HOT & DRY

CLIMATESubmitted by :

RAHUL ASODARIYA 02DARSHAN BAVADIYA 04MANSI BORAD 06VATSAL GADHIYA 11NIKHILESH DHADUK 10RIDHAM VEKARIYA 39DARSHAN SAVSAIYA 34MITALI GONDALIYA 01

The general characteristics of this climate are as follows:

•hot dry weather in summer and cold in winter.

•very little rainfall.

•very low humidity.

•sandy or rocky ground with very low vegetation cover.

•high temp. difference between night and day.

•hot winds & frequent dust storms

•High summer day time temperatures(32-36° C)

•In hotter regions above 40 and up to 50°C.

• High solar radiation

•Clear sky most of the year

Hot & Dry regions: Ahmedabad, Rajasthan, North Africa, Kutch, Pakistan, etc.

INTRODUCTION TO ITS DESIGN

PRINCIPLES…

•The architecture that has developed in arid zones have had consistent and deep-rooted building techniques which promote passive climatic conditioning of their environments to provide shelter and comfort from their natural environment of hot-arid deserts.

•Contemporary design of homes in hot-arid desert conditions have much to learn from the great history and development of city planning, building form and construction methods of the past.

Case Study of a Traditional House

BUNGHA HOUSE“Architecture without Architects”

•A circular space enclosed by mud walls is the most typical dwelling

construction in the Kutch district of the Gujarat state & Rajasthan in India, which has a very high earthquake risk, is called a Bungha.

Materials used

1. Stone 2. wood 3. Bamboo4. burnt brick masonry either in mud mortar

or in cement mortar.5. Straw

Characteristics

•consists of a single cylindrically shaped room.•has a conical roof supported by cylindrical walls. •inner diameter of the Bungha is between 3m to 10m.•has only three openings one door and two small windows.

•construction has existed for several hundred years.•This house is quite durable and highly appropriate for hot & dry conditions.•The entire construction process, which is carried out by the mason with very few unskilled laborers, can be completed within 30 days.

•typically found in flat terrain.•do not share common walls with adjacent buildings. (the typical distance from a neighboring building is 3m)

Gives protection from

Rain

Solar radiation

Cracks

Earthquake

Wind circular design and the mesh of mud plaster and twigs make them resist any wind pressure and quake.

The different spaces (for men & women-children) are not interconnected.

A horizontal clay platform about 50 cm high, is a way to avoid rainfalls inside the house

Circular spaces are the main living zones, rectangular spaces are for secondary functions, like cooking cleaning and storing. They are smaller and not so strong. They do not resist very well to earthquakes or cracks.

The thick walls, made of mud, keep the interior cool when the temperature rises to 40 degrees Celsius in summer and warm when it beam and posts drops to 10 degrees in winter.

The roof is made of wooden top dome where bamboo sticks are fixed with a thick layer of grass put on roof and tied together.

The walls can not bear the wood beam of the roof, which runs across the space diagonally and rests on two wooden posts. The beam is often kept exposed outside the circular wall.

PLAN

•Due to circular shape of wall in plan, inertial forces developed in wall are resisted through shell action providing excellent resistance to lateral forces.

•wall is extended below ground up to the required foundation depth, and separate foundation is not traditionally constructed.

•The construction technique is such a way that improves seismic resistance of the inertia force generated in the roof

•a very unique aspect of traditional desert architecture in which the size, location and orientation of the Bungha are planned for very good structural and functional results.

The ``modern’’ version had given a go by to traditional architecture replacing the twigs ofthe `babul’ trees with stones.

Case Study of a Modern House

THE PAREKH HOUSE- Charles Correa

•Two pyramidal sections from housing types developed for Cablenagar, Ahmedabad.

•Summer section – to be used during daytime; protects interior from heat

•Winter section – to be used in early mornings and evenings; opens up the terraces to the sky

•Since site faces east-west, house consists of 3 bays

•Summer section sandwiched between winter section and service bay (for circulation, kitchen and toilets)

•Bearing walls made brick .

Features… •Level differences•Sun path : N-E to N-W•Exposure of east and west façade to the sun.Hence the design came…the three block system..•Over head pargolas-helps in shading the wall during the day time.•Recessed or Sunken windows-allows only diffused light into the building.•Louvered doors-it also cuts off the heat and direct sun coming from the entrance.•STEP PYRAMIDAL form of spaces inversing with respect to the season.•Garden space in front of the house.•Material chosen-concrete and brick covering.

Ground floor plan

First floor plan

Store

A Sustainable Structure !! Climate Responsive Structure !!

Elements of Vernacular ArchitectureFor different Hot-Dry Regions around the world

Main Objective:the common basic function is to protect the structure from weather conditions

1. Mediterrean House

•Walls made in raw earth bricks, cooked bricks, stone or tuff. 50 cm - 100 cm thick walls accordingly to the construction materials.•Roof characterized by light wood structure, more often in bricks and lime.•Closed volumes, few and little windows.•There isn’t roof projection, but often there are stairs outside to reach the flat terraced roof.

Region around the Mediterrean sea, like in Greece, South Italy, Spain & South France

Trulli House, South Italy

•the huge massive stone is usually joint to a big basin to collect rainwater used to decrease of 6-7°C the interior temperature in summer. •This allows the natural ventilation through the dome holes and is improved by the white color of the exterior surface made in lime

2. Arabic House

•the climate is so dry, the temperature range is so high, there’s a strong solar radiation and the winds can transport huge amount of dust and sand.

The architecture design was developed following tradition, culture, religion and climate answers. The features are:•building shape•wall typologies•interior spaces distribution openings•ventilation and cooling systems

The whole design is focused around the central square-shaped patio: an empty space where all the rooms face to.

Around the patio often there are porches on one or more sides and one or more stored.

1. NIGHT: the cool air comes down in the court and goes inside each room that face to it. The flat roof and the thick walls also improve the cooling system.

2. AFTERNOON: the sun directly heat the walls that face to the court. The air heats and goes up providing for the natural ventilation. The court works as a chimney. The massive walls and doors protect the interior spaces from the direct solar radiation.

3. EVENING: the air is so hot and the court door heats creating a natural air flow from the rooms that face to it through the patio. The last cool air goes out from the rooms in the evening, but also the shadows are longer and quickly the court is protected from the radiation.

To improve these passive systems they usually fix a wet curtain on the court and a fountain in the middle.

Al Bahar -Cool building in Abu Dhabi’s heat

•curtain wall systems but this usually provides poor external views, lack of optimal natural light and introduces excessive shine outward.

•Alternatively, shading fixed devices, the "mashrabiya" in Al Bahar Towers has a number of components transparent umbrella that open and close in response to the sun's path.

•Each of the two towers comprising more than 1,000 individual sunscreens are controlled via the building management system, creating a smart facade.

Mashrabiya’s opening sequence

Section

Plan

The Mashrabiya’s are given near the employee’s working area, giving a comfortable place to work in.

3. Underground Architecture

•The underground architecture use the soil constant temperature to have a better indoor comfort. The most famous underground settlement in the mediterrean area are: Cappadocia in Turkey, Mat-Mata in Tunisia and the typical Italian and Spanish underground settlements.

•This architecture was born not only to answer climate features, but also for social reasons and defence necessities

•Mat-mara in northern Tunisia consists in houses placed around a big court dig into the rock: this court is the central point ofthe spaces distribution.

•Different rooms face to the court: bedrooms, kitchen and storage.The particular shape protects from the hot climate, but also from the dusty and sandy desert winds

4. American Pueblos

•The building technology is adobe often mixed to straw and covered with a thick raw earth plaster. •The 75 cm thick walls can easily collect heat during the day to use it during the night, when the temperature decreases a lot. •The windows are few and well protected in order to avoid the heat entrance and the light to dazzle at noon

•consists in three lines of buildings and the distance between them is designed to allow the sun radiation for all the houses.

•In each building the stores are staggered to create terraces on the roof

OVERVIEW OF DESIGN PRINCIPLES..

Courtyard or Patio White Colored walls (“cool” colours reduce heat reflection ) Arrangement of the houses in is very closely packed to each other. Vegetation (reduces the temperature, filter’s the dust in and around the house, elevates the humidity level may reduce as well as increase the wind speed) small openings double roof or white single roof thick walls big basin to collect rainwater louvered windows pergolas a water body

•Therefore, the roof should slope down towards the courtyard, and be surrounded by a parapet at the upper edges, air in contact with the roof will be cooled at night and channelled by the slope into the courtyard and then into the rooms.