Page 55 - GRIHA Manual Volume II - Introduction to National Rating System
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Sustainable site planning 47
Site inventory characteristic 03 – Solar access
1. Building In order to reduce dependency on energy intensive Location of Features such as solar ponds can help store the radiant
position for systems for lighting and ventilation, buildings must be energy-eficient energy of the sun as heat, in a manner as to be able to
daylighting, planned in a manner as to allow maximum ingress of features such use it for various applications such hot-water generation
natural light and permit natural ventilation as far as as solar pond and electricity generation. Such features are also
possible in all occupied spaces. Daylighting can be most effective if they are located at a part of the site
maximized with an optimal visible sky component (SC) in where they encounter minimum obstruction from other
all occupied spaces. This is possible only if the windows buildings and natural elements on the site. The clearer
opening into the occupied spaces are free of any their view of the sky, the more they are likely to receive
obstructions that may block a clear view of the sky from as direct solar radiation and the more shall be the stored
them. This also includes adjacent buildings, trees, and heat in them. Thus, such features must be located on
other elements. Under ideal conditions, the lowest loor the site in a careful manner so as to ensure no shadows
windows should subtend an angle not greater than 22.5 or obstructions during installation as well as over their
degrees with the top of an adjacent building/object. This entire life cycle.
angle also ensures an ideal distance for sound natural
ventilation.
2. For positioning solar photovoltaic panels for generation Placement As is clear from the National Building Code 2005
Photovoltaics of energy on-site, it is imperative that a shadow-free of selective (Part 8 building services, Section 01 – Lighting and
area be identiied with an orientation appropriate for species of Ventilation, Table 3 – Direct and diffused solar radiation
optimal generation and eficiency of the solar panel. It is trees (such values for various orientations) some parts of a building
determined as a rule of thumb that the ideal orientation as deciduous façade need to be protected from the harsh glare of
for optimal performance of a solar cell is at an angle trees on the direct sunlight and other parts need to be shaded
equivalent to the latitude of the place where it is being south of the only seasonally. Among the most economical ways
installed. site) of doing this is by an appropriate planting/landscape
design strategy that identiies speciic trees for speciic
orientations. Deciduous trees planted on the south
side can ensure that the building spaces are shaded
through the harsh summers, but get adequate sunlight
for passive heating during winters when they shed their
leaves. Similarly, having evergreen trees on the east
and west façade can ensure glare-free natural lighting in
the spaces in a particular orientation of the building.
3. Solar Architectural design interventions can signiicantly
passive impact a building’s energy requirement. Features such
techniques as Window to wall ratio (the ratio of the total glazed/
window area to the entire wall area in that speciic
orientation), solar chimneys, attached sun spaces,
trombe walls, and so on, are extremely site-speciic
and must be located on orientations of the building that
complement the local site conditions. Passive heating
features should be located such that they absorb
maximum solar radiation though the day.
4. The height and distance of walls from a building can
Construction impact and inluence the ability of the building to exploit
of walls natural light and ventilation. Often it is observed that site
boundary walls are built up to 3 metres or 4.5 metres.
As mentioned earlier, impermeable obstructions such
as solid walls can create wind-shadow areas up to a
distance equivalent to 8–10 times the height of the wall.
This can seriously compromise the uniformity of wind
pressure and natural ventilation on the building site.
When the winds converge back on to the ground they
tend to create eddies that can further give rise to pockets
of high/low wind pressure. This further impacts the
comfort of the people on the site. So walls must be built
taking into account the likelihood of its impact on the site
and its surrounding areas.
Site inventory characteristic 03 – Solar access
1. Building In order to reduce dependency on energy intensive Location of Features such as solar ponds can help store the radiant
position for systems for lighting and ventilation, buildings must be energy-eficient energy of the sun as heat, in a manner as to be able to
daylighting, planned in a manner as to allow maximum ingress of features such use it for various applications such hot-water generation
natural light and permit natural ventilation as far as as solar pond and electricity generation. Such features are also
possible in all occupied spaces. Daylighting can be most effective if they are located at a part of the site
maximized with an optimal visible sky component (SC) in where they encounter minimum obstruction from other
all occupied spaces. This is possible only if the windows buildings and natural elements on the site. The clearer
opening into the occupied spaces are free of any their view of the sky, the more they are likely to receive
obstructions that may block a clear view of the sky from as direct solar radiation and the more shall be the stored
them. This also includes adjacent buildings, trees, and heat in them. Thus, such features must be located on
other elements. Under ideal conditions, the lowest loor the site in a careful manner so as to ensure no shadows
windows should subtend an angle not greater than 22.5 or obstructions during installation as well as over their
degrees with the top of an adjacent building/object. This entire life cycle.
angle also ensures an ideal distance for sound natural
ventilation.
2. For positioning solar photovoltaic panels for generation Placement As is clear from the National Building Code 2005
Photovoltaics of energy on-site, it is imperative that a shadow-free of selective (Part 8 building services, Section 01 – Lighting and
area be identiied with an orientation appropriate for species of Ventilation, Table 3 – Direct and diffused solar radiation
optimal generation and eficiency of the solar panel. It is trees (such values for various orientations) some parts of a building
determined as a rule of thumb that the ideal orientation as deciduous façade need to be protected from the harsh glare of
for optimal performance of a solar cell is at an angle trees on the direct sunlight and other parts need to be shaded
equivalent to the latitude of the place where it is being south of the only seasonally. Among the most economical ways
installed. site) of doing this is by an appropriate planting/landscape
design strategy that identiies speciic trees for speciic
orientations. Deciduous trees planted on the south
side can ensure that the building spaces are shaded
through the harsh summers, but get adequate sunlight
for passive heating during winters when they shed their
leaves. Similarly, having evergreen trees on the east
and west façade can ensure glare-free natural lighting in
the spaces in a particular orientation of the building.
3. Solar Architectural design interventions can signiicantly
passive impact a building’s energy requirement. Features such
techniques as Window to wall ratio (the ratio of the total glazed/
window area to the entire wall area in that speciic
orientation), solar chimneys, attached sun spaces,
trombe walls, and so on, are extremely site-speciic
and must be located on orientations of the building that
complement the local site conditions. Passive heating
features should be located such that they absorb
maximum solar radiation though the day.
4. The height and distance of walls from a building can
Construction impact and inluence the ability of the building to exploit
of walls natural light and ventilation. Often it is observed that site
boundary walls are built up to 3 metres or 4.5 metres.
As mentioned earlier, impermeable obstructions such
as solid walls can create wind-shadow areas up to a
distance equivalent to 8–10 times the height of the wall.
This can seriously compromise the uniformity of wind
pressure and natural ventilation on the building site.
When the winds converge back on to the ground they
tend to create eddies that can further give rise to pockets
of high/low wind pressure. This further impacts the
comfort of the people on the site. So walls must be built
taking into account the likelihood of its impact on the site
and its surrounding areas.
