CHAPTER 3 Window design for day lighting, ventilation and to

Transcription

1 for day lighting CHAPTER 3 Window design for day lighting 3.1 Guideline:

2 for day lighting 3.2 Mandatory clause For air-conditioned buildings!"!#$$%& # '()!!"!#$$%& * '()! #!"!#$$% Table 3.2.1: Vertical fenestration U-factor and SHGC requirements as recommended in ECBC 2007 Maximum U-factor Maximum SHGC Maximum SHGC for 40% Climate (Wm 2 -K) for WWR 40% < WWR 60% Moderate For naturally ventilated non-air-conditioned buildings +- Development of Building Regulations and to

3 for day lighting 3.3 Technical guidelines Windows in air-conditioned buildings.. + (0.! # + + (0.! 1 (0.!. Figure 3.3.1: Types of heat energy flow occurring through window Development of Building Regulations and to

4 for day lighting &3 & ) -. Figure 3.3.2: Types of double pane glass with low-e coating and gas fills Development of Building Regulations and to

5 for day lighting Figure 3.3.3: Heat flow through a double-pane glass 2 4 ' '()! &. '()! '()! ' 2 5 ' 1'()! Development of Building Regulations and to

6 for day lighting - '()! Figure 3.3.4: Projection factor for a window '()! - '()! Development of Building Regulations and to

7 for day lighting Table 3.3.1: SHGC M factor adjustments for overhangs and fins Overhang 'M' factor for the projection factor Vertical fin 'M' factor for the projection factor Overhang + vertical fin 'M' factor for projection factors Orient Location ation North N latitude 15 or EW greater S Less N than 15 north EW latitude S " ) 4 44: ; Figure 3.3.5: Wall and window dimensions used for the calculation of the WWR Development of Building Regulations and to

8 for day lighting ( : ;<-=( Figure 3.3.6: Photograph showing wall and window position in a building Development of Building Regulations and to

9 for day lighting - & **% Figure 3.3.7: Day-lit zone explained in the figure as per the description above Development of Building Regulations and to

10 for day lighting 9 <#-> 4 <?@@ ## 06 Figure 3.3.8: Diagrammatic representation of the light shelf integrated in the window for daylight enhancement ## 06 Development of Building Regulations and to

11 for day lighting VLT For Various H:S VLT and WWR H:S - 1:5 H:S - 1:4 H:S - 1:3 H:S - 1:2 H:S - 1:1 Figure 3.3.9: Height to the separation ratio (HS) between buildings 20% 30% 40% WWR 50% 60% Figure : Graph displaying required WWR and VLT for various HS ratio 4 A (=' 44:06 Development of Building Regulations and to

12 for day lighting Windows in non-air-conditioned buildings 2 B '()! + 4; Figure : HSA and VSA measurement ' ** - + '2 ** - - Development of Building Regulations and to

13 for day lighting Figure : Commonly found shading devices ('. 0'. Table Solar angles for various cardinal directions Solar angles to be cut on various cardinal directions Cardinal directions HSA ( ) VSA ( ) North East West - 58 South North-east (NE) North-west (NW) South-east (SE) South-west (SW) Development of Building Regulations and to

14 for day lighting..2 ('. - A C * ('.DC 0'.E$ 9 0'. Figure : Horizontal shading devices used for cutting VSA E$ FD 1 D$F %C$ *** 22 9 <' -GH$ 0'.I A0'. Development of Building Regulations and to

15 for day lighting DC #H$% EC% EC% **D 22 Figure : Vertical shading devices used for cutting HSA 9 <' -G H$ ('.I A('. +2 Figure : Comparison between amounts of daylight penetration for deep overhang and louvers Development of Building Regulations and to

16 for day lighting + & (=' &44: Figure : Height-to-separation ratio (HS) between buildings Table Height-to-separation ratio and the required minimum WWR for adequate daylight in commercial buildings (non-air-conditioned) HS ratio (HS between buildings) Minimum WWR (%) required for adequate daylighting 1:5 20 1:4 20 1:3 20 1:2 20 1:1 20 & (=' &44: Development of Building Regulations and to

17 for day lighting Table Height-to-separation ratio and the required minimum WWR for adequate daylight in residential buildings (non-air-conditioned) HS ratios (HS between buildings) Minimum WWR (%) required for adequate daylighting 1:5 10 1:4 10 1:3 10 1:2 20 1:1 20 2:1 50 3:1 60 -(='44:! 44: F - ; H (=' <( =' <F=H <#= ' (='# 44: & C$J 4&.. + Development of Building Regulations and to

18 for day lighting! K L"! #$$C'KD(2A:& "- Table 3.3.5: Desirable wind speed (ms) for thermal comfort conditions: Clause National Building Code 2005 Dry bulb temperature Relative humidity (%) ( C) * * * * * * * 29 * * * * * * * * * ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** Table 3.3.6: Air change schedule SP41: Handbook on Functional Requirement of Buildings Space to be ventilated in residences Bedrooms Living rooms Offices K Required air change per hour Fig : Image to illustrate window and opening area and option to operate Development of Building Regulations and to

19 for day lighting ! - 2 L. Development of Building Regulations and to

20 for day lighting Fig : Image to illustrate wind speed with increasing height of the building ) L" 2 - '2 Development of Building Regulations and to

21 for day lighting Fig : Diagrammatic representation of stack effect in a room L B DC A#$ *$J *$J - -D$J +2 FCJ Table 3.3.5: Critical height requirement for physiological cooling Activity-based occupancy For sitting on chair For sitting on bed For sitting on floor Recommended height of the bottom side of the opening 0.75 m 0.60 m 0.40 m 2 2 Development of Building Regulations and to

22 for day lighting 3.4 s! " +!"!.& + #J!"! KDJ K2 # Payback Period Incremental Investment Cumulative savings Amount in lakh rupees Years Fig.3.4.1: Graphical representation of the payback period showing incremental investment and cumulative savings Development of Building Regulations and to