Page 151 - GRIHA Manual Volume IV - Introduction to National Rating System
P. 151
142 Griha Manual: Volume 4
• identify any glaring areas of energy wastage or inefficiency
• identify immediate improvements/ energy saving measures
Walk-through audits use existing, or easily available data and typically only major problem
areas can be identified during this type of audit. Immediate corrective measures are briefly
described, and quick estimates of implementation cost, potential operating cost savings,
and simple payback periods are provided. This level of detail, while not sufficient for
reaching a final decision on implementing proposed measures, is adequate to prioritize
energy-efficiency projects. Walk through audits help in determining the need for a more
detailed audit.
Detailed Energy Audit
The detailed energy audit expands on the preliminary audit by collecting more detailed
information about building operation and by performing a more detailed evaluation of
energy conservation measures. Additional metering through appropriate instruments
is often installed to supplement utility data. In-depth interviews with facility operating
personnel are conducted to get a better understanding of major energy consuming systems
and to gain insight into short- and long-term energy consumption patterns. Detailed energy
audit evaluates all major energy using systems in a building and provides a comprehensive
energy conservation implementation plan for the building. This type of audit provides
accurate estimate of energy and cost savings. An in-depth financial analysis is performed
for each measure based on detailed implementation cost estimates, site-specific operation
cost savings, and the building owner’s investment criteria.
2. Comfort audit
In addition to evaluating the overall energy performance of the building and all the major
energy using systems, energy audit also comprises of assessing the thermal and the visual
comfort of the building spaces. Thermal comfort performance of the building is defined
in terms of temperature and relative humidity maintained inside the building and visual
comfort is defined in terms of average illumination level in all the building areas measured
at horizontal work plane. Thermal and visual comfort audits are conducted to verify that the
building’s HVAC and lighting system are functioning appropriately and providing required
comfort to the building occupants.
Table 1 Inside design (Thermal comfort) conditions for air conditioned-areas as recommended by the National Building
Code-2005
Category Inside design conditions
Summer Winter
DB 21–23° C
DB 23–26° C
Restaurants RH 55%–60% RH not less than 40%
DB 21–23° C
Ofice buildings DB 23%–26° C RH not less than 40%
RH 50%–60%
DB 23–24° C
Hotel guest rooms DB 23%–26° C RH not less than 40%
RH 50%–60%
Source National Building Code - 2005
• identify any glaring areas of energy wastage or inefficiency
• identify immediate improvements/ energy saving measures
Walk-through audits use existing, or easily available data and typically only major problem
areas can be identified during this type of audit. Immediate corrective measures are briefly
described, and quick estimates of implementation cost, potential operating cost savings,
and simple payback periods are provided. This level of detail, while not sufficient for
reaching a final decision on implementing proposed measures, is adequate to prioritize
energy-efficiency projects. Walk through audits help in determining the need for a more
detailed audit.
Detailed Energy Audit
The detailed energy audit expands on the preliminary audit by collecting more detailed
information about building operation and by performing a more detailed evaluation of
energy conservation measures. Additional metering through appropriate instruments
is often installed to supplement utility data. In-depth interviews with facility operating
personnel are conducted to get a better understanding of major energy consuming systems
and to gain insight into short- and long-term energy consumption patterns. Detailed energy
audit evaluates all major energy using systems in a building and provides a comprehensive
energy conservation implementation plan for the building. This type of audit provides
accurate estimate of energy and cost savings. An in-depth financial analysis is performed
for each measure based on detailed implementation cost estimates, site-specific operation
cost savings, and the building owner’s investment criteria.
2. Comfort audit
In addition to evaluating the overall energy performance of the building and all the major
energy using systems, energy audit also comprises of assessing the thermal and the visual
comfort of the building spaces. Thermal comfort performance of the building is defined
in terms of temperature and relative humidity maintained inside the building and visual
comfort is defined in terms of average illumination level in all the building areas measured
at horizontal work plane. Thermal and visual comfort audits are conducted to verify that the
building’s HVAC and lighting system are functioning appropriately and providing required
comfort to the building occupants.
Table 1 Inside design (Thermal comfort) conditions for air conditioned-areas as recommended by the National Building
Code-2005
Category Inside design conditions
Summer Winter
DB 21–23° C
DB 23–26° C
Restaurants RH 55%–60% RH not less than 40%
DB 21–23° C
Ofice buildings DB 23%–26° C RH not less than 40%
RH 50%–60%
DB 23–24° C
Hotel guest rooms DB 23%–26° C RH not less than 40%
RH 50%–60%
Source National Building Code - 2005
