Page 70 - GRIHA Manual Volume II - Introduction to National Rating System
P. 70
62 GrIha Manual: Volume 2
In this case, as mentioned previously, the total site area refers to the site area used to calculate
floor area ratio/floor space index.
In this case, imperviousness paving % = (5411.15/12 500) x100 = 43.3%
The permissible imperviousness for a commercial area according to NBC 2005 is 70%–90%.
Therefore, the project meets both aspects of Appraisal 5.3.1. The appraisal requires that the
project complies with the more stringent aspect of the two. In this case, we realize that the more
stringent aspect of the appraisal is less than 25% paved area. Since the project complies with this
aspect, the project gets awarded 1 point for the same.
Appraisal 5.3.2 targets reducing the impacts of the paved surfaces on site. Surface parking
forms a huge consolidated hard paved area on site. Reducing the surface parking to the minimum
number, as required by the local building bye-laws, the consolidated hard paved area on site is
further reduced. This part of the appraisal is mandatory and should be complied with.
Once the total paved area on site is minimized, steps are to be taken to reduce their impact
further. This can be done by either adopting various soft paving strategies like pervious paving or
open grid pavers or grass pavers. The paved surfaces can be shaded by a vegetated roof or a pergola
with planters or a pergola with solar PVs, etc. Besides these, the hard paved surfaces can be topped
with high-albedo paint in order to ensure minimum absorption of direct solar radiation.
In the example, the total paved area is Net Paved area (from equation 1) + soft paved area = 2700
+ 216 = 2916m 2
As per the requirements, the following treatments were done to the various paved surfaces.
Table 3 Calculating paved surface with high SRI/shaded/softscape surfaces
Surface Area (m )
2
Grass area in landscape pathway 216
Paving with High SRI (emergency paving around the building and sidewalk) 1095
Paving with vegetated pergolas (surface parking and café court) 153
Total 1464
According to commitment 5.1.2, either 50% of the total paved area should be under pervious
paving or should have high SRI or should be shaded through the use of pergolas and planters. It
also states that 50% of all the paved surfaces can have a combination of above measures in order to
meet the appraisal 5.3.2.
Therefore from Equation 4
(Pervious paving + paving with vegetated roof/shading + paving with high SRI) > 50%
Total paved area
that is, (216+153+1095 )
= 50.25%
2916
Therefore, based on appraisal 5.3.2, the project achieves 1 point.
In this case, as mentioned previously, the total site area refers to the site area used to calculate
floor area ratio/floor space index.
In this case, imperviousness paving % = (5411.15/12 500) x100 = 43.3%
The permissible imperviousness for a commercial area according to NBC 2005 is 70%–90%.
Therefore, the project meets both aspects of Appraisal 5.3.1. The appraisal requires that the
project complies with the more stringent aspect of the two. In this case, we realize that the more
stringent aspect of the appraisal is less than 25% paved area. Since the project complies with this
aspect, the project gets awarded 1 point for the same.
Appraisal 5.3.2 targets reducing the impacts of the paved surfaces on site. Surface parking
forms a huge consolidated hard paved area on site. Reducing the surface parking to the minimum
number, as required by the local building bye-laws, the consolidated hard paved area on site is
further reduced. This part of the appraisal is mandatory and should be complied with.
Once the total paved area on site is minimized, steps are to be taken to reduce their impact
further. This can be done by either adopting various soft paving strategies like pervious paving or
open grid pavers or grass pavers. The paved surfaces can be shaded by a vegetated roof or a pergola
with planters or a pergola with solar PVs, etc. Besides these, the hard paved surfaces can be topped
with high-albedo paint in order to ensure minimum absorption of direct solar radiation.
In the example, the total paved area is Net Paved area (from equation 1) + soft paved area = 2700
+ 216 = 2916m 2
As per the requirements, the following treatments were done to the various paved surfaces.
Table 3 Calculating paved surface with high SRI/shaded/softscape surfaces
Surface Area (m )
2
Grass area in landscape pathway 216
Paving with High SRI (emergency paving around the building and sidewalk) 1095
Paving with vegetated pergolas (surface parking and café court) 153
Total 1464
According to commitment 5.1.2, either 50% of the total paved area should be under pervious
paving or should have high SRI or should be shaded through the use of pergolas and planters. It
also states that 50% of all the paved surfaces can have a combination of above measures in order to
meet the appraisal 5.3.2.
Therefore from Equation 4
(Pervious paving + paving with vegetated roof/shading + paving with high SRI) > 50%
Total paved area
that is, (216+153+1095 )
= 50.25%
2916
Therefore, based on appraisal 5.3.2, the project achieves 1 point.
