ANALYSIS OF MENARA PJH (LOT 2C2), PUTRAJAYA.

01

// East Facade of Menara PJH

MENARA PJH

The building's longest facade is facing East and West which contradicts to the basic building design principles. (MS 1525: 2014) This orientation results in higher building heat gain throughout the day. The building was built in this orientation maybe because of site boundary restrictions and they needed to maximize built-up area. Due to this orientation, East ad West facade need shading device.

03

TEMPERATURE & HUMIDITY

AVG INDOOR (OFFICE) Table A

AVG OUTDOOR Table B

N

02

SOLAR ANALYSIS Vertical fins

SUN CHART

SITE PLAN

//Red colour line is the boundary of Lot 2c2, which was purchased by Putrajaya Holdings. (Jafri Merican Architect, 2011)

Figure 1.2 N

//The building orientation also maximizes the view on the Putrajaya Bridge / Jambatan Seri Wawasan (A) and the Putra Mosque (B)

Data collected (Table A and B) is obtained during our site visit on 24th October 2017. The annual humidity in Putrajaya is averagely 80% and the maximum and minimum annual temperature of Putrajaya is 31.7 °C and 22.5 °C respectively. (World Weather and Climate Information, 2016) The outdoor temperature and humidity measured on site is similar to the annual average temperature and humidity of Putrajaya. The recommended indoor humidity is between 75% to 70%. (MS 1525: 2014) and the average indoor humidity is 71% (Table A). This shows why the windows of Menara PJH are mostly sealed according to observation on site to reach the humidity standard. With the presence of vertical fin, the temperature and humidity in the building interior is effectively decreased. (Refer to Figure 4.4)

Shadow

The building receives maximum sunlight on East & West facade. Therefore, vertical fins are installed at the East and West facade as sun shading device to increase natural ventilation and thermal comfort to reduce heat gain in the interiors without air conditioning as well as reducing the energy consumption in the area with airconditioning. Block B, C and D are shaded by Block A during noon and afternoon of the day. Therefore, no vertical fins are needed at these blocks.

Figure 1.1 N

PUTRAJAYA

GBI GOLD Location: Lot 2C2, Persiaran Barat, Presint 2, 62000 Putrajaya, Wilayah Persekutuan Putrajaya Latitude: 2.9299 °N Longitude: 101.6882 °E The construction of the office green building on Menara PJH (Lot 2C2), marks the first of its kind in the main commercial boulevard of Putrajaya and underscores the city’s status as a pioneer of green technology such as solar renewable energy, grey water recycling system. shading device, rain water harvesting and site layout to reduce vehicles carbon emissions.

ORIENTATION

Figure 2.1 // Annual sun path in 2016 at 4pm on 21 Mar, 21 Jun and 21 Dec at Menara PJH simulated with http:// sunearthtools.com/

Figure 2.2 // Interior of Menara PJH's West facade at 4pm shaded by the vertical fins.

EAST FAÇADE receives highest exposure to sunlight in the morning. (Refer to 4.1 ) WEST FAÇADE receives highest exposure to sunlight in the afternoon. ( Refer to 4.3 )

04

HEAT GAIN ANALYSIS N

kWH/m2 50 40 30

10 AM

1 PM

4 PM

Figure 4.1

Figure 4.2

Figure 4.3

20 10 0

East facade receives maximum heat gain in the morning.(Figure 4.1). West facade starts to gain heat at noon. (Figure 4.2). West facade receives maximum heat gain in the afternoon.(Figure 4.3). Thus, shading devices are needed to shade the East and West facade. However, wind velocity (Figure 6.2 & 6.3) helps to carry away the heated air (Figure 5.4). Therefore, there's sufficient air flow in the building despite being exposed to sunlight in the afternoon. (Refer to Figure 6.1) Figure 4.1, 4.2 & 4.3 show the heat gain analysis throughout the day. Figures generated by software Insight Revit 2016

05

06

PASSIVE DESIGN

VERTICAL FINS

Zone with air-conditioning

The vertical fins are made up of 2 components. Outside - Tinted Glass Inside - Ceramic Fritted Glass

Figure 5.1

WIND ANALYSIS

Figure 5.2

// Close-up of vertical fins

B Figure 5.3

Figure 5.2 shows the black dots filling up the fins to block visible light and reduce heat transmission into the building.

A

//black dots pattern

C D

// Vertical fins of West facade

Zone without air-conditioning

The figure 6.1 shows that wind direction with high fre quency comes from West (figure 6.2) and Southwest (figure 6.3) at speed between 0 km/h to 7km/h maximum. Based on site observation, all the windows of Menara PJH are operable. The tallest block (Zone A) uses natural ventilation without air-conditioning as it directly receives wind from West. Zone A blocks the wind coming from West and Southwest (Figure 6.2 and 6.3). Therefore, zone B, C and D need air-conditioning to regulate air flow in the interior. N

Interior (Table A)

Exterior (Table B)

Gap 29.40 °C

28.80 °C

30.23 °C 27% absorbed by vertical fins

4.4% absorbed by Low E-Glass

30%

% 43

7% 13.

9.9%

% 100

2%

Convection The remaining 30% of heat enters the space between the vertical fins and low E-glass. 9.9% of heat is carried away by the wind with a velocity of 8km/h, while 20.1% of heat remains. (Figure 5.5 & 5.6) (Thermal Analysis and Design of Passive Solar Buildings, 2002) Conduction The building facade is made up of single glazed low E-glass, according to Mr. Mohd Azren. 2% of the remaining 20.1% heat is reflected by the low E-glass. (Kien Safety Glass, 2009), 13.7% of heat enters the building.

Figure 5.4 Heat transfer diagram not to scale Heated air Wind flow

Velocity (km/h)

Radiation According to Mr.Mohd Azren, assistant of Green Building department, the vertical fins are made up of tinted glass (Shine Solar Film, 2015) and fritted glass (OldCastle Building Envelope, Architectural Glass, 2011) (Figure 5.3) which reflect 43% of heat and absorb 27% of heat.

30.23°C and 28.80°C are the average outdoor and indoor temperature respectively, measured on 24th October 2017 (Refer to Table A & B). The data is collected at 4th floor, installed with operable windows and shaded by vertical fins. The 29.40°C is based on our estimation using the average outdoor and indoor temperature.

Figure 6.1 // Figure 6.1 shows the wind rose of Putrajaya and the figure 6.2 & 6.3 shows the wind velocity at Menara PJH simulated with https://www.enviroware.com/cgibin/windrose.cgi and revit flow design version 2016 respectively.

07

Figure 6.2

Figure 6.3

THERMAL COMFORT

Humidity Ratio (%)

PSYCHROMETRIC CHART Average Indoor Dry-Bulb Temperature & Humidity (Refer to Table A) Figure 5.5 Perspective view of West facade (Refer to Figure 6.1) not to scale

Thermal Comfort (MS1525:2014)

To achieve thermal comfort, the dry-bulb temperature should range from 23˚C to 26˚C whereas humidity should range from 75% - 70%. (MS1525:2014,) The vertical fins have successfully reduced the indoor temperature (refer to Table A & B). Therefore, the average indoor dry-bulb temperature and humidity is closer to the thermal comfort zone. In order to achieve the thermal comfort zone, air-conditioning and fans can be used. Figure 7.1 is generated by http://www.energy-design-tools.aud.ucla.edu/

Interior

Dry-Bulb Temperature (°C )

CONCLUSION Figure 5.6 Plan view of West facade (Refer to Figure 6.1) not to scale

Figure 7.1

Based on the building orientation. East and West facade receive maximum sunlight exposure in the morning and afternoon. According to our research, we can evidently prove that the vertical fins act as an effective shading device for the interiors which reduces heat gain to achieve thermal comfort. Consequently, the vertical fins aid to increase energy efficiency in air conditioned area, whereas, in non air conditioned area, operable windows reduces heat gain are present to allow natural ventilation to cool down the interior. The vertical fins act as shading to the building environment. In a nutshell, the vertical fins play a huge part for the building to meet the requirements to archive GBI GOLD.

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