energy efficiency for residential building

E N E R G Y E F F I C I E N C Y F O R

R E S I D E N T I A L B U I L D I N G S

I r . H . P. L o o i ( m e k t r i c o n @ g m a i l . c o m )

B . E n g ( H o n s ) , F I E M , J u r u t e r a G a s

h t t p : / /w ww. j k r. g ov. m y/ b s e ep /

2 CONTENT

1 E x e c u t i v e S u m m a r y

2 I n t r o d u c t i o n – T h e R e s i d e n t i a l B u i l d i n g S e c t o r

3 C o m p o n e n t s o f B u i l d i n g E n e r g y

4 E l e c t r i c a l Ap p l i a n c e s a n d M E P S

5 T h e r m a l C o m f o r t a n d P a s s i v e D e s i g n

6 E n e r g y U s e i n C o m m o n Ar e a s

7 R e v i e w o f I n t e r n a t i o n a l S t a n d a r d s

8 C o n c l u s i o n a n d R e c o m m e n d a t i o n s

9 Ap p e n d i x A – E s t i m a t i n g E n e r g y U s e f o r R e s i d e n t i a l

Ty p e s

1 0 Ap p e n d i x B – E s t i m a t i n g E n e r g y U s e f o r Ty p i c a l

Te r r a c e H o u s e ( C a s e S t u d y )

1 1 Ap p e n d i x C – M E P S & E n e r g y S t a r L a b e l

1 2 Ap p e n d i x D – B u i l d i n g T h e r m a l E n v e l o p e

1 3 Ap p e n d i x E – F a n g e r ’s T h e r m a l C o m f o r t

1 4 Ap p e n d i x F – S i m p l i f i e d f o r C a l c u l a t i n g R a d i a n t

Te m p e r a t u r e .4 t h M a r c h 2 0 1 5

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4 THE RESIDENTIAL BUILDING SECTOR

The building sector

consumes 15% of total

energy. The residential

building sector accounts

for 6% of total energy

consumption.

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We can conclude that, the use of primary energy at final consumer-end is more

efficient than the use of secondary-electrical energy. In this example, a clear

advantage of at least 2 times higher efficiency using gas-ring as compared to an

electric water heater. It should be noted that a ‘closed-type’ gas-heater has efficiency

as high as 90%. In such case, the site-source efficiency of enclosed-type gas heater

will be at least 3 times that of electric heater.4 t h M a r c h 2 0 1 5


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Arithmetic mean of electricity use based on sum total of all domestic consumers in Malaysia(kWh per domestic consumer per year).

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Average Monthly Sales in kWh 2009 2010 2011

Overall 481 489 470

HDB Public Housing 375 382 369

1-Room / 2-Room 149 154 153

3-Room 278 284 277

4-Room 387 394 380

5-Room and Executive 473 482 465

Private Housing 821 824 784

Private Apartments and Condo 678 679 644

Landed Properties 1203 1229 1190

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Landed properties constitute a major

proportion of housing types (more than

77%) with high-rise apartments and flats

constituting only 16% of housing stock

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14 NATIONAL HOUSEHOLD INCOME

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17 COMPONENTS OF BUILDING ENERGY

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24 ELECTRICAL APPLIANCES & MEPS

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25 MODELLING ENERGY USE & MEPS

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28 MODELLING ENERGY USE & MEPS - MACRO

Two cases of modelling are assumed;o Base case assumes no energy performance standards for the

appliances listed.o Case 1 considers 50% of households in urban area use

appliances with MEP standards;o Case 2 considers 20% of households in urban area uses

appliance with 5-Star energy performance standards.

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Recommendations:

NO MEPS exist for washing machine in Malaysia. Given that thepenetration rate of washing machine exceeds 90% in Malaysianhouseholds, it can be expected that an implementing MEPS forwashing machine may afford significant result in energy reduction forthe residential sector. The case study of Table 7 and Figure 11 indicatethat, even for 50% penetration in urban households, a 1% reduction intotal residential electrical energy (which amounts to about20GWh/month or about 14.8 ktonnes CO2 equivalent per month) canbe expected.

While MEPS for lighting has recently being made mandatory, no starlabel for lighting exist. It is recommended that the regulator draftenergy star labels for lighting.

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33 THERMAL COMFORT & PASSIVE DESIGN

Up to 50% of electrical energy is used for Cooling. Cooling energy is verymuch a component of Building Form. The following approaches to designingfor thermal comfort are adopted / available:

Building Thermal Envelope (OTTV & RTTV).

Calculating Cooling Load for Residential Space

Passive Design for Thermal Comfort (Cool House)

Thermal Mass

Natural Ventilations

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34 SUMMARY OF PASSIVE DESIGN

Design Approach Issues Addressed Technical Standards

Building Thermal

Envelope (OTTV and

RTTV)

(i) Reducing cooling load for

‘active’ air cond. (static load)

(1)ASHRAE fundamentals, chapter 17 and 18.

(2)MS1525

(ii)Thermal comfort (1)ASHRAE 55;

(2)ISO 7730

Cooling Load

Calculation

(i) Cooling load for ‘active’ air

conditioning units (static and

dynamic load)

(1)ASHRAE fundamentals, chapter 17 and 18

(2)MS1525

(3)ISO 13786

Building Thermal

Mass

(i) Reducing cooling load for

‘active’ air conditioning

(dynamic cooling load).

(1)ASHRAE fundamentals, chapter 17 and 18

(2)MS1525

(3)ISO 13786

(ii)Thermal comfort (1)ASHRAE 55;

(2)ISO 7730

Natural Ventilation (i) ‘Natural’ thermal comfort (1)ASHRAE 55;

(2)ISO 7730

(3)UBBL by-law 39 and 40

Day Lighting (i) Day lighting (1)MS 1525

(2)UBBL by-law 39

Table 8 – Summary of Passive Design and Technical Standards for Residential Buildings

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OTTV= 𝟏 −𝑾𝑾𝑹 𝒙𝑼𝑾𝒙𝑻𝑫𝒆𝒒 +𝑾𝑾𝑹𝒙𝑼𝒇𝒙𝜟𝑻 +𝑾𝑾𝑹𝒙𝑺𝑪𝒙𝑺𝑭

36 DECONSTRUCTING THE OTTV

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37 DECONSTRUCTING THE OTTV

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38 DECONSTRUCTING THE OTTV – WALL CONDUCTION

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Qw = Heat conduction through opaque wall = (1-WWR) x Uw x TDeq

TDeq = Temperature difference equivalent

Temperature difference equivalent method is a simplified model approximating the

final steady state condition of heat flow:

Outdoor and indoor ambient temperature ;

The thermal property of the wall which include:

1. Thermal resistivity (the converse is thermal conductivity)

2. Heat capacity and mass (the capacity of the wall to store heat)

The intensity of solar radiation striking on the surface of exposed wall

The radiant absorptivity of wall surface (alpha value);

The emissivity of the wall surface (sigma value)

Prevailing wind speed /air movement at the surfaces.


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40 DECONSTRUCTING THE OTTV – CONDUCTION


“An OTTV-based energy estimation model

for commercial buildings in Thailand”

Surapong Chirarattananon et al, 2004

Absorption refers to (radiant) heat

absorption capacity or the ALPHA

value.

Mass refers to thermal mass

(insulating and heat storage

capacity) of wall.


TD Malaysia Singapore Thailand Philippines

Wall TDeq 15 α ETTV: 12RETV: 3.4

12 (8 – 27.8) <50kg/m³: 15°K<230kg/m³: 12°K>230kg/m³ 10°K

Roof TDeq Light: 24Heavy: 20

12.5 12 (8 – 27.8) <50kg/m³: 24°K<230kg/m³: 20°K>230kg/m³ 16°K

Notes Light <50kg/m³Heavy<50kg/m³

ETTV: envelopethermal envelope:RETV: Residentialthermal envelope.

Tabulation ofTDeq whichdepends on wall/roof construction

Alpha value not considered. TDeq

depends on mass of wall.

Air cond inresidential is mainlyswitched on at nighttherefore lowerTDeq. Alpha is notconsidered.

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42 DECONSTRUCTING THE OTTV – WINDOWS CONDUCTION

A simplification assumes that

Tso ~ Toutside

Tsi ~ Tinside;

ΔT ~ Toutside - Tinside

Assume thermal mass and

absorptivity is negligible.

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43 DECONSTRUCTING THE OTTV – WINDOWS CONDUCTION

Malaysia Singapore Thailand Philippines

Wall glazing ΔT

6°K ETTV: 3.4°KRETV: 1.3°K

5°K Office: 3.35°KHotel: 1.1°K

Roof skylightΔT

6°K 4.8°K ?? ??

Notes

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44 DECONSTRUCTING THE OTTV – DIRECT SOLRAD GLAZING

The direct solar radiation

entering through glazing:

Solar radiation which is

dependent on time of day,

latitude, and seasonal

variation.

The solar shielding on the

glazing

The orientation of building

The inclination of building

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Malaysia Singapore Thailand Philippines

Average Sol Factor wall glazing (SFAV)

SF = FAV x OF

194 ETTV: 211RETV: 58.6

160 Office: 161Hotels: 142Stores: 151

OF (Orientation Factor)

0.9 – 1.23 ETTV:0.69 – 1.56 RETV:0.83 – 1.55

tabulation tabulation

Inclination of wall Not considered Yes in OF Yes in OF Yes in OF

Average Sol Factor skylight (SFAV)SF = FAV x OF

323 485 370 ??

l

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Sunlight is diffused

and reflected off the

landscape, reducing

heat gain the building

Direct Sun

Thai architect Dr Soontom Boonyatikam

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49 DECONSTRUCTING THE OTTV – WEATHER DATA

Source: ASEAN-USAID; Building Energy Conservation Project, Final Report; June 1992

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Source: Building Energy Efficiency Guidelines: Passive Design; (BSEEP, 2013, CK Tang)

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Source: ASEAN-USAID; Building Energy Efficiency Guidelines: Passive Design; (BSEEP, 2013, CK Tang)

Note: MS1525; Average Sol-Rad for wall glazing = 193

Average Sol-Rad for sky light = 323

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54 DECONSTRUCTING THE OTTV – CONCLUSION

The ‘building thermal envelope’ approachformulated principally as a tool for estimatingcooling load into buildings may be at adisadvantage in the case of residential buildings;where cooling loads are characterised by thefollowing

(b) Small heat gain. Heat gains in residential buildings are principally due to the thermalperformance of building envelopes and ventilation or air infiltration for the space airconditioned. Heat gain from electrical appliances and occupants are usually small(compared to commercial buildings).

(c) Diverse Space Usage. Space usage is highly diverse and flexible. This also means thatload usage profile is highly variable.

(d) Fewer Zones. Generally fewer zones are air conditioned (if at all). In typical Malaysianhomes only one or two rooms may be air conditioned. The thermal envelope conceptfor heat load in residential buildings may not be accurate.

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The OTTV and RTTV provide a measure ofthermal intensity (W/m²) on the buildingenvelope ‘exposed’ to the externalenvironment). The following should benoted:(a) The OTTV/RTTV method has as its

original aim the reduction of (active)cooling load. Notwithstanding, caveatslisted below it is a useful tool in thedesign of passive features of the buildingenvelope.

(b) An estimate of total cooling load due to external heat transfer into internal buildingspace can be estimated based on the thermal transfer values and area of exposedbuilding envelope. However where the percentage of air conditioned space is low, theaccuracy of cooling load will not be accurate.

(c) The OTTV method do not take into account other source of heat loads such as airinfiltration and latent and other heat sources from occupants and electric appliancesinside building

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Building Thermal Envelope (OTTV)

Roof Thermal Envelope (RTTV)

OTTV and RTTV provide an index of TOTAL external energy infiltration into internal

building space via the building envelope.


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Thermal comfort (ASHRAE 55[1] and ISO 7730[2]) is defined as the conditions

of environment which can be expressed as thermal comfort.

[1] ASHRAE 55 – Thermal environmental conditions for human occupancy[2] ISO 7730 – Moderate thermal environments – Determination of the PMV and

PPD indices and specification of the conditions for thermal comfort.

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Factors affecting thermal

comfort

Unit Secondary factors

(1)Metabolic rate of occupant W/m² Activity of occupant.

(1)Clothing Insulation m².°C/W Skin temperature of occupant.

(1)Air temperature (internal) °C outside temperature,

solar insolation,

thermal performance of building

envelope,

Air infiltration.

(1)Mean radiate temperature °C outside temperature,

solar insolation,

radiant emissivity of walls, ceiling,

glazing,

Thermal capacity of building mass at

vicinity.

(1)Air speed (internal) m/s Air infiltration, natural ventilation,

Presence of fan(s)

(1)Relative humidity % Air infiltration, natural ventilation.

Figure 13 – The thermal comfort model and six factors affecting thermal comfort

60 FANGER’S THERMAL COMFORT MODEL

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61 FANGER’S PMV TOOL

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64 FANGER’S THERMAL COMFORT ZONE

0.5 Clo

0.70 Clo

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65 FANGER’S RADIANT HEAT AND COMFORT ZONE

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66 SIMPLE RADIANT TEMPERATURE CALCULATOR

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14th November 2014

67 SIMPLE RADIANT TEMPERATURE CALCULATOR

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69 FANGER’S COMFORT ZONE USING ECOTECT

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70 FANGER’S COMFORT ZONE USING ECOTECT

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Image Courtesy: http://yourhome.gov.au/passive-design/thermal-mass

72 BUILDING THERMAL MASS

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The capacity of building material to store thermal energy andrelease it at a later period.

In the tropical context, building mass exposed to solar radiantheat will conduct and store thermal heat within its mass andrelease it during the cool evening night period.

A large thermal mass which iskept cool AND insulated orshielded or isolated from solarradiant heat acts as a thermalsink reducing the need for activecooling and improving thermalcomfort.


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Thermal properties of building material


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Traditional building material with thermal mass include water,rock, earth, brick, concrete, fibrous cement, ceramic tiles etc

Phase change materials store energy while maintaining constanttemperatures, using chemical bonds to store & release latentheat. PCM’s can store five to fourteen times more heat per unitvolume than traditional materials. (source: US Department ofEnergy).

PCM’s include solid-liquid Glauber’s salt, paraffin wax, and thenewer solid-solid linear crystalline alkyl hydrocarbons (K-18:77oF phase transformation temperature).


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Material Density(kg/m3)

Concrete 600-2200

Stone 1900-2500

Bricks 1500-1900

Earth 1000-1500 (uncompressed)

Earth 1700-2200 (compressed)

The basic properties that indicate the thermal behavior of materials are:

density (p), specific heat (cm), and conductivity (k).

The specific heat for most masonry materials is similar (about 0.2-

0.25Wh/kgC).

Therefore, the total heat storage capacity is a function of the total mass of

masonry materials, regardless of its type (concrete, brick, stone, and

earth).

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77 THERMAL MASS – THERMAL MASS CAPACITY

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An important property of thermal mass is the Thermal Time Constant of a building envelope.

TTC = heat capacity (Q) x resistance (R) to heat transmission.The TTC is representative of the effective thermal capacity of a building.

TTC/area=heat capacity/unit area (QA) x resistance to heat flow/area

QA=thickness x density x specific heat

Resistance = thickness/conductivity (or the U value).TTCA / area of a composite wall, the QAR value of each layer, including the outside and inside airlayers, is calculated in sequence. The QAR for each layer is calculated from the external wall to thecenter of the section in question:

QAiRi= (cm*l*p)i*(R0+R1+…+0.5Ri)For a composite surface of n layers, TTCA=QA1R1+QA2R2+…QAnRn .

The TTCs for each surface is the product of the TTCA multiplied by the area. Glazed areas are assumedto have a TTC of 0. The total TTC total of the building envelope equals the sum of all TTCs divided by thetotal envelope area, including the glazing areas.

A high TTC indicates a high thermal inertia of the building and results ina strong suppression of the interior temperature swing.

78 THERMAL MASS – DIURNAL HEAT CAPACITY

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DHC is a measure of the building’s capacity to absorb solar energy entering theinterior space, and to release the heat to the interior during the night hours. TheDHC is of particular importance for buildings in tropical zones.

The DHC of a material is a function of buildingmaterial’s density, specific heat, conductivity,and thickness. The total DHC of a building iscalculated by summing the DHC values of eachsurface exposed to the interior air.

The DHC for a material increases initially withthickness, then falls off at around 5”. Thisbehavior reflects the fact that after a certainthickness, some of the heat transferred to thesurface will be contained in the mass ratherthan returned to the room during a 24 hourperiod.

79 BUILDING THERMAL MASS – TTC AND DHC

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TTC and DHC

Relative values of TTC indicate the thermal capacity of the building

when a building is affected mostly by heat flow across the opaque parts

of the envelope (i.e., when it is unventilated, and when solar gain is

small relative to the total heat transfer through the building envelope).

Relative values of DHC, on the other hand, indicate the thermal

capacity for buildings where solar gain is considerable. The DHC also

is a measure of how much “coolth” the building can store during the

night in a night ventilated building.

Both measures indicate the amount of interior temperature swing that

can be expected based on outdoor temperatures (higher values

indicate less swing).

Delta T(swing)= 0.61Qs/DHCtotal,

Qs is the daily total solar energy absorbed in the zone.


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Software calculation tools under developmentHeat transfer matrix:

Zee=Zs2 Z Zs1

Where Zs1 and Zs2 are the heat

transfer matrices of the

boundary layers

Dynamic thermal admittance &

time shift of admittance


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Building which is externally insulated with internal exposed mass.

Here, both TTC and DHC are high. When the building is ventilated at night and closedduring the day, it can absorb the heat in the mass with relatively small indoor temperaturerise. Best for hot-dry regions.

Building with mass insulated internally.

Here, both the TTC is and DHC are low. The mass will store energy and release energymostly to the exterior, and the thermal response is similar to a low mass building.

Building with high mass insulated externally and internally.

Here, the building has a high TTC, but a negligible DHC, as the interior insulation separatesthe mass from the interior. When the building is closed and the solar gain is minimized, themass will dampen the temperature swing, but if the building is ventilated, the effect of themass will be negated. With solar gain, the inside temperature will rise quickly, as theinsulation prevents absorption of the energy by the mass.

Building with core insulation inside two layers of mass.

Here the TTC is a function of mostly the interior mass and the amount of insulation, and theDHC is a function on the interior mass. The external mass influences heat loss and gain byaffecting the delta T across the insulation.

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83 NATURAL VENTILATION

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Outdoor Air-Ventilation Rates should comply with Third

Schedule (By Law 41) Article 12 (1) of Uniform Building

By Laws, 1984 ( UBBL )

MS 1525:2007 - Section 8.1.4 Ventilation


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BUILDING TYPE MINIMUM FRESH AIR

VENTILATION cubic meter/min

RESIDENTIAL

COMMERCIAL

OFFICES

SCHOOL CLASSROOM

HOSPITAL WARDS

0.14/occupant

(0.23 lit/sec/m2 floor area

average)

CONFERENCE ROOMS 0.28/occupant

FACTORIES 0.21/occupant

Basement car Park (Mech) 6 air change/hour


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Thermal Comfort ;

ASHRAE DEFINITION 3 basic conditions in Passive Design for thermal

comfort:

Operative temperature

Air movement / Wind Speed

Relative Humidity

Fanger’s PMV-PPD

Thermal Comfort Model

(for conditioned space).

Adaptive Thermal Comfort

Model (for Natural and

Hybrid Ventilation Space).


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Natural means to maintain air

quality

Vents build-up of toxic gases and

indoor pollutants (principally

pathogens)

Low cost/ natural means of

maintaining indoor thermal

comfort.


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Wind-driven Cross Ventilation

Buoyancy-driven Stack Ventilation

Single-sided Ventilation


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Cross Ventilation


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STACK VENTILATION

93 NATURAL VENTILATION – WEATHER DATA K.L.

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OTTV/RTTV ; building envelope is not a good indicator of energy Passive

House. It is not even a good indication of air conditioning load in residential

building.

The Malaysia OTTV: uses worst case solar insolation and weather data. Other

metholody in OTTV development uses “averaged” solar and weather data to

Passive Low Energy Design can be approached from 2 perspectives:

1. Reduction of active cooling load by good thermal envelope (this approach

is not satisfactory

2. Thermal Comfort

Passive design for thermal comfort requires consideration of:

1. Thermal envelope with consideration of thermal mass (TTC & DHC);

2. Mean internal radiant temperature which is dependent on TTC & DHC;

3. Natural ventilation and the building form.g

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96 PASSIVE DESIGN – INNOVATION / RESEARCH

The following topics are briefly described (as a starting point

for detailed investigations/ further discussions):

1. The day (hot) / Night (cool) sky conundrum;

2. The riddle of the Cool Roof

3. Solar Chimney in the tropical context

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The Day – Night Sky Conundrum.

97 ROOF THERMAL POND


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Day – Solar radiant heat enter ing from the sky. Cei l ing

insulat ion wil l prevent heat from enter ing internal space.


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Dur ing the night the cool n ight sky acts as a heat s ink. The

cei l ing insulat ion however wi l l prevent heat f rom radiat ing out .

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The dynamics of cool ing/heat ing wi th in roof space

are governed by the fo l lowing heat t ransfer

problems:

Radiat ion

Convect ion

Radiat ion

102 THE COOL ROOF RIDDLE - CONDUCTION

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𝑄 = 𝐻𝑒𝑎𝑡 𝑓𝑙𝑜𝑤 (W/m²)

U =Conductivity (W/m.°K)

𝞩𝑇=Temperature gradient (°K/m)

103 THE COOL ROOF RIDDLE - CONDUCTION

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𝑄 = ℎ𝑥𝐴𝑥𝞩𝑇


h = Heat transfer coeff. (W/m².°K)

A = Area of heat transfer (ceiling in roof space)

𝞩𝑇=Temperature gradient (°K/m) between Troof2 and Tceiling1

104 THE COOL ROOF RIDDLE - RADIATION

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𝑄 = 𝞮 × 𝞼 × 𝐴𝐹 × (𝑇14 − 𝑇2

4)


𝞮 = Emissivity of surface (less than 1; with 1 for black body)

𝞼= Stephen Boltzmann constant

A = Area of view for radiation (roof and ceiling in roof space)

𝑇1= Troof2 and 𝑇2 = Tceiling1

105 WIND CATCHER

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"Malqaf" by Fred the Oysteri Licensed under GFDL via Wikimedia Commons -

http://commons.wikimedia.org/wiki/File:Malqaf.svg#mediaviewer/File:Malqaf.svg

106 WIND CATCHER

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"Egypte louvre 299" by Anonymous - Guillaume Blanchard, Juillet 2004, Licensed Wikimedia Commons -

http://commons.wikimedia.org/wiki/File:Egypte_louvre_299.jpg#mediaviewer/File:Egypte_louvre_299.jpg

Ancient Egyptian House miniature showing windcatchers, dating from Early

Dynastic Period of Egypt, found in Abou Rawsh near Cairo

107 SOLAR CHIMNEY

4 t h M a r c h 2 0 1 5

Solar collector to heat up

air (typically painted dark

colour

Chimney shaft to allow hot

air to rise

Openings to allow outside

draft to flow in.

108 SOLAR CHIMNEY WITH GROUND COOLING

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"Solarchimney" by Fred the Oysteri, Wikimedia Commons -

http://commons.wikimedia.org/wiki/File:Solarchimney.svg#mediaviewer/File:Solarchimney.sv

g

109 SOLAR CHIMNEY

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"Zion Visitors Center Cool Tower" by P. Torcellini, R. Judkoff, and S. Hayter, National Renewable Energy

Laboratory - http://www.nrel.gov/docs/fy02osti/32157.pdf. Wikimedia Commons -

http://commons.wikimedia.org/wiki/File:Zion_Visitors_Center_Cool_Tower.PNG#mediaviewer/File:Zion_Visit

ors_Center_Cool_Tower.PNG


4 t h M a r c h 2 0 1 5

Possib le area of research on E.E. in res ident ia l bu i ld ings

Retractable roof insu lat ion to al low radiat ion of heat into the

cool n ight sky.

Opt imis ing thermal mass ing for thermal comfor t (TTI , DHC).

Opt imis ing pass ive des ign for a natura l ly cooled house.

The use of ground as a heat s ink. Channel a i r pre cooled in

underground chamber before di rect ing into in ternal space.

Current research shows 1m depth ground temp is 26.9ºC for

the whole year round.

The cool roof r idd le .

111 UNFINISHED BUSINESS

Building Mass

Radiant Thermal Temperature Tool

Benchmarking OTTV & RTTV to Fanger’s Thermal Comfort Model

The current model considers a typical terrace house only.

Modelling for high rise will be recommended.

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112 ASHRAE 90.2

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ANSI/ASHRAE Standard 90.2-2007

Energy-Efficient Design of Low-Rise Residential

Buildings.

Section 1 – Purpose

Section 2 – Scope

Section 3 – Definitions, Abbreviations, Acronyms and

Symbols

Section 4 – Compliance

Section 5 – Building Envelope Requirements

Section 6 – Heating, Ventilation and Air Conditioning

(HVAC) Systems and Equipment

Section 7 – Services Water Heating

Section 8 – Annual Energy Cost Method

Section 9 – Climatic Data

Section 10 –Normative References

Normative Appendix A – Envelope Performance Path

Trade Off Method

Normative Appendix B – Informative References

Normative Appendix C – Addenda Description

Information

E N E R G Y E F F I C I E N C Y F O R

R E S I D E N T I A L B U I L D I N G S

I r . H . P. L o o i ( m e k t r i c o n @ g m a i l . c o m )

B . E n g ( H o n s ) , F I E M , J u r u t e r a G a s

h t t p : / /w ww. j k r. g ov. m y/ b s e ep /T h a n k Yo u f o r Yo u r A t t e n t i o n

energy efficiency for residential building

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