THE USE OF THE DOUBLE ROOF STRUCTURE TO REDUCE HEAT GAIN IN THE CLIMATIC RESPONSIVE DESIGN

OF THE SAFARI ROOF HOUSE, PETALING JAYA

ASIAN ARCHITECTURELEE JO YEE0314880

INTRODUCTION The role of a roof

ROLES OF ROOFROOF IS PART OF A BUILDING ENVELOPE.

It is the covering on the uppermost part of the building or shelter which provide protection from animals and weather, notably rain or snow, but also heat, wind and sunlight. The elements in a design of a roof are:

1. The materials

2. The construction

3. The durability

The shape of roofs differs greatly from region to region. Climates and materials are the main influences the shape, structure and outer covering.

https://en.wikipedia.org/wiki/Roof

ROOF IN TROPICAL CLIMATETROPICAL RAINFOREST CLIMATE:

1. Average temperature maintains around 30 – 32 degree Celsius. Rarely goes beyond 34 degree Celsius or lower than 20 degree Celcius.

2. High rate in precipitation. Heavy rain falls uniformly in each month of the year.

3. Relativity humidity is excessive, around 77% to 88%.

4. Enable a broad range of flora and fauna.

5. It can be concluded as Hot and Humid Climate.

6. Strong wind and experience Monsoon Seasons which is the Southwest Monsoon from late May to September, and the Northeast Monsoon from November to March.

MALAY VERNACULAR ARCHITECTUREOf Malay traditional houses in Malaysia, the design of the roof differs from states to states to indicate the local culture. However, the function and principles behind the design are more or less the same. They have exhibited similar characteristics to tackle the local warm and humid climate.

http://www.hbp.usm.my/conservation/Measured%20Drawings/mapmalay.jpg

PITCHED ROOF

DOUBLE VOLUME -ALLOW VENTILATION FROM ROOF SPACE ABOVE-CATCHES WIND AT HIGH VELOCITY

DOUBLE ROOF CONCEPT-EXTRA OPENINGS AT THE ROOF GAP

DOUBLE ROOF STRUCTURE The role of a roof

TYPES OF ROOFTraditional roofing can be divided into Pitched-Roof and Flat Roof. There are three main types of pitched roofs namely

Single Roofs

Double Roofs

Trussed Roofs

Trussed rafter roof – modern construction

“A double roof is a roof whose rafters are of such a length that they require an intermediate support. This support is usually a beam which is secured under the rafters at a point half way between the ridge and the wallplate. This beam is known as a purlin.”http://www.unitcare.com.au/pdfs/roof_structures_explained.pdf

“A timber framing system in which thecommon rafters rest on purlins whichprovide intermediate support.”

http://encyclopedia2.thefreedictionary.com/double+roof

The purpose of a common purlin roof may be allow a board roof, allowing a wider building. https://en.wikipedia.org/wiki/Purlin

TYPES OF ROOFFlat roof are found in traditional buildings in regions with a low precipitation. Modern materials which are highly impermeable to water make possible the very large low-pitch roofs found on large commercial buildings.

DOUBLE SKIN ROOF SYSTEM

The double skin roofing system is a high performance system comprising of a metal sheet on the top and a metal trapezoidal tray at the bottom. http://www.rockwoolasia.com/products/residential+and+commercial+buildings/single+-c12-+double+skin+roof+solutions

Single Skin Roof System

Second Roof

LIFTED / ELEVATED

HOUSE OF DOUBLE-ROOF by Shigeru Ban- Yamanashi, Japan, 1993One more layer of roof is added and lifted from the building original roof to allow air to pass through.http://www.shigerubanarchitects.com/works/1993_house-of-double-roof/index.html

No matter it is a pitched roof or flat roof, they are of same intention which is introducing passive cooling strategies in Tropical Climate :

1. Reducing heat gain into the building interiors

2. Allow ventilation to achieve thermal comfort

TYPES OF ROOF

roofs

pitched

Single roof Double roof Trussed roof Trussed Rafters roof

flat

Double skin Elevated

The definition of Double Roofs is varied but shall not be confused. There are many designs and combinations of double roofs. The design of the roof will depend upon the size and shape of the ground floor plan of the building.

CASE STUDIESROOF – ROOF HOUSE BY KENNETH YEANG

LOCATION: AMPANG, MALAYSOA

ARCHITECT: KEN YEANG

YEAR COMPLETED: 1984

CONCEPT: Shade the enclosure of the building as an “environmental filter” that making good use of the climatic advantage and overcoming the climatic disadvantage.

CASE STUDIESFEATURES: Huge concrete louvered roof which covered the building is known as “umbrella architecture”. The outer curved roof acts as a solar filter to the rest of the house, and regulates the daylighting values of the house.

In hot sunny afternoons, lots of the overheated sunlight is being reflected by the louvers out of the building.On the other hand, during the mornings and the late afternoons, the louvered roof permits light penetration into the house can light up the space.

http://www.chinagb.net/case/resident/residence/20070307/20808.shtml

CASE STUDIESDOUBLE ROOF PAVILLION also known as GAZEBO

Is a structure that often built in a park, garden or spacious public area. They provide shade, shelter, ornamental features in a landscape, and a place to rest.

PROVIDE ROOF LIGHTING AND HIGH LEVEL VENTILATION

Body level ventilation

Roof level ventilation

Heat radiation

Heat radiation

Hot air being carried away along with high velocity wind.

Wind is invited into the space below

THE ADAPTATION IN SAFARI ROOF HOUSE

The role of a roof

TROPICAL LANDROVER =

TROPICAL LANDROVER = SAFARI ROOF

FLAT ROOF + DOUBLE ROOF

FLAT ROOF + DOUBLE ROOF

FLAT ROOF + DOUBLE ROOFCARRIED AWAY HEAT GAIN

FLAT ROOF + DOUBLE ROOFEXCESS WIND

VENTILATION GAP

TO THE ROOF TOP

FLAT ROOF + DOUBLE ROOFHEAT HAS BEEN FILTERED IN THE FIRST LAYER BEFORE ENTERING THE BUILDING.

CORRUGATED BITUMINOUS SHEETAS PURE SUNBREAK

THERMAL CAPACITY

MATERIALS

SURFACE REFLECTIVITY

REFERENCES APA style

Bibliography 1. Burhanuddin, W. (1984). The Malay House: Learning from its elements, rules and changes. In L. a.

(eds.), Design Policy: Design and Society (pp. 28-33). http://www.hbp.usm.my/wburhan/malayhouse/mhousepaper.htm This paper provides an introduction to the Malay Vernacular architecture and details on each physical elements, spatial elements and functional elements.

2. Low, K. M. (2015, September 29). Safari Roof House. Retrieved from archnet.org:

http://archnet.org/sites/6469/publications/2223 http://archnet.org/system/publications/contents/2223/original/FLS2600.pdf?1384757902 This is a presentation panels of the Safari Roof House explained everything from concept implimentation to execution. In the publication also shows series of photos taken from different angle in the house to provide a better understand of the spatial arrangement.

3. Paul Gut, D. A. (1993). 3.3 Design for warm-humid zones. In D. A. Paul Gut, Climate Responsive

Building - Appropriate Building Construction in Tropical and Subtropical Regions. Switzerland: SKAT. http://collections.infocollections.org/ukedu/en/d/Jsk02ce/3.4.html This book writes about the suggested approaches and strategies in tackling climate issues in various context. A focus is placed in chapter 3.3 where it talks about the design implication in hot and humid climate.