SEMINAR ON PASSIVE & ACTIVE DESIGN FOR ENERGY EFFICIENT BUILDINGS3 October 2014Holiday Inn Resort, Penang
h t t p : / / w w w. j k r. g o v. m y / b s e e p /
Part 1 – Introduction & Overview ofPassive DesignBy Ar Michael Ching Chee Hoong
2 ENERGY USAGE IN BUILDING
Buildings are responsible for 1/3 of energy related GHG emissions.
“Wasteful use of energy is affecting our planet and our environment. If we design, build and manage our buildings so the need for energy is reduced, only then our effort will make a real difference.”
3 SYNOPSIS
Passive design are features which are intrinsic (or part of ) the building form which contributes to good environmental qualities such as provides shelter or insulation against the hot tropical sun or its layout is such that it ensures quality environment for occupant.
Active design features are M&E systems which actively ‘intervene’ to ensure good or adequate environmental qualities in a building. Active measures include lifts, air conditioning, mechanical ventilation , artificial lighting etc.
4 SYNOPSIS
PASSIVE DESIGN measures are key considerations in the design of building for low energy and environmental performances. The importance of Passive Design is underscored by its precedence over Active Design measures in green and low energy building.
PASSIVE DESIGN measures (which are principally architectural in nature) aims to embed features into a building which are intrinsically green and low energy in nature. Active measures are design features which requires ‘active intervention’ of building systems (such as air conditioning, mechanical ventilation, lighting systems etc) which will contribute to green and/or low energy performances. Current pressing requirements for green design and low energy in building which are increasingly driven by mandatory building codes (e.g. recent revision to the UBBL incorporating parts of MS1525) requires knowledge of Passive Design as in the skill set of the design architect.
5 SYNOPSIS
Feature Passive Design Active Design
Ensure thermal comfort Building thermal envelope;
Natural ventilation
Air Conditioning System
Adequate and comfortable lighting
Natural daylight Artificial lighting
Ensure good air quality Natural ventilation Mechanical ventilation
Active design contributes to building energy.Passive design aims to reduce building energy and maximise comfort of the users.
We therefore need an understanding of Passive Design.
6 INTRODUCTION
THIS PRESENTATION introduces the topic of passive design in the following progressive manner:
(1)Building Energy
(2)Low Energy Building
(3)Passive Design
(4)Building Energy Components
8 COMMERCIAL BUILDING ENERGY
Typical Energy Use (kWh)
Typical Office Building
9 COMMERCIAL BUILDING ENERGY
Kings Green Hotel, Melaka (3 Star Hotel)
10 RESIDENTIAL BUILDING ENERGY
What About Residential Buildings?How do we measure Residential Building Energy?
In CETDEM study of around 2005, at least 55% of energy use is attributed to fuel for transport.
11 RESIDENTIAL BUILDING ENERGY
This is total Energy Use per family (middle income)
If we are only concerned with building energy, then we should only focus on electricity use.
12 RESIDENTIAL BUILDING ENERGY
But in many Malaysian home, if designed properly, no AC units are required.
13COMMERCIAL BUILDING ENERGY -- CONCLUSION
1. Air conditioning = 45% - 60%
2. Lighting = 15% - 25%
3. Utilities = 10% - 30%
4. General power outlets = 10% - 30%
These are dependent on building design.
This do not depend on building design.
It is possible to design a building which lessen energy use of those components listed above. These building components can be said to be “intrinsic” to the building OR part of the building ‘character’.
In Commercial buildings, we can conclude that building energy comprise the following:
14RESIDENTIAL BUILDING ENERGY -- CONCLUSION
In Residential buildings, we can conclude that building energy comprise the following (only for typical middle class Malaysian family:
For residential building a large part of building energy can be attributed to ‘life-style’ which may be due to socio-economic, cultural and even geographic location in nature.If is even possible for a residential building to be designed without air conditioning.
These are dependent on building design.
This do not depend on building design.
1. Air conditioning = 0% - 40%
2. Lighting = 8% - 20%
3. Appliances (fridge, oven) etc = 10% - 30%
4. General power outlets = 10% - 30%
KeTTHA Low Energy Building (LEO)
16 BUILDING ENERGY BENCHMARKS
Energy Consumption
Malaysia has the HIGHEST per capita Energy Consumption among ASEAN countries
17 BUILDING ENERGY BENCHMARKS
Why do we need Building Energy Benchmarks?Building Energy Benchmarks are indicators of building performance which is use as comparison between different building design (uniform gauge for comparison).
Building performance benchmarks are important:
1. Indication of building ‘environmental quality’ which may be demanded by the market forces.
2. Benchmarks on which regulatory requirement on building energy performance may be mandated, example: BEI (Building Energy Intensity) defined by GBI for compliance scoring
in the GBI environmental rating system. OTTV (Overall thermal transfer value) of building which is a form of
building energy performance benchmark which is now mandatory in some states
18 BUILDING ENERGY BENCHMARKS
For Commercial Buildings the following benchmarks by GBI & JKR-BSEEP:
Level
Office BEI per year
Hotel BEI per year
Resort BEI per year
Retail Malls BEI per year
Industrial BEI per
year
Data Centre (PUE)
1 150kWh/m² 200kWh/m² 245kWh/m² 240kWh/m² 180kWh/m² 1.9
2 140kWh/m² 190kWh/m² 230kWh/m² 225kWh/m² 150kWh/m² 1.8
3 130kWh/m² 175kWh/m² 212kWh/m² 210kWh/m² 140kWh/m² 1.7
4 120kWh/m² 160kWh/m² 196kWh/m² 195kWh/m² 130kWh/m² 1.6
5 110kWh/m² 150kWh/m² 181kWh/m² 180kWh/m² 120kWh/m² 1.5
6 100kWh/m² 135kWh/m² 165kWh/m² 160kWh/m² 110kWh/m² 1.4
7 90kWh/m² 120kWh/m² 148kWh/m² 145kWh/m² 100kWh/m² 1.3
8 - - - - 90kWh/m²
Low Energy Building (LEO) is any building performance, level 6 and below!
19 BUILDING ENERGY BENCHMARKS
Energy Consumption - BEI
Building Energy Index (kWh/m2/year)
Cu
mu
lati
ve p
erc
en
tile 80%
60%
40%
20%
0%50 100 200150 250 300 350 400 450
100%
Source : PTM
20 BUILDING ENERGY BENCHMARKS
For Residential Buildings NO BEI benchmarks, BUT building energy performance based on OTTV is practiced by GBI & JKR-BSEEP:
Levels GBI RNC Version 3 OTTV landed GBI RNC Version 3 OTTV High rise
1 50W/m² 50W/m²
2 46W/m² 46W/m²
3 42W/m² 42W/m²
4 38W/m² 38W/m²
5 34W/m²
6 30W/m²
21 BUILDING ENERGY BENCHMARKS
For Residential Buildings NO BEI benchmarks, BUT building energy performance based on OTTV is practiced by GBI & JKR-BSEEP:
Levels GBI RNC Version 3 OTTV landed GBI RNC Version 3 OTTV High rise
1 50W/m² 50W/m²
2 46W/m² 46W/m²
3 42W/m² 42W/m²
4 38W/m² 38W/m²
5 34W/m²
6 30W/m²
>75% of the Solar Gain by a typical Intermediate single storey terraced house is through its Roof
>40% of the Solar Gain by a typical 5 storey block of flats is through its Roof
23 BUILDING ENERGY COMPONENTS
Passive design features are features which are ‘intrinsic’ to the building (i.e. is an integral part or character of the building). Examples are orientation away from direct sun, well insulated building, windows to allow natural day-light Naturally ventilated building etc.
24 BUILDING ENERGY COMPONENTS
Passive design features are features which are ‘intrinsic’ to the building (i.e. is an integral part or character of the building). Examples are orientation away from direct sun, well insulated building, windows to allow natural day-light Naturally ventilated building etc.
Active design features are features which are building systems (usually mechanical and electrical in nature) which actively contributes to or enhances the performance of a building (‘performance’ may include energy or environmental quality). Examples are:Air conditioning systemMechanical ventilationArtificial lightingLifts & Escalators Plug Load & etc
25 BUILDING ENERGY COMPONENTS
Services Factors affecting kWh usage Parameters in design
ACMV Heat Transmission through walls/roof Weather Data
Solar irradiance OTTV, RTTV, Sun position & shading calculation
Air Infiltration Weather data
Human population/traffic Time-based traffic
Lighting load Human traffic, day light factor
Machine load Occupancy Pattern
Utility
Lighting Human traffic Occupancy Pattern
Day Lighting Sun Position, glare control
Power/ Plug Load
Human Traffic Occupancy Pattern
Utility Usage Pattern
26 MS1525 AND PASSIVE DESIGN
Code of Practice on Energy Efficiency and Use of Renewable Energy for Non-Residential Buildings
Now 3rd edition 2014
incorporated into UBBL in certain states, hence becomes part of a By-law
27 MS1525 AND PASSIVE DESIGN
MS1525 has the following Parts
0. Introduction
1. Scope
2. Normative Reference
3. Terms and Definitions
4. Architectural and passive design strategy
5. Building Envelope
6. Lighting
7. Electric power and distribution
8. Energy management and control system
28 MS1525 AND PASSIVE DESIGN
MS1525 Section 4 – Architectural and passive design strategy
1. Site planning & orientation
2. Daylighting
3. Façade design
4. Natural ventilation
5. Thermal insulation
6. Strategic landscaping and
7. Renewable energy (principally solar)
29 MS1525 AND PASSIVE DESIGN
MS1525 Section 5 – Building Envelope contains the following:
1. Concept of Overall Building Thermal Transfer (OTTV)
2. Sun path and building orientation
3. Shadings to mitigate solar insolation
4. Daylighting
5. Roofs thermal performance
6. Roofs with skylights
7. Air leakage
30 PASSIVE DESIGN FEATURES
Passive design features are can be listed as the following design measures:
1. To Orientation - Building Orientation (sun path)
2. To Shade - Building thermal envelope (OTTV) & Roof thermal envelope (RTTV)
3. To Insulate - Building thermal envelope (OTTV) & Roof thermal envelope (RTTV)
4. To Daylit - Natural day lighting by windows, daylighting system such as light tube, light shelf etc.
5. To Ventilate - Naturally ventilated building by cross and stack ventilation
31 PASSIVE DESIGN FEATURES
Passive design features are can be listed as the following design measures:
1. To Orientation - Building Orientation (sun path)
2. To Shade - Building thermal envelope (OTTV) & Roof thermal envelope (RTTV)
3. To Insulate - Building thermal envelope (OTTV) & Roof thermal envelope (RTTV)
4. To Daylit - Natural day lighting by windows, daylighting system such as light tube, light shelf etc.
5. To Ventilate - Naturally ventilated building by cross and stack ventilation
Building Envelope
20 March 2014
Qin
Tin (22°C)
20 March 2014
33CASE STUDY TO QUANTIFY THE BLDG ENERGY
Building design features which contributes to building cooling energy can be illustrated as follows:
Heat gain thro’ walls
Solar heat g
ain
thro
’ win
dows
Heat gain thro’ windows
Air Infiltration (doors/ windows/ cracks)
Fresh Air Intake People
heat gain Electric Appliance heat gain
Heat gain & solar heat gain thro’ roof (RTTV)
Lighting heat gain
Electric Motor
heat gain
20 March 2014
34CASE STUDY TO QUANTIFY THE BLDG ENERGY
Case study attempts to find out how much is the contribution of various building components
The Model:
20 March 2014
35CASE STUDY TO QUANTIFY THE BLDG ENERGY
Building Cooling Energy
20 March 2014
36CASE STUDY TO QUANTIFY BLDG ENERGY
Some Conclusion
Building façade contributes to about 15% of cooling energy
Roof contribution is proportional to the ratio of roof space to total built-up
Air intake or how ‘leaky’ a building is contributes up to a whopping 25% to building cooling energy.
Electrical equipment inside building contributes a major 30%. This component unfortunately is usually not influence by building designers but by the M&E engineer. However building designed with minimal or less dependency on electrical equipment will be have significant effect on building energy.
People or occupant only contribute from 15%-20% of bldg energy.
Understanding above and building usage pattern can assist designers in building low energy building.
SEMINAR ON PASSIVE & ACTIVE DESIGN FOR ENERGY EFFICIENT BUILDINGS3 October 2014Holiday Inn Resort, Penang
h t t p : / / w w w. j k r. g o v. m y / b s e e p /
Part 2 – Building Thermal EnvelopeBy Ar Michael Ching Chee Hoong
38 INTRODUCTION
THIS PRESENTATION introduces the topic of Building Thermal Envelope in the following progressive manner:
(1)Basic concepts in Building Thermal Envelope, MS1525
(2)OTTV and Roof U-Value
(3)Site Planning and Orientation
(4)Shading
(5) Insulation
(6)Daylight
(7)Natural Ventilation
Heat gain thro’ walls
Solar heat g
ain
thro
’ win
dows
Heat gain thro’ windows
Air Infiltration (doors/ windows/ cracks)
Fresh Air Intake People
heat gain Electric Appliance heat gain
Heat gain & solar heat gain thro’ roof (RTTV)
Lighting heat gain
Electric Motor
heat gain
40BASIC CONCEPTS - BUILDING THERMAL ENVELOPE
Building thermal envelope is based on the idea of Energy Input / Output to a system (in this case solar energy into building):
Qin
Tin (22°C) Tout (30°C)
41BASIC CONCEPTS - BUILDING THERMAL ENVELOPE
Building thermal envelope contributes up to 15% of building cooling energy which make up about 50% of total building energy.
43 THE CONCEPT OF OTTV
MS1525:2007 CLAUSE 5.2OTTV applies to building envelope
MS1525:2007 CLAUSE 5.5Roof U-value refers to the thermal transmittance of the roof construction
MS1525:2007 CLAUSE 5.6RTTV applies to roof with skylights
44 THE CONCEPT OF OTTV
A design criterion for building envelope known as the Overall Thermal Transfer Value (OTTV) has been adopted. The OTTV aims at achieving the design of building envelope to reduce heat gain through the building envelope and hence reduce the cooling load of the air-conditioning system.
The OTTV…should not exceed 50 W / m2
MS1525:2007 Clause 5.2
45 THE CONCEPT OF OTTV
Assumptions
The concept of OTTV is based on the assumption that the envelope of the building is completely enclosed.
In the OTTV formulation, the following items are not considered:
1.internal shading devices eg curtains
2.solar reflection or shading from adjacent buildings 3.green walls
`
46 THE OTTV FORMULA
SC) x WWR x CF x(194 U(WWR)6UWWR)(1α15OTTVi fw
MS1525:2007 Clause 5.2.2 says
+
HeatConductionthroughWindows
+
Solar HeatGainthroughWindows
HeatConductionthroughWalls
OTTV =
The formula for the OTTV of any given wall orientation is as follows:
0.2% to 5% 10% to 20% 70% to 85%
47 THE OTTV FORMULA
SC) x WWR x CF x(194 U(WWR)6UWWR)(1α15OTTVi fw
MS1525:2007 Clause 5.2.2 says
HeatConductionthroughWalls
OTTV =
The formula for the OTTV of any given wall orientation is as follows:
0.2% to 5%
48 THE OTTV FORMULA
SC) x WWR x CF x(194 U(WWR)6UWWR)(1α15OTTVi fw
MS1525:2007 Clause 5.2.2 says
+
HeatConductionthroughWindows
HeatConductionthroughWalls
The formula for the OTTV of any given wall orientation is as follows:
0.2% to 5% 10% to 20%
OTTV =
49 THE OTTV FORMULA
SC) x WWR x CF x(194 U(WWR)6UWWR)(1α15OTTVi fw
MS1525:2007 Clause 5.2.2 says
+
HeatConductionthroughWindows
+
Solar HeatGainthroughWindows
HeatConductionthroughWalls
The formula for the OTTV of any given wall orientation is as follows:
0.2% to 5% 10% to 20% 70% to 85%
OTTV =
50 THE OTTV FORMULA
SC) x WWR x CF x(194 U(WWR)6UWWR)(1α15OTTVi fw
α (alpha) = solar adsorbsion value of wall surface
WWR = window to wall ratio
Uw = U value ofwall
Uf = U value of fenestration (windows) W/m² K
CF = Correction Factor (due to orientation)
SC= Shielding Coefficient of windows.
51 THE OTTV FORMULA
SC) x WWR x CF x(194 U(WWR)6UWWR)(1α15OTTVi fw
1) Window to Wall ratio
2) Wall & Window Properties (including color)
3) Shading Devices
52 BUILDING ENERGY BENCHMARKS
53 THE CONCEPT OF ROOF U-VALUE
– Mass Insulation
– mass, thickness and thermal resistance slow down heat transfer
– Reflective Insulation
– reflect radiant heat
– low thermal emissivity
Common roof insulation materials
54 THE ROOF U-VALUE FORMULA
U-values are worked out from the Thermal Resistance of the respective materials making up the Roof, similar to that for Walls.
U-value is the heat transmission value of the composite roof in W/m2K, and is inversely proportional to R,
ie, U = 1 / Rtotal
The higher the R, the lower the U, the better.`
55 THE ROOF U-VALUE FORMULA
0.6Heavy
(Above 50 kg/m²)
0.4Light
(Under 50 kg/m²)
Maximum U-Value (W/m²K)Roof Weight
Group
MS1525:2007 Clause 5.5.1 Table 9. Maximum U-value for roof (W/m²K)
56ROOF CONSTRUCTION AND THERMAL VALUES
Metal Deck Roof with Insulation Component (outside to inside) Thickness Conducitvity Resistance mm w/(m.K) T/COutside Solar absorption 0.700Outside Surface Resistance 0.055Metal Deck (Aluminum) 0.5 221 0.000Fiberglass 100 0.035 2.857Air space 100 0.195Asbestos Free Ceiling Board 12 0.108 0.111Inside Surface Resistance 0.148Total Thermal resistance 4.266U-value (W/m2K) 0.234
57ROOF CONSTRUCTION AND THERMAL VALUES
Reinforced Concrete RooF Slab Component (outside to inside) Thickness Conducitvity Resistance mm w/(m.K) T/COutside Solar absorption 0.700Outside Surface Resistance 0.055Cement sand screed 25 0.533 0.047Polystyrene Foam 20 0.035 0.571Bitumen Felt Layer 5 0.5 0.010Reinforced Concrete slab 100 1.442 0.069Cement sand plaster 12 0.533 0.023Inside Surface Resistance 0.148Total Thermal resistance 0.923U-value (W/m2K) 1.083
1. Cement sand screed.
2. Bitumen /felt
3. Reinforced concrete
4. Cement sand plaster
58 INSULATION TO LIGHTWEIGHT ROOF
0 50 100 150 200 250 300 3500.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
RO
OF
U-V
AL
UE
(W
/m2K
)
INSULATION THICKNESS (mm)
MS 1525lightweight roof< 0.4 W/m2K
59 INSULATION TO HEAVYWEIGHT ROOF
0 50 100 150 200 250 300 3500.0
0.5
1.0
1.5
2.0
2.5
3.0
INSULATION THICKNESS (mm)
RO
OF
U-V
AL
UE
(W
/m2K
)
MS 1525heavyweight roof< 0.6 W/m2K
G Reimann
61 SITE PLANNING AND ORIENTATION
MS1525 Clause 4.3
Generally, the best orientation for buildings is with the long directional axis facing North-South, thus minimizing East-West orientation.
62 SITE PLANNING AND ORIENTATION
MS1525:2007 Clause 4.3
The micro-climate, shading, radiant temperature, wind direction, precipitation etc should be analysed for the locality.
64 SHADING DEVICES - HORIZONTAL
The reasons for shading is to shield windows from the direct solar radiation which is a major cause of solar heat gain (up to 70-85%) Shading can be horizontal / vertical.
Vertical shading device.
65 SHADING DEVICES - HORIZONTAL
66 SHADING DEVICES - HORIZONTAL
MS1525:2007 Table 5
If R1 falls between increments, adopt the next larger ratio. If R1 is below 0.30, SC2 = 1.If R1 is > 2.00, SC2 values shall be the same as R1 between 1.30 and 2.00
67 SHADING DEVICES - HORIZONTAL
68 SHADING DEVICES - VERTICAL
Vertical shading device.
69 SHADING DEVICES - VERTICAL
70 SHADING DEVICES - VERTICAL
MS1525:2007 Table 6
If R2 falls between increments, adopt the next larger ratio. If R2 is below 0.30, SC2 = 1.If R2 > 2.00, SC2 values shall be the same as R2 is between 1.30 and 2.00.
71 SHADING DEVICES - VERTICAL
72 SHADING DEVICES - EGGCRATE
Eggcrate Shading DevicesMS1525:2007 Table 7
73 SHADING DEVICES - EGGCRATE
WHAT IS WRONG WITH THIS DIAGRAM?
75THERMAL VALUES OF BUILDING MATERIALS
Heat flows when outside temperature is higher then inside temp. The thermal property of material at building envelope are measured by its thermal
transmissivity value. The inverse of transmissivity is resistivity. The thermal property of building material will be an factor in building energy.
76THERMAL VALUES OF BUILDING MATERIALS
Normal Brick WallNormal Brick Wall External Component (outside to inside) Thickness Conducitvity Resistance mm w/(m.K) T/COutside Surface Resistance 0.044External Plaster 20 0.55 0.036Bricks 115 0.807 0.235Internal Plaster 20 0.55 0.036Inside Surface Resistance 0.120Total Thermal resistance 0.472U-value (W/m2K) 2.637
Conductivity of common brick walls:
(a) 115mm clay bricks, U=2.6 W/m² °K
(b) 230mm clay bricks, U=1.9 W/m² °K
(c) 115mm aerated bricks, U=2 W/m² °K
(d) 230mm aerated bricks, U=1.3 W/m² °K
Conductivity of cavity brick walls:
(a) 2x115mm clay bricks with , U=1.4 W/m² °K
Wall with cavity
Normal brick wall
77 ALPHA VALUE OF SURFACE
Alpha value of surface measures the impact of surface due to its absorption of solar radiation. A ‘stronger’ color will have a higher alpha value. Alpha value will directly cause the temperature of a surface to rise.
78 ALPHA VALUE OF SURFACE
SRI = 27
Roof Surface Temperature = 70.7°C
SRI = 86
Roof Surface Temperature = 49°C
79 GLAZING THERMAL VALUES
1. Visible light transmittance % of visible light passing through
2. Visible reflectance; % of visible light reflected
3. SHGC (Solar Heat Gain Coeff) or SC (Shading Coeff); ratio of solar incident heat to solar heat transmitted.
Glazing Properties
80 GLAZING THERMAL VALUES
Glazing Properties1. Visible light transmittance % of visible light passing
through
2. Visible reflectance; % of visible light reflected
3. SHGC (Solar Heat Gain Coeff) or SC (Shading Coeff); ratio of solar incident heat to solar heat transmitted.
4. U Value; heat transfer property due to outdoor/indoor temp. difference – W/M² - °K
5. R-Value is resistance to heat transfer = 1/U.
6. UV Light Transmittance; % of UV lights passing through.
7. Spectral Selectivity: Ability to react selectively to different wavelengths of light.
8. Glazing Colour: visible light filter affecting colour/tint of glaze.
9. Sound Transmission: ability to transmit sound.
Types of GlassThere are three generic low solar heat gain glass types in used in Green Building in the market today:
1. High Performance Float Glass; low U and SC Value
2. Tinted Glass
3. Low-E Glass
81 GLAZING THERMAL VALUES
Types of Low-E GlassThere are three generic low-e types in use in the market today:
1. High Solar Gain Low-E
2. Low Solar Gain (Solar IR Absorbing) Pyrolytic Low-E
3. Low Solar Gain (Solar IR Reflecting) Sputtered Silver Low-E
The 1st type of high solar gain low-e is not suitable for tropical climate use because it is meant to allow solar radiation to be transmitted into the building and then trapping it within the building to heat it up. This type of low-e glazing is suitable for cold climates where heating is the predominant energy used in a building.
The 2nd and 3rd type of low-e (Solar IR absorbing and reflecting) is perfect for a tropical climate such as Malaysia’s because it stops the solar radiation on the glazing itself by absorbing it or reflecting and reradiating it back outside.
82 GLAZING THERMAL VALUES
Single Glazing Low-EThese are hard coated metallic coatings on the surfaces of glazing that can be exposed to the indoor climate. The metallic coating on the inside surface reduces the emissivity of the glazing by 70% to 80%, thereby reducing the heat that is radiated into the internal spaces, while allowing heat to be radiated back outdoors. This glazing will provide better comfort conditions for the building occupants due to its lower radiant heat and will indirectly allow the airconditioning temperature to be raised to maintain comfortable conditions. It is also important to note that adding low-e to single glazing only lowers the SHGC effectively if it is on a tinted glass or the coating has a heat absorbing layer. It is not difficult to find single glazing low-e products with a LSG between 1.0 and 1.3.
Double Glazing Low-EThese are soft coated metallic coatings on the surfaces of glazing that cannot be exposed. These coatings have to be protected in between the glazing. These metallic coatings on the inside surface reduces the emissivity of the glazing by 95% or more, thereby reducing the heat that is radiated to the internal spaces.
83 GLAZING THERMAL VALUES
Case calculationReducing the amount of windows(glazing) on building façade).
84 GLAZING THERMAL VALUES
Case calculationReducing the Solar Heat Gain Capacity (U value) of glazing. .
85 GLAZING THERMAL VALUES
87 DAYLIGHTING
MS1525:2007 Clause 4.4
Conventional and innovative daylighting systems that collect, transport, and distribute light deep into buildings that reduce the need for artificial lighting are recommended.
88 DAYLIGHTING – DAYLIGHT FACTOR
Conventional and innovative daylighting systems that collect, transport and distribute light deep into buildings and systems that reduce the need for artificial lighting are recommended.
The simplest form of description of daylight distribution is Daylight Factor, DF where
DF = (Internal Illuminance/External Illuminance) x 100%
Refer MS1525:2007 Table 1
MS1525:2007 Clause 4.4
89 DAYLIGHTING – DAYLIGHT FACTOR
Zone DF (%) Distribution
Very bright > 6 Thermal and glare problems
Bright 3 - 6 Good (Not good, glare)
Average 1 - 3 Fair (Good)
Dark 0 - 1 Poor (Fair)
Based on Malaysian data, the average Daylight level between 10am and 4pm is 30,000 lux.
Thus, a suggested DF of 1.5 = 450 lux (Fair); a DF of 4.5 = 1,350 lux (Very very
bright!)
MS1525:2007 Table 1
90 DAYLIGHTING – LIGHT SHELVES
LIGHT SHELVESwith horizontal shading devices
91 DAYLIGHTING – LIGHT SHELVES
2m 4m 6m
ceiling
Light shelf
92 DAYLIGHTING – LIGHT SHELVES
A. No lightshelf and no louvres
External lightshelf and no louvres
B.
OUTSIDE INSIDE OUTSIDE INSIDE
93 DAYLIGHTING – LIGHT SHELVES
With lightshelf and louvres
C. Lightshelf tilted at 30o and without louvres
D.
OUTSIDE INSIDE OUTSIDE INSIDE
94 DAYLIGHTING – LIGHT SHELVES
Lightshelf tiled at 30o and with louvres
E. With outer and internal lightshelves
F.
OUTSIDE INSIDE OUTSIDE INSIDE
95 DAYLIGHTING – LIGHT SHELVES
0
1
2
3
4
5
6
A B C D E F
Glare risk
Preferred
Based on DF of 1.0%, ie approx 300 lux
5.7m
4.8
3.7
4.9
5.0
3.9
96 DAYLIGHTING – LIGHT PIPES
98 NATURAL VENTILATION
MS1525:2007 Clause 4.6
Natural ventilation is the use of the natural forces of wind and buoyancy……to ventilate internal spaces and provide thermal comfort with reduced energy.
99 NATURAL VENTILATION
100 CONCLUSION – FAÇADE DESIGN
MS1525:2007 Clause 4.5
The building envelope should be designed to provide an integrated solution for the provision of minimizing heat gain, daylight control, moisture management systems, view and passive & active solar energy collection.
SEMINAR ON PASSIVE & ACTIVE DESIGN FOR ENERGY EFFICIENT BUILDINGS3 October 2014Holiday Inn Resort, Penang
h t t p : / / w w w. j k r. g o v. m y / b s e e p /
Thank you