19.10.20COLD AND DRY CLIMATE COMPILED .pptx
- 1. COLD AND DRY CLIMATE SUBMITTED BY: AVIRAL,DISHA,FARAZ,KUSHAGRA M.ARCH(ENVIRONMENTAL DESIGN)
- 2. In order that the building industry creates more comfortable localities for man to live and work, the different specialists involved should co-ordinate their efforts so that a common goal can be achieved as rationally as possible. Climatological conditions play a very important role in the preparation and the realization of these projects. Therefore the task of the climatologist would then be to assist the technician in reducing the unfavourable elements of the surrounding climate and exploit to the optimum the most advantageous conditions of the environment.
- 3. INTRODUCTION Climate, is the sum total of atmospheric conditions observed in large geographical area over a long period of time. The period of this observation could be 25 – 30 years. Hence, climate can be said to be an average of weather conditions taken over a long time. CLIMATIC ELEMENTS AFFECTING THE BUILT ENVIRONMENT There are five major climatic elements affecting the built environment. They are temperature, humidity, wind, atmospheric pressure and precipitation. CLIMATIC ZONES OF THE WORLD • Tropical zone from 0°–23.5°(between the tropics) ... • Subtropics from 23.5°–40° ... • Temperate zone from 40°–60° ... • Cold zone from 60°–90° CLIMATIC ZONES OF INDIA • Hot and dry • Cold and wet • Cold and dry • Composite • Warm and humid
- 4. INTRODUCTION The 6 climatic zones are summarized in the form of a chart, which gives a general view of each zone at a glance, and facilitates comparisons between them. The brief information on the main climatic features is sufficient to understand the principal requirements of climatic design, such as the need to decrease or increase solar heat gain, provide ventilation or wind protection, store heat and/or absorb moisture, to name only a few design factors.
- 6. COLD AND DRY CLIMATE The cold and dry climate is characterized by: • Climate that is very cold and the precipitation is too low to sustain any vegetation at all, or at most very scanty shrub. • Cold desert climates are typically located in temperate zones, usually in the rain shadow of high mountains, which restrict precipitation from the westerly winds. • Regions that lie in the cold climate zone are situated at high altitudes. • The temperatures range between 20–30 ºC in summers; while in winters, it can range from -3 ºC to 8 ºC, making it quite chilly. • Cold climate requires buildings to have appropriate insulation and infiltration to resist heat loss, and promote heat gain by directly admitting and trapping solar radiation within the living space. • Solar radiation is generally intense with a very low percentage of diffuse radiation.These regions frequently experience snow. COLD AND DRY CLIMATIC ZONE IN INDIA
- 7. PLACE OF THIS CLIMATE TYPE- LEH,LADAKH Ladakh region is at the highest altitude, belongs to the Tibetan Buddhist sphere, western neighboring region is Kashmir. Ladakh lies on the rain shadow side of the Himalayan, where dry monsoon winds reaches Leh after being robbed of its moisture in plains and the Himalayan mountain. The district combines the condition of both arctic and desert climate. Therefore Ladakh is often called “Cold Desert”. The graph shows the daily variation of meteorological paramteres over the year in Leh. Climatic zone: Cold and sunny LEH Location: Leh housing colony(LADKH) Building site: Flat Type of building: Single storey house Occupants: 5 adults, 3 children Livestock: 4cows Building materials Plinth: Stone masonry Floor: Compacted earth with cow dung finish Walls: Unburnt bricks with mud mortar plaster and cow dung finish Roof: Timber substructure with insulating grass layer covered with mud (Ladakhi roof)
- 8. CLIMATE THROUGH THE YEAR January, February and December: One of the coldest times of the season. The nights are chilling and temperatures hover around -20 C. Days are still bearable with 2 C as average temperature. March and April: March is colder than April. Temperatures hover between 6 C in the day and - 5 C in the night. April is still better and day temperatures go up as much as 12 C. There is still the occasional snowfall that further dips the mercury dom. May, June, July and August: Temperatures area pleasant 16°C during the day and a barely manageable 3 C in the night. The breeze still carries the winter chill and one may feel the bite if sitting in shade for too long. June is when the mercury really kicks up and temperatures soar up to 21 C (day). September ,October and November:All through September the weather is somewhat similar to may.The days are a lovely 20-22 C and all of Ladakh is rinsed by ample sunshine.The nights are back to being bitterly cold .The months of October and November again are too cold.
- 9. CLIMATE THROUGHOUT THE YEAR
- 10. SUN MOVEMENT The sun's movement through the day and through the year is one of the most crucial environmental factors to understand when designing high performance buildings. TOPOGRAPHY: • Ladakh is land located between two mightiest mountains ranges karakoram in north and great Himalayas in south. Ladakh has its own range, ladakh range and zanskar range • Dras, zanskar and the suru valley on the Himalaya's northern flanks receive heavy snow in winter, when it melts in the summer it becomes only source of the water for the crops here as there is very less or no rainfall. • Because of thin air in its atmosphere the heat of the sun is more intense then at lower altitude vegetation is very sparse in ladakh except along stream beds and wet lands, on high slopes and in irrigated places.
- 11. SETTLEMENT PATTERN • Leh is the biggest town of ladakh. • The settlements of various sizes are located along the meandering river Indus flowing from east to west. This creates northern settlements facing south to allow maximum sunlight. • The houses are located on slopes of the mountain rather than the plains or valley in order to increase the time duration of sun. • Also they are close to water bodies and Fertile land. URBAN PLANNING : • Leh is typically located on plateau on the northern banks of Indus river. • The old town is on southern slopes of mountains where as newer parts are extended in plains in south west direction. • The highest point of Leh is occupied by houses of nobles and lower side by commoners and main bazzar area. • The vertical staging of buildings ensures the sunlight to all individual houses. • The houses are placed in such a manner so that its 2- 3 sides are shared with other houses to reduce heat loss. • The street pattern of old town is such that it allows maximum solar penetration. • The important streets are laid in north south axis.
- 12. SOIL TYPE The cold arid region of Ladakh has high variability in soil characteristics. Soils of the region are quite distinct from those of other zones due to differences in climate, topography, vegetation and rocks. The paper details soil characteristics along with physiography, geology and climate of the region. Majority of the soils in Leh and Kargil district are sandy to sandy loam in texture and medium to medium-high (e"0.75%) in organic matter with poor water holding capacity. The pH ranged from 5.65 to 10.12 in Leh and pH of Kargil varied from 6.57-9.47. More than 90% samples from both the districts were having pH in the ranges of 7-9. Therefore, majority of the soils in high altitude cold desert regions are alkaline in nature. Soil textures in leh ladakh Types of soil in cold and dry climate
- 13. DESIGN CRITERIA • Site preference • Uses of thicker walls in in structure. • Use of trees as wind barriers along site. • Increase thermal resistance of building. • Increase thermal capacity • Increase buffer spaces • Decrease air exchange rate, Roof insulation, wall insulation and double glazing. • Reduce shading • Utilize heat from appliances • Trapping heat • Air locks / lobbies WINTER SUN SITE PREFERENCE • The orientation of the building should be placed towards south to allow maximum sunlight. • The houses should be located on slopes of the mountain rather than the plains or valleys in order to increase the time duration of sun. • Also they should be closed to water bodies and fertile land • Sun path at allow angle, south to E-W axis. • Solar radiation will penetrate south facing facades at a low angle during winter. N
- 14. • Building will have sloping roof. • Windows will have wooden panels. • Timber paneled wall will be used instead of brick or stone masonry. • Bedroom will be on south west of the house. • Kitchen will be on south east of the house. • Dinning will be on the south. • Bathroom will be on the north west of the house. ESSENTIAL FEATURES IN DESIGNING OF A HOUSE • Sun dried earth block- 300x150x150 mm used for walls of thickness 300 or 450 mm. • Soil available is alluvial soil found in banks of Indus. WALL • A Trombe wall heats air convectively as well as heating the space radiatively. • Vents can be shut at night to keep the convection loop moving in the right direction. TROMBE WALL
- 15. Large opening in wall for light and ventilation purpose. Use of bricks to accommodate cupboards at the inside of the wall. • A simple gable is best. Complicated roof designs invite problems — pine needles, snow and ice can accumulate in nooks and crannies, causing major damage. A simple gable roof is strong and sturdy, and sheds snow easily. • Avoid openings in the roof. Know that each hole you cut into your roof, whether for a skylight, chimney or gable, creates a potential spot for leaks and ice accumulation. That’s not to say you should never add these features to your home; just do so with caution and full knowledge. • Place chimneys near the roof ridge. The highest point on your roof is also the safest place for things like a chimney or vent pipe to go. Since water and snow run down the roof and collect along the eaves, the top is the least-likely spot for snow and ice to build up and cause a leak. • The right window style. Classic single- and double-hung windows, as well as sliding windows, tend to leak more air. Choose awning, casement or fixed windows for a tighter seal. • Well-insulated pipes. Avoid the dreaded pipe-bursting scenario by making sure your pipes are in insulated walls and are well away from unprotected areas. Any pipes near uninsulated areas should be well wrapped with insulation to protect them from freezing. THE ROOF
- 16. Niche for cupboard seen from inside. A dry-stone structure with RC flat slab under construction. RC columns are additionally used to support the longer span. • Install a snow-melting system beneath frequently used paths. This technology can greatly reduce the time and money you spend shoveling and plowing your paths and driveway and make them safer to boot. It’s not cheap, but it may be worth it if you spend a great deal of money and effort on snow removal each winter. • Choose easy-to-shovel paths. Gravel paths may look beautiful, but they are nearly impossible to shovel. Which is fine if you use them only in the backyard or other areas you do not need to access in winter — but for your main paths, choosing a hard material makes more sense. Also remember to make paths wide enough to shovel. • Position railings at every stairway. Even short stairways can become treacherous when they’re covered in ice and snow. Be sure every exterior stairway has a sturdy railing to hold on to — don’t forget the side and back entrances to your house, too. • Provide cover over entrances. A sheltered entrance makes is safer and more comfortable for you — and for visitors waiting for you to answer your door. Think about adding a portico, covered porch or covered breezeway to your home. THE EXTERIOR
- 17. MATERIAL AND CONSTRUCTION Stones • Primary building material is earth and timber available locally. • Both are natural materials offering climatic comfort in condition of Ladakh • They are used due to their high thermal insulating properties. • Mud plaster is applied on walls. • Quartzite stone is used in making lower storey palaces or forts where protection from water is required • Stones are used in lower parts of walls to provide protection and strength.
- 18. FOUNDATION • Stone plinth – 0.6 – 1 meters for two storey buildings. • 3 meters for tower temples. • The upper floors are made of timber planks and timber-joints • Floors of lower storey are made of mud while upper storey by timber • It is observed that traditional construction of earth block and timber was able to offer temperature difference of 40° Cin extreme winters. When outside is - 20 inside it is 20 Crecorded. FLOOR
- 19. • Above the plinth walls are strong with alternating stone layer, as the wall rises it is only the wood frame that is stacked above another wood frame. This distributes mass optimally. • Interiors of wall are finished with mud plaster and lined with wood on account of its good insulation and binding properties. • Resist sliding or overturning during land movement. • Dry masonry construction allow stones to undulate within a flexible wooden framework to allow energy of earthquake to disperse. • Made of alternate courses of dry-stone masonry and wood without cementing mortar. • Layering and interlocking timber and stone provides strength ,stability and flexibility (Earthquake resistant). • These heavy walls allow a good thermal insulation by providing high time-lag of more than 8 hours. This makes the interior of the house cooler in summer and warm in winter for maximum part of the year. KATH KHUNI TECHNIQUE (SPECIAL TECHNIQUE)
- 20. THANK YOU!