development of a responsive form.
In addition, the following principles have been proposed to redefine the previous ones:
• creating user health and well-being;
• using passive systems;
• restoring ecological value;
• utilizing renewable energy; and
• Applying life-cycle thinking, assessment and costing.
The built form itself is regarded as essentially an enclosure erected to offer protection to the
humans and their related activities over the external environment with an improved level of internal
comfort conditions. If its conformity to the passive-mode design is not taken into consideration then as
a consequence more energy resources may have to be used in its Mechanical and Electrical systems to
compensate for such errors. It should be taken note that this approach is not to design architectural
forms to against the climate of the locality, but rather as a response to it.
4(CRES, 1987)
5. A Proposed Bioclimatic Design of a Hotel Building
Arch’t. Ken Yeang even cited in his book, Ecodesign (2006) that one of the primary objectives in
the passive design as a low-energy design is not achieved by electro-mechanical means, but by the
buildings particular morphological organization.5The design process is on the building configuration and
built-form of the building in response to its climate. Other considerable aspects influencing the
configuration of the building and its built form are its spatial arrangements and layout, the
implementation of passive-mode designs in the structure, and the maximization of views in the building
with the outside environment.
It is only in this sense that the morphological form and organization of the building can be
achieved through the assessment of the locale’s climate by the use of the bioclimatic charts which will
be discussed later on this article.
Modernism drew inspiration from vernacular climatic practices whether in hot or cold regions.
Climate is currently emerging as a new force in sustainable design- whether it is concerned over
mitigating the effects of climate change or by actively engaging in climate responsive
design.Understanding climate within and around buildings offers the chance to remodel practice and
save energy and water.
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5(Yeang, Ecodesign: A Manual for Ecological Design, 2006)
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Design Performance Measures
The performance measures used during the design stage vary with the strategies used. If the
building is free running using primarily passive systems then it is appropriate to use thermal comfort as
the main indicator of performance. Where it uses active systems then the mechanical systems provide
thermal comfort, in this case the main indicator is energy use.
1.1. Thermal Comfort
Comfort can be defined as the complete physical and mental well-being. Thermal comfort is a subset
of the broad definitions of comfort and relates to human and environmental factors. It is a complex area
of study in fundamental terms, but for the designer the key issues relate to the building and
environmental factors that affect comfort since these are amenable to manipulation in the design of the
building.6 The main environmental factors affecting thermal comfort are as follows:
a. Air temperature
b. Radiation
c. Air velocity and air movement
d. Humidity levels
Research has pointed out that basic physiological response to thermal comfort is moderated by
acclimatization to respective climate conditions, thus people living in temperate climates may have a
different sensation of climate to that of people living in the tropical climates. The person-specific nature
of comfort means that defining precise levels of comfort of buildings is fraught with difficulty.
The level of internal comfort conditions in a building depends on the acceptable internal condition of
the users. Comfort zones are usually between 180C (650F) and 240C (750F), but this varies depending on
the relative humidity, which should remain between 30 and 65 per cent. Relatively humidity is a
measure of the amount of water vapor in the air, 100 per cent being saturated air. Within the above
general limit the higher the relative humidly becomes the lower the air temperature needs to be in
order for humans to feel comfortable. 7
6(Hyde, 2000)
7(Yeang, Ecodesign: A Manual for Ecological Design, 2006)
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There are two types comfort conditions a human body can adapt:
a. Optimal conditions
This type of interior climate - “latent physical heat regulation” is not perceived by the
vegetative nervous system, that is, by human sense but by the autonomous nervous system
alone. The body automatically adapts to the interior climate easily without human senses.
Optimal values for room temperature lie between 22-260C which would belong to the
comfort limit of Cebuano that is if there is only slight air movement of up to 0.3 m/s then this
would be comfortable. If temperatures might raise then ai r movement should be directly
proportional to our temperature meaning to say that a rise in temperature would mean a rise in
our air velocities say up to 0.8 m/s for optimal conditions with a humidity factor of 20-90%.
b. Tolerable conditions
This type of interior climate – “the sensible regulation of heat” which is controlled by
the vegetative nervous system and therefore consciously registered by humans, first takes over
when the climate differs from the optimal values. This type of interior climate is permissible as
long as the health of human beings is not seriously affected or endangered.
In this case almost still air in warm climatic zones, temperatures of up to around 300C
can be regarded as tolerable. In such a case that air humidity, in addition to air movement, also
has a significant influence on our sensitivity to the interior climate.
With our climate conditions as having high humidity levels the approach is either to
increase our temperature or to lower our indoor temperature and increase air movement within
interiors to achieve a cooling sensation for the comfort of humans through the evaporation of
sweat from the skin.
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1.2. Energy Performance
With the increased concern for energy use, arguments have been developed to assist with the
saving of energy use through life-cycle costing. In principle this involves the computation of both the
capital cost of the building and the cost of operating the building over its proje cted life. The energy costs
often exceed the capital costs of the building over time, this condition has focused design efforts to
reduce the need for and use of active system.
Often the cost of plant and equipment is around 40% of the capital cost of a complex building
and therefore strategies that can reduce the demand for this type of equipment will reduce capital
costs. In addition the need to save operational energy in the running of active systems have focused
attention on the design decisions that contribute to energy saving.
The first important way to save energy is to use less of it, to the first goal is to cut demand, and
second goal is to supply power in a manner that is benign (use of renewable energy sources) and
efficient as possible. It is at this stage that the brief can be questioned with regard to power
requirements. Butwith Bioclimatic approach the design does not focus much on these active systems
rather on the passive ways through its built form and orientation of the building that can provide the
optimum design to reduce energy use. 8
With the application of these strategies, the designer can then on move to the mixed mode
approach of the building wherein selected active systems are used inside the building for energy
efficiency. These active systems are needed for the building in order to cater to the days wherein the
climate is unsuitable to the thermal comfort of humans. Table. 2.0. Shows the efficiency measures for
the demand and supply of energy in buildings. The demand side (Passive-mode design) is based on the
bioclimatic principles of Arch’t. Ken Yeang in his Eco design Book.
8(Yeang, Ecodesign: A Manual for Ecological Design, 2006)
9. A Proposed Bioclimatic Design of a Hotel Building
Table 2. Efficiency measures that can be used in the demand and supply of energy in buildings.
Demand Side (Passive-Mode Design) Supply Side (Active-Mode Design)
-Built-form configuration and site layout planning
- Built-form orientation
-Enclosural Design
-Solar Control Devices
-Passive Daylight Concepts
-Wind & Natural ventilation
-Roofscape
-Built-from envelope colour
-Landscaping
-Passive cooling systems
-Building mass
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-On site generation
-Integrated PV systems
-Alternative generation
-Gas fuel cells
-Thermal energy storage
-Ice storage
-User control
1.3. Visual Comfort
In achieving an acceptable comfort level of daylight, one of the main ‘discomforts’ to be
recognized and resolved is the problem associated with glare (both direct and indirect). Treatment of
this problem reflects a lighting strategy and has implications for the energy performance of the building.
Glare is a function of contrast and brightness and results from one of two causes. In the first, a bright
light source (such as a sunlit window) or a bright lamp) is viewed from a surrounding area that is in
relative darkness. In this case, glare results from excessive contrast and can be relieved by increasing
brightness of the surroundings. This type of glare causes discomfort to occupants, resulting in poor
visual performance and potential dissatisfaction with the visual environment. Second, if the space is
over lit by a source that is so excessively bright that the eye mechanism becomes saturated, the result is
“disability glare”.
Lighting is required for functional purposes in the building to enable the comple tion of visual
tasks and for human safety. The principles for satisfying these requirements are climate dependent. The
climate dependent issues come from the quality and quantity of day lighting found in the different
climates. This in turn is related to the sky conditions and the level of solar radiation, which vary in the
different types of warm climate.
10. A Proposed Bioclimatic Design of a Hotel Building
Hot humid climates are fairly cloudy during the year, with 60-90% cover. Illuminance from the
clear sky is high but is reduced with overcast conditions to approximately 12% of the clear sky
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conditions.9
Solar radiation is less than that for the hot dry and moderate climates. The high humidity causes
a reduction in the transparency of the atmosphere, leading to lower solar radiation. The clear sky
conditions in both the moderate and hot dry climates have high light levels and solar radiation. 10
Table 3. Typical lighting levels and solar radiation for warm climates (Hyde, 2000)
Hot Humid Hot Dry Moderate
Typical sky luminance, lumens
Clear skies 7500 10800 100000
Overcast, obscured 9000 9000 20000
Typical solar radiation, W M2
Clear skies 750 1080 1000
Overcast 90 90 200
It is clear from Table 3.0 that there is ample daylight for interior lighting but even though the
Solar radiation in hot humid climates have a lower value it can still contribute to the heating of the
building in which we designers should avoid this as much as possible.
Lighting can be separated into both electrical and daylight. A further distinction should also be
given with regard to sunlight and diffuse light. Day lighting can contain both sunlight and diffuse light.
Diffused light is the indirect light that is light reflected from external surfaces, whereas sunlight is the
direct light from a clear sky. The main concern with day lighting in warm climates is that the access of
sunlight into the building brings heat and ultraviolet light.
9(Hyde, 2000)
10(Hyde, 2000)
11. A Proposed Bioclimatic Design of a Hotel Building
The use of glass traps the heat by virtue of the greenhouse effect and thus contributes to the
heat load. Diffuse light on the other hand, is more benign; it has a much lower component of
heat.Hence, the need to shade openings to reduce the direct solar access and increase the amount of
diffused light. Yet this simple strategy represents a high degree of complexity, which centers on the
performance requirements and design strategies for windows and on the shading devices used.
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Design Issues concerned with Visual Comfort:
1. Diffuse Light:the use of diffuse light where possible, rather than direct sunlight, to avoid heat
gain and ultraviolet degradation of interior materials and furnishings.
2. Heat gain from glazing: the provision of external shading to reduce direct solar gain but allow
sufficient lighting for natural lighting; optimize the glazing ratio to provide appropriate natural
lighting conditions, and provide ventilation to remove the heat gain associated with glazed
areas.
3. Glare: use materials and colors to avoid high contrast in the external and internal lighting
conditions; elements such as landscaping, tinted glass, and screens are of use as buffers to
moderate internal and external conditions.
4. Light transitions and thresholds: in situation where contrasts occur, avoid sharp contrast in light
levels to avoid disabling glare; set of electrical lighting threshold for smooth transitions from
natural light. 11
11(Hyde, 2000)
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Passive Mode Methods
“Climate is clearly one of the prime factors in culture, and therefore in built-form. It is the mainspring
for all the sensual qualities that add up to a vital tropical architecture”
Tan Hock Beng.
Climate responsive design is based on the way a building form and structure moderates the climate
for human good and well-being. The thrust of this design (climate responsive) direction is to utilize
concepts that minimize environmental impacts of buildings through selecting an appropriate design
strategy in response to the climate.12It requires both analytical and synthesis skills to optimize the
relationship between the site, climate and briefing requirements.
In the Book Ecodesign: A Manual for Ecological Design by Architect Ken Yeang, outlines five basic
modes for designing suitable internal comfort conditions in the built environment: passive mode, mixed
mode, full mode, productive mode, and the composite mode. Essentially, the passive mode produces
improved internal comfort conditions without the use of nay non-renewable sources of energy. The
main reason for this mode prior to adopting any of the other modes is that such strategy uses up
relatively little or zero non-renewable energy and so has the least impact on the environment.
“Passive-mode design is, in effect, bioclimatic design and requires an understanding of the climate of
the locality to enable advantage to be taken of the ambient energies and climatic characteristics.”
Ken Yeang (2006)
Passive-mode systems provide internal comfort by using natural energy sources and sinks. These
energy flows are by natural means through radiation, conduction, and convection with no use of
mechanical means. These vary from one climate to the other and with our location here in the
Southeast Asia specifically near the equator we need to reduce solar gains and maximize natural
ventilation.
12(Hyde, 2000)
13. A Proposed Bioclimatic Design of a Hotel Building
The built form itself might be regarded here as essentially an enclosure erected to offer protection
to some human-related activity over the external environment with an improved level of internal
comfort conditions. If the designer does not optimize all these passive-mode aspects to the built form
then the result may be erroneously shaped or inappropriately oriented built-form. In consequences,
more energy resources may have to be used in its M&E systems to compensate for such errors, which
make nonsense of any attempt at a low-energy design.
The approach is not to design architectural forms to follow the climate of the locality, but rather as a
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response to it. Climate does not determine built form but it does influence it.
“Architectural Design plays a vital role in Architecture of a given place. According to the
Theories in Architecture, It is influenced mainly on two factors namely the General influences (needs of
man) and influences of Nature (Climate and Topography) Climate affects the habits and temperaments of
people thus creating suitable spaces for comfort is an essential matter for protection against the external
conditions of the outside environment and making use of its natural factors ”.
George H. Salvan
The following are some of the passive methods to be applied to the built form to address any
remaining needs for a higher level of internal comfort conditions; these may be met by active or mixed
mode systems powered by ecologic ally sustainable forms of energy.
Built-form configuration, orientation and site layout planning
Enclosural (and façade) Design
Passive Daylight Concepts
Wind and Natural Ventilation
Roofscape
Built from envelope color
Landscaping
Passive Cooling Systems
Building Mass and Form
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1.1. Built-form configuration, orientation and site layout planning
In this method, the built form, its spatial arrangements and layout are configured and planned
in relation to the energies of the ambient environment and the meteorological data of the locality as a
passive response. The building form needs to be shaped and laid out on the site to function in a low-energy
as with other design intentions such as to capture the site’s wonderful views, and to achieve
privacy or security. Reducing the heating energy requirements is influenced by its form, orientation in
the site, and its ratio of volume to surface.
Generally, the built form for climatic zones near the equatorial zone should have a ratio of 1:2 or
1:3 length ratio. For Tropical zones, 1:3 length ratio is appropriate. Another important design
consideration is the service core placements or the building’s utilities, buildings in the tropics should be
arranged longitudinally from east to west. Fig. 13 shows a strategic planning of room orientations in hot
humid climates.
Fig. 13. Planning strategies in Hot Humid Climates
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1.2. Enclosural (and facade) design
The façade and Enclosural design should be given priority over the built form’s contents
and should in effect be designed in combination with the optimization of the passive systems,
mixed mode and such active systems as are used. The permeability of the skin of the building to
light, heat and air, and its visual transparency must be controllable and capable of modification,
so that the building can react to changing local climatic conditions.
These variables include solar screening, glare protection, temporary thermal protection
and adjustable natural ventilation options. A well designed building envelope will yield
significant energy savings. The building’s façade, as our third skin right after our clothes & skin,
needs to breathe and to function as a regulator, protector, insulator, and integrator with the
natural environment.
The external wall having direct solar insolation should be insulated and the ‘time lag’
taken into consideration of the building materials used. In hot humid climates, it is necessary to
use materials with high thermal lag. Thermal lag is the ability of a material through its mass to
delay the passage of heat from one surface to the other. Fig. 14.0 shows the time lag materials
that are commonly used here in the Philippines.
Material Time Lag
100mm thick Adobe 3 to 4 hours
150mm Precast Concrete 4 hours
25mm thick Gypsum 1 hour
25mm thick Limestone 1 hour
12mm Plywood ½ hour (30 minutes)
6mm Plywood ¼ hour (15 minutes)
20mm V-Cut Wood Siding 1.5 hours
100mm thick Concrete
3 to 4 hours
Hollow Block
Table 4.0. Thermal Lag of Materials
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1.3. Solar-control devices
Sun shading is a building component, which functions is shading device to the building
fabric to avoid he direct sun radiation to the building. In many studies that have implemented
sun shading devices into their buildings have significant savings in terms of energy efficiency.
These devices not only protect the building’s skin from heating up but also provide visual
comfort in the sense that it can easily adjust the brightness of the outside environment.
Studies from Institute of Technology Bandung in Jakarta have clearly modified some
concepts in the choosing of the sun shading devices appropriate for a particular building type.
They have emphasized that in the selection of sun shading devices should not mainly focus on
its functionality in terms of its location. These devices should also be evaluated in terms of their
efficiency, construction, cost and maintenance. Table 5.0 shows the percentage (%) reduction of
heat transfer for the sun shading device used.
But before selecting which shading devices are to be adapted an understanding of the
solar geometry of the locality as the basis for determining the angles of the cross -section of the
solar shading devices to be used for the façade is essential.. Generally, on the hot sides of the
built-form, regardless of latitude some form of solar shading is required making due allowances
for glare and the quality of light entering the spaces.
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1.4. Passive daylight concepts
The issue on glare has affected the acceptable comfort level of daylight for the users;
these are both direct and indirect glare. Treatment to this problem reflects a lighting strategy
and has implications for the energy performance of the building. Glare is a function of contrast
and brightness and results from one of two causes: a bright light source from a dark space and
from an over-lit space. These result in visual discomfort to the users in which could cause health
problems.
Passive mode includes the use of passive-daylight devices or techniques. The objective
in the bioclimatic design is to maximize the use of day lighting and to decrease the need more
energy-consuming artificial lighting. Most passive-daylight techniques have worked to control
the incoming direct sunlight in order to minimize its potentially negative effect on visual
comfort, such as glare, and reduce the building’s cooling load by reducing the heat gain to the
building.
Direct sunlight is an excellent interior illuminant if it is intercepted at the plane of
aperture and efficiently distributed throughout the building without glare. These traditional
daylight designs can provide adequate daylight within about 4.5 meters of conventional height
windows. The use of larger windows and higher transmittance glazing to provide sufficient levels
of daylight at distances further from the window has proved to be ineffective since daylight
levels decrease as the distance furthers from the window.
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1.5. Wind and Natural Ventilation
Natural ventilation may be used to increase comfort (air movement), for health or for
building cooling. Natural means of ventilation utilize the motive force of air pressure
differentials from external wind effects on the building, and from temperature dif ferentials. It
ensures fresh air supply to the interiors however it must be taken into account that this could
create dustier or noisier internal conditions especially at the lower levels of the high rise.
Properly designed natural ventilation solutions can result in both capital cost and energy
savings. In addition, it is also desirable to minimize the requirement for mechanical ventilation
and air-conditioning systems in order to ensure a ‘healthy’ building. In addition, maintenance is
reduced, there are fewer incidents of the ‘sick building syndrome’ and there is a reduction in
carbon dioxide emissions.
Ventilation can improve comfort by increasing the indoor air speed in interiors to make
the occupants feel cooler. The logical reason for this is that this increases the rate of sweat
evaporation from the user’s skin leaving a cooling sensation as a result.
The natural ventilation in buildings is encouraged by the provision of low-level inlets and
high level exhaust openings that allow fresh air to be drawn in and foul air to be expelled. The
use of stack ventilation and wing walls are also a helpful technique in the passive cooling
systems of the buildings. These systems help induce internal air movement inside the building
while expelling the hot air inside the building through the law of buoyancy.
To understand more on how to appropriately ventilate the building one should
understand first the principles of air movement and consider the average interior air velocity to
know how much wind speed is induced in the interiors. (Fig. 15.0)
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Fig. 15.0. Average interior air velocity
Principles of Air movement:
1) Air is created by differentials. Air flows from a high pressure to a low pressure area.
2) Air possesses inertia.
3) Air flows through the path of least resistance.
4) Air movement is affected by directional changes.
5) Optimum airflow is relative to size of openings.
6) Air velocity is dependent to inlet-outlet ratio.
7) The airflow pattern is dependent to opening locations. Studies have shown that
significant air movement is achieved by a skewed positioning of window openings.
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1.6. Roofscape
The roof system should be considered as the fifth façade of the building. This should be
thermally insulated to avoid the penetration of heat inside the building creating spaces of
discomfort. In tropical countries, the construction of roofing cost more initially with its
overhangs protecting the building envelope giving it shade.
This type of system is only applicable to low-rise buildings than medium to high rise
buildings. Most of these buildings usually leave the roof top open to the outside environment
constructed in concrete surfaces however, this type of construction can still add up to the
heating of the building and at the same time leaves the space open for no use at all except for
the placement of utilities.
One of the studies in the US, have
shown that vegetated roofing systems offer
good thermal insulation levels than the
conventional roof deck systems.
Vegetated roofs offer a variety of
benefits for the building fabric, not only
does it offer good thermal insulation levels
but can also be used for planting plants,
trees, and even vegetables. Plus, they also
offer good verandas in the sky for a 3600
view of the outside environment increasing
the environmental awareness of every
person.
Fig. 17.0. Thermal Insulation Capacities for roofing systems
21. A Proposed Bioclimatic Design of a Hotel Building
Table 6.0 Greenery of buildings and its surroundings will provide the following benefits
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Environmental Benefit
-reduce surface and ambient temperatures
-Improve air quality
-balances the water cycle
Social Benefit
-comfortable and relaxing spaces for gatherings and
activities
Aesthetic Benefit -Visually appealing and soothing to the eye
Economic Benefit
-savings from air purification
-energy savings from cooling buildings
-increase property value
-recycling water
1.7. Built-form envelope color
Peak cooling can be reduced by as much as 40 percent by using white or lighter-colored
materials, especially for the roof surfaces. Similarly, improvements can be achieved by placing
vegetation around buildings. Both methods are efficient for the reduction of energy demand by
the minimization of the urban heat island effect and by boosting the urban temperatures from
the reflection of the sun’s rays from pavements and building surfaces.
An effective protection against radiation impact for the external wall is the selective
absorption and emission characteristics of certain materials, especially under hot conditions.
Materials which reflect rather than absorb radiation bring about lower temperatures within the
building. Table 6.0 shows the solar absorption and emittance rate of some selected materials.
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Table 7.0 Solar absorption and emittances of Selected Materials
Item Emittance Rate Absorptance Rate
Black non-metallic surfaces such as
0.90-0.98 0.85-0.98
asphalt, carbon, slate, paint
Red brick and tile, concrete and stone,
rusty steel and iron, dark paints
0.85-0.95 0.65-0.80
Yellow and buff brick and stone,
firebrick, fireclay
0.85-0.95 0.50-0.70
White or light-cream brick, tile, paint
or paper, plaster, whitewash
0.85-0.95 0.30-0.50
Bright aluminum paint, gilt, or bronze
paint
0.40-0.60 0.30-0.50
Polished brass, copper, monel metal 0.02-0.05 0.30-0.50
1.8.Landscaping
One of Ken Yeang’s environmental vision is the incorporation of organic elements with
our inorganic structures (buildings) this would involve in the integration of vertical landscaping
in buildings to help restore the biodiversity of the site. The transpiration of water by plants helps
to control and regulate the relative humidity and temperature of the site. Not only do they help
regulate the microclimate setting of the site but also adds up to the cleaning of the outside
pollutants in the air we breathe.
Recessed terraces or ‘sky courts’ serve as interstitial zones between the inside areas and
the outside areas. These are parks-in-the-city, the balancing of the inorganic mass of the
building’s hardware and components with the organic mass to give a more balanced ecosystem.
This useful device serves the following functions: as emergency evacuation zones; areas for
planting and landscaping; for future expansions; plus they also serve transitional spaces from
the inside to the outside environment connecting man with nature. This will then enable man to
experience the external environment directly to enjoy views with the natural surroundings of
the site.
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1.9.Building Mass & Form
Buildings are designed as thermal systems, constructed with materials that have their
own qualities of thermal inertia in combination with spaces that permit and generate natural
flow of air in, out, around and through the building, providing for the modif ication of
temperature and speed, ventilation and cooling, without mechanical assistance. The form and
elements of a built form can be made to respond natural cycles both daily and seasonally and to
exploit ambient energy sources. This can be achieved through the joint spatial and temporal
interactions in natural and human-made environments, which combines the interactions of
space dimensions, the size and shape of an open or enclosed space, to produce an effect.
As mentioned earlier, if a built form is designed to optimize all the passive-mode
options for the built form to remain acceptably comfortable to its occupants even in the event
of power failure supplied from any electromechanical systems.
To be able to know which strategy to use in the building mass and form, one needs to
first assess the climate data of the locality in terms of its dry and wet bulb temperatures as well
as its humidity factor. This is usually in the psychrometric charts from near weather stations to
be assessed in the bioclimatic analysis by the using of the bioclimatic charts.
These charts facilitate the analysis of the climate characteristics of a givenlocation from
the viewpoint of human comfort, as they present, on a psychrometric chart, the concurrent
combination of temperature and humidity at any given time. They can also specify building
design guidelines to maximize indoor comfort conditions when the building's interior is not
mechanically conditioned. All such charts are structured around, and refer to, the 'comfort
zone'. The comfort zone is defined as the range of climatic conditions.
The bioclimatic chart shows the relationship of the four major climate variables that
determine human comfort. By plotting temperature and relative humidity, one can determine if
the resulting condition is comfortable (within the comfort zone), or too hot (above the top of
the comfort zone, or too cold (below the bottom of the comfort zone).