Page 129 - GRIHA Manual Volume III - Introduction to National Rating System

122 GRIHA Manual: Volume 3

Table-10 of SP41: Spacing distances between vertical or horizontal members of louver systems (Southern Region)
Spacing between vertical or horizontal angle of
Sr. Direction Type of inclination Direction of Performance Recommended
No. Louver B = inclination
B = 0° B = 15° B = 30° B = 45° 60°
Cuts off
sun after 7
A North V 2.75 p Inclining Not - am during For non-air-conditioned
case 1
June and
buildings
desirable
completely in
other months
Cuts off
Case 2 V 2.15 p - - - completely at For air-conditioned
buildings
all times
Cuts off all
B South H 2.75 p 3 P 3.33 P 3.75 P 4.5 P Downward summer sun Type H (B=0)
between 15
case 1
March and 30
September
Inclining
north way
summer and
C East/ West V Inclining up to 30 not desirable 0.53 P 1.27 P towards Cuts off both -
case 1
from the
winter sun
normal
Cuts off only
Case 2 H 0.27 P 0.54 P 0.85 P 1.27 P 2 P Downward after 7 am in Type C
summer and
winter
Completely
Inclining cuts off
Case 3 C vertical Inclining up to 150 0.31 P 0.73 P 1.46 P towards summer sun Combination of types
but allows
south away
member
V(B=30°) and H (B=0°)
not desirable
winter sun
from the
normal to come in
partially
Horizontal 0.84 P 1.11 P 1.42 P 1.84 P 2.57 P Downwards
member
North- Inclined Winter sun
negligible on
D East/ V 0.36 P 0.63 P 0.94 P 1.36 P 2.1 P towards this facade Type V (B=30°)
north away
North West
Case 1 from normal and summer
sun cut off
Case 2 H 0.36 P 0.63 P 0.94 P 1.36 P 2.1 P Downward -
South
away from
South
E -East / C vertical 0.58 P 0.85 P 1.15 P 1.58 P 2.31 P Southward Type C
member
-West normal
Case 1
Horizontal P 1.27 P 1.58 P 2 P 3.73 P Downward Combination of types
V(B=30°) and H (B=0°)
member
Source: SP41 document