We say that our homes are our shelters. Shelter is a habitation that offers us comfort from cold, heat, rain, sun and snow. Every home deserves to be called a shelter only and only if it meets all these requirements. Our area which is a part of vast Himalayas is particularly cold. The common word on the mouth of every individual during the long winters is that our houses (that make our home) are cold. The brief summers are also hot with the increase in the humidity levels wherein the houses cannot ventilate out the humid hot air. We build our houses such that snow and rains are protected against by tin pitched roofing. We all can safely say that our houses do not meet the requirements of a proper shelter.
Our house construction has evolved over years from the use of traditional clay adobe bricks to modern day use of fire kilned brick. The evolution has also happened in use of rampant concrete and cement in every type of construction. The use of steel rebars and modern day use of aluminum claddings and aluminum and steel window frames is also becoming popular. Our houses are our entities and they need to be visualized from the perspective of proper use of materials. We invest enormous amount of money in their construction in terms of materials and still find little comfort in such houses. At the same time, the investment on strength of house is paramount and this would require use of building materials that offer good strength for stability particularly during earthquakes.
So we at IUST Awantipora tried to explore various options that are available in making our housing structures comfortable; moreover adhering to the requirements of stability and strength of the structural housings. The work points out to use of the available materials but with good structural and architectural design. At onset the first word to the public at large would be to consult a building designer who has knowledge of earthquake resistance as well as thermal comfort in houses. It needs to be clear that house features like house orientation, amount of shading, type of roof with its roofing material and coatings and its pitch or angle of inclination, type of windows and window frames and window glazing’s, amount of reflective paints on walls, size of openings or windows and ventilators and many more things are critical in a proper housing.
Our houses need to passively imbibe energy from the atmosphere in proper quantity and at the same time they should not leak out energy to the outside atmosphere in quantities not desired. During winters, the sun is south facing or southwards and thereby our windows need to trap maximum amount of solar energy during such season. The windows and their glazing’s needs out orientation in order to allow the infrared radiation to be trapped. The inclination of the sun is at an angle of around 33 degrees in Srinagar city and the windows could be inclined at an angle to trap the solar energy. These principles have been adopted in many countries and housings. At the same time the housings need to have less exposure northwards but with proper ventilations. Accordingly, the summer rooms could be north facing which would have good ventilation and shadings as well on that face. The winter rooms could be south facing.
The rooms need shading with trees and plantation for hot summers where in the sun radiation falls from the east in morning. The early morning heating is critical during summers. So it is advised to shade the houses on eastern side and limited on the southern side. The windows on western side for summer sun can have louvers or shaders but they need to be rolled up for winter sun. On cold winter days with limited solar radiation, the windows on East, West and North side can be availed with wooden outer shutters as was present in old housings. The same can be provided with simple small ventilators with glazing’s for lighting and ventilation.
The house windows leak out 30% of the energy from the houses. The air-conditioned room leaks out more energy with the increase in the thermal gradient between the exterior and interior of the housing. There is a rich wind draft called ’taerchatt’ in kashmiri that flows from the windows and doors during winters. This happens due to absence of the silicon and rubber sealings on window panes and doors; the cost of which is negligible. The windows once constructed with wooden frames finds it difficult to open after closing them during winters due to ingress of moisture as we commonly use unseasoned wood. With the result, we call the carpenter during summers to remould the window frames which fit but actually leave an air gap. This air gap leads to wind draft/taerchatt during winters as well. So, achieving the proper window frames for winters in wood has become challenge.
The present day houses are recommended to have UPVC paneled window frames for preventing winter wind draft. Secondly, the window glazing is in athin glass that is unreflective. The window glaze conducts all the outer temperature and cools down our rooms during winters. During summer the same window glazing heats up the room and even with the use of air-conditioning in a room, the loss of energy is tremendously high. The houses need to be build with reflective glasses for summers only if sun radiation is heating the room in large quantities. However, use of reflective glasses on South side for winter sun would not be desired in our region.
The outer walls of the house are mostly in bricks. The use of cement plaster on outer walls is not desirable as it offers maximum cold contact after aluminum and steel among common building materials. It would have been better to clad our housings on outer face with any thermal insulating material and with sun reflective coatings or colour. The exterior insulation is the best one can offer to a structure. This can be done post construction as well and years after construction as well. It is most desirable for proper housing design for maximum thermal comfort. There are many materials that offer thermal insulation, both engineered and non-engineered. It is advisable to consult the experts before proceeding on the nature of thermal insulation as ‘one model does not fit everywhere’.
The ground floor is usually layed on mud or brick or stone or concrete flooring. These all offer conduction of cold temperature from the soil underneath and some loss of heat from rooms happens from the base flooring as well. The thermal insulation in base flooring is must with layers of water-proofing/barrier layers and as well as insulation layer. The roof design for pitched roofs needs to be perfectly insulated. It is a general trend in market to use glass wool or some poor quality of mineral wool for insulation. These should be avoided as they hardly offer any insulation. The variety of insulating materials of which polyurethane based foams are available are seen to among best for roofing insulation. The use of reflective coatings below roof (which is silver coloured foil) is advisable for hot areas and does not contribute to thermal insulation for winter cold. The use of it alone is of no specific purpose in our region but has become a norm. It is advised that wall insulation’s in mineral wool should be avoided from inside as our rooms are humid and closed during winters and there are more chances of condensation and subsequent fungal growth inside.
We have observed that the use of wooden paneling has become a norm in all our housings. It is again advised that use of wooden paneling only adds a combustible material which burns rapidly and does not contribute to thermal insulation or thermal comfort. This has been proven in studies performed in our work. It has been seen that the amount of electricity that is required in heating our houses during winters is tremendous given that there is limited availability of other sources of energy like coal, oil for conventional and semi-conventional heating gadgets. The cost of heating and cooling gadgets also increases with their efficiency from blowers, heaters to radiators, coolers, air conditioners, HVAC systems. Still with the increase in efficiency the electricity is required to be pumped continuously in order to run and maintain a comfortable temperature.
Without passively designing our houses as detailed above in points, the worth of all heating and cooling techniques is net nil and with the result our houses never seem to heat up during winters. Even if they heat up, even half an hour of putting off the heating appliances pulls off all the heat from such houses. Conventional use of hamam is not a viable and feasible solution in multi-story house as it does not cater to every room. Besides, it involves burning of wood, the resources of which are not being replenished rapidly.
The building of houses for winters in kashmir is not difficult if properly supervised and construction is done as per set rules and principles of construction. The involvement of trained supervisors is critical and needs to be encouraged.
(The Author is working in areas of fire engineering and thermal insulation’s of buildings. He has obtained his PhD from IIT Roorkee in fire engineering of structures and is presently working at IUST Awantipora as academician in Department of Civil Engineering. He can be contacted at: [email protected] for comments about this article)
