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S. F. Ali and D. Rakshit
4.1.3 Thermal Comfort: A Necessity
ASHRAE Standard 55 (ASHRAE 2010) defines thermal comfort as the condition of
the occupants in agreement with their thermal environment, estimated subjectively. It
represents a balanced state between the occupants and their environment determined
when heat by occupant’s metabolism process is dispersed into the environment.
Nowadays, designing an efficient building solely on the basis of energy requirements is not sufficient. The thermal comfort of the occupants, along with other
comfort criteria should be met for a building to be called efficient. The occupants
incline towards easier methods of retaining a thermally comfortable environment,
hence opt for auxiliary systems of space conditioning. This results in an increase in
the consumption of energy in buildings. Hence, passive methods should be adopted
in buildings to the greatest extent possible not only for lowering down the demand
for energy, but also for sustaining the recommended thermal comfort. Studies have
proven that passive techniques are useful in achieving comfort conditions. There
have been many such studies, such as that done by Haase and Amato (2009) wherein
they checked the influence of natural ventilation and orientation in improving the
thermal comfort of the occupants, by Ravikumar and Prakash (2009) wherein the size
of the openings were adjusted in order to achieve thermal comfort conditions, by Liu
et al. (2018) where an optimum window-to-wall ratio and optimum thicknesses of
the insulation for the building envelope for meeting the required comfort was found,
by Berkovic et al. (2012) where a particular configuration as well as orientation of
a building was proposed for thermal comfort, or study of different arrangements for
window-door by Daghigh et al. (2009), or provision of a partition wall for comfort
improvement, as shown by Aryal and Leephakpreeda (2016), etc. The various passive
techniques that can be employed in buildings for maintaining comfort conditions for
the occupants are (Haase and Amato 2009; Ravikumar and Prakash 2009; Liu et al.
2018; Daghigh et al. 2009; Aryal and Leephakpreeda 2016; Gadi 2010; Zahiri and
Altan 2016; Kamal 2012; Berkovic et al. 2012):
• Orientation
• Building Form
• Window-to-Wall Ratio
• Arrangement and Size of Openings
• Envelope Construction
• Envelope Materials
• Thermal Insulation
• Glazing
• Provision of Shading Devices
• Provision of Partition Walls
• Induced Ventilation Techniques (such as solar chimneys, wind towers, etc.)
• Earth Coupling Techniques (such as provision of earth air tunnels, etc.)
• Provision of Thermal Storage Components (such as Trombe walls, water walls,
etc.).
In case if the passive techniques employed are not able to meet the required
comfort, then efficient active techniques should be implemented in order to fill the
S. F. Ali and D. Rakshit
4.1.3 Thermal Comfort: A Necessity
ASHRAE Standard 55 (ASHRAE 2010) defines thermal comfort as the condition of
the occupants in agreement with their thermal environment, estimated subjectively. It
represents a balanced state between the occupants and their environment determined
when heat by occupant’s metabolism process is dispersed into the environment.
Nowadays, designing an efficient building solely on the basis of energy requirements is not sufficient. The thermal comfort of the occupants, along with other
comfort criteria should be met for a building to be called efficient. The occupants
incline towards easier methods of retaining a thermally comfortable environment,
hence opt for auxiliary systems of space conditioning. This results in an increase in
the consumption of energy in buildings. Hence, passive methods should be adopted
in buildings to the greatest extent possible not only for lowering down the demand
for energy, but also for sustaining the recommended thermal comfort. Studies have
proven that passive techniques are useful in achieving comfort conditions. There
have been many such studies, such as that done by Haase and Amato (2009) wherein
they checked the influence of natural ventilation and orientation in improving the
thermal comfort of the occupants, by Ravikumar and Prakash (2009) wherein the size
of the openings were adjusted in order to achieve thermal comfort conditions, by Liu
et al. (2018) where an optimum window-to-wall ratio and optimum thicknesses of
the insulation for the building envelope for meeting the required comfort was found,
by Berkovic et al. (2012) where a particular configuration as well as orientation of
a building was proposed for thermal comfort, or study of different arrangements for
window-door by Daghigh et al. (2009), or provision of a partition wall for comfort
improvement, as shown by Aryal and Leephakpreeda (2016), etc. The various passive
techniques that can be employed in buildings for maintaining comfort conditions for
the occupants are (Haase and Amato 2009; Ravikumar and Prakash 2009; Liu et al.
2018; Daghigh et al. 2009; Aryal and Leephakpreeda 2016; Gadi 2010; Zahiri and
Altan 2016; Kamal 2012; Berkovic et al. 2012):
• Orientation
• Building Form
• Window-to-Wall Ratio
• Arrangement and Size of Openings
• Envelope Construction
• Envelope Materials
• Thermal Insulation
• Glazing
• Provision of Shading Devices
• Provision of Partition Walls
• Induced Ventilation Techniques (such as solar chimneys, wind towers, etc.)
• Earth Coupling Techniques (such as provision of earth air tunnels, etc.)
• Provision of Thermal Storage Components (such as Trombe walls, water walls,
etc.).
In case if the passive techniques employed are not able to meet the required
comfort, then efficient active techniques should be implemented in order to fill the