Natural ventilation : Case Study

NATURAL VENTILATION CASE STUDY: 1.MBF TOWER, MALAYSIA 2.MOULMEIN RISE, SINGAPORE

MBF TOWER MALAYSIA

MBF TOWER, PENANG MALAYSIA KEY INFORMATION

SITE MICRO CLIMATE ANALYSIS

Project: MBF Tower Year of completion: 1994 Location: Latitude of 5.2° N and Longitude of 100.2° E, Penang, Malaysia Climate: ‘Tropical warm & humid Architect: TR Hamzah and Yeang Client: MB FHOLDINGS BERHAD Site Area: 7482.39 Sq.mt Site and situation: City landscape surrounded by low rise and high rise structures Prevailing wind direction: from south-west and northeast Type: Mixed (office & Residential) Building height: 111.1 meters Number of storey: 31 (Till six stories building is occupied With conditioned office, space and rest are naturally ventilated residential flats) Structure: Reinforced Concrete

As per the Climate Classification chart, the site falls in the tropical climate, which is warm, sunny and humid, along with high rainfall especially during the southwest monsoon from April to September. The climate shows no distinct hot or cold seasons with a little seasonal and diurnal

RELATIVE HUMIDITY

TEMPERATURE

ARCHITECT’S DESIGN IDEAS • • • •

Tropical high-rise design ideas Cut outs in the building acting as Sky Courts Units are separated from the lift core for all-round cross-ventilation The typical open floor plans are designed to be column free and cross ventilated • Stepped planters on the facade of the building • Units are seaward facing on western edge.

PRECIPITATION

WIND Showing yearly pre dominant wind directions

Built Form and Orientation Muscular rectangular form with four blocks in one floor and exposed column holding the gigantic built structure is oriented approximately north south, facing towards sea on northeast. Optimum orientation of each space to prevailing breeze and strong linkage between leeward and windward sides strengthen the utilization of the pressure difference to facilitate cross ventilation,

GROUP – 11

Showing Sun-Path diagram cover MBF Tower

Sun path diagram Winter solstice

Sun path diagram Equinox

Sun path diagram Summer solstice

NIKHIL KUTLEHRIA (196030), ROHIT SAXENA (196035), SUMIT LATHWAL (196041)

MBF TOWER, PENANG MALAYSIA PLANS Ground Level Floor Plan

Podium Level Plan

Typical Residential Floor Plan The plan is oriented in such way; both sides i.e. north east and north side walls of the flat get maximum benefits from north easterly prevailing wind and vice versa for south westerly wind. The width and depth of each flat is at 1:2 ratios. The north east facing flats are having floor area of 74.4 sq.mt and southwest facing flats has area of 69sq.m with width and depth aspect ratio of 1:2 with maximum width of 5.2m.

Typical Podium Level Roof Plan

NATURAL VENTILATION STRATEGY The main objective of the wind induced natural ventilation principle was to generate high air-changes to achieve comfort conditions by controlling indoor temperature and airflow rate. Minimum use of internal partitions and maximum number of (single, double and three sided)‘openings in each room facilitate the wind induced cross ventilation. Window Openings are placed with respect to windward and leeward side of the building, which enhance the airflow rate in the habitable spaces. In this regard, the exposed ‘mega structure” is the first building of its own kind that exploits windinduced natural ventilation not only for the purpose of air-displacement and fresh air supply but also to create indoor thermal comfort for the residents.

Front and Side elevation of the MBF Tower GROUP – 11

NIKHIL KUTLEHRIA (196030), ROHIT SAXENA (196035), SUMIT LATHWAL (196041)

MBF TOWER, PENANG MALAYSIA QUANTITATIVE ANALYSIS

CONCLUSION

• Effect of orientation of the building block with respect to the prevailing wind direction.

Building is situated at 250m away from the sea and the northeast wind hits the building front face at an angle of THE TOP-LEVEL PLAN OF THE TOWER. 75°.

• Effect of sky court

• The building’s natural ventilation strategy is generally successful in relation to its form, orientation and the prevailing wind directions.

• Sky courts enhance the indoor airflow rate.

• Seashore areas get benefit from the daytime sea breeze, which maximize speed in the afternoon, and night-time land breeze, which provides thermal comfort of low temperature and higher wind speed.

• . Insertion of transitional spaces acts like isolated bungalows.

• Orientation of the tower enhances the effectiveness of wind induced cross ventilation as the tower is having openings towards the prevailing wind direction.

• Oblique wind enhances the indoor airflow rate • When the wind changes direction northeast to southwest, wind would still hit the southwestern building blocks at an oblique angle of 75°.

• Effect of Orientation

Further investigation and suggestions • Due to its form, orientation and location, the effectiveness of wind induced natural ventilation strategy applied can be highly reliable.

• Stepped terrace gardens could enhance the effectiveness of natural ventilation.

• The central core could be utilized as a wind-trapping zone, which can enhance the indoor airflow rate.

Showing the Central Core of the Tower GROUP – 11

Sky Court

Northeast pre dominant wind direction with respect to tower

Southwest pre dominant wind direction with respect to tower

• The higher air-changes per hour are facilitated with both vertical and horizontal floor gaps and slots.

• Only two flats have a good sea view and direct sea breezes out of the four flats in each floor.

• Green terrace gardens are maintained, which might help to cool the tower during afternoon time.

• Each apartment blocks have proper cross ventilation, but it has the option for air-conditioning.

Showing Vertical Landscape NIKHIL KUTLEHRIA (196030), ROHIT SAXENA (196035), SUMIT LATHWAL (196041)

MOULMEIN RISE SINGAPORE

MOULMEIN RISE, SINGAPORE

GROUP – 11

NIKHIL KUTLEHRIA (196030), ROHIT SAXENA (196035), SUMIT LATHWAL (196041)

▪ ▪ ▪ ▪ ▪

Total 50 apartments.

Two apartments per Floor.

Each having area 95 m2.

Lift & stair core at centre.

Living & dining spaces facing South.

▪ Bedrooms and kitchen facing North.

GROUP – 11

NIKHIL KUTLEHRIA (196030), ROHIT SAXENA (196035), SUMIT LATHWAL (196041)

➢ With two apartments per floor, the slender tower designed properly to allow cross ventilation as well as single sided ventilation. ➢ The building is oriented North-South for optimized environmental performance with minimum solar gain and maximum cooling potential. ➢ The north facade is cladded with sliding perforated panels to maximize the solar shading as well as natural ventilation. ➢ Deep overhangs on the facades (1 meter on the north and 0.6 meter with vertical sunscreens on the south) provide shading from the direct sun and help keep out driving rain. ➢ This building incorporates monsoon windows –horizontal openings that let in the breeze but not the rain.

GROUP – 11

NIKHIL KUTLEHRIA (196030), ROHIT SAXENA (196035), SUMIT LATHWAL (196041)

MOULMEIN RISE, SINGAPORE CONCLUSION • • • • •

The building’s wind induced natural ventilation strategy is generally successful in relation to its form, orientation, solar exposure and the prevailing wind directions.

For most of the period the natural ventilation strategy could not be applied to achieve indoor thermal comfort for Singapore climate. during most of the time, it is possible to have indoor thermal comfort with indoor air speed of 2 m/s for Singapore.

Variable openings help the occupants to control their indoor environment.

It enhance indoor airflow rate, due to large opening in the south living room ,however the high airflow rate due to high wind speeds at high altitudes might cause discomfort for the residents.

Façade of the Tower

Façade of the Tower with sun screen

• • • • •

GROUP – 11

Central core is also naturally cross ventilated which consumes less energy.

From vernacular design ideas, the horizontal “monsoon window” designed by taking inspiration to keeps the rain out, while allowing continuous cool breeze into the indoor space.

The materials choice used in the tower is equally the Smart especially the perforated sunscreen, which allows indoor airflow by keeping the rain out.

The cross ventilation strategy mainly done by wind force.

In a tall building, since wind speeds are much amplified on the sky garden, which enhance indoor airflow as well as air permeability is lack in the Moulmein Rise tower.

FURTHER INVESTIGATIONS AND SUGGESTIONS •

• •

Natural ventilation strategy applied in the tower can be highly reliable for the full year except certain time especially during the afternoon and evening time of the summer months.

To get indoor thermal comfort, dehumidification might help during high humidity period.

Hence, minimizing the solar radiation and maximizing the opening in the prevailing wind direction and especially in the west and east facade might improve the effectiveness of wind-induced ventilation in the tower.

NIKHIL KUTLEHRIA (196030), ROHIT SAXENA (196035), SUMIT LATHWAL (196041)