The temperate climate of Kashmir and upper reaches of Jammu, marked by harsh winters with sub-zero temperatures, presents significant challenges for housing in the region. The existing architectural designs are ill-equipped to handle these cold conditions, leading to homes that fail to provide adequate thermal comfort and proper ventilation. This results in cold indoor environments that contribute to increased winter mortality and morbidity, particularly affecting vulnerable groups like the elderly and children. Research shows that prolonged exposure to low temperatures in homes can lead to serious health issues such as raised blood pressure, strokes, respiratory diseases, and exacerbation of conditions like arthritis. The lack of proper insulation and heating further aggravates these health risks, underscoring the urgent need for better-designed homes that can ensure warmth, ventilation, and overall well-being for residents of J&K during the harsh winter months.

Improper ventilation during the winter months is a major health concern in Kashmiri homes, where residents often seal their living spaces to conserve heat. This results in the buildup of stale air having high concentration of CO2 , which can lead to fatigue, headaches, and an increased risk of respiratory infections. Additionally, poor ventilation can aggravate asthma, irritate the eyes, nose, and throat, and trigger allergic reactions. Unlike the tropical plains of India, where natural ventilation is sufficient during winter, cold regions like Kashmir face a unique challenge. With limited airflow and reduced exposure to sunlight due to poor home orientation, the lack of proper air change and sunlight contributes to a sense of tiredness and lethargy, further impacting the overall health and well-being of residents during the cold winter months.

In Kashmir, where space heating and hot water are essential for much of the year, energy consumption in homes is a major concern due to poorly insulated building structures and inefficient water heating systems. These inefficiencies result in significant energy loss, which can be mitigated through the adoption of passive house techniques. By incorporating better insulation, air tightness, and energy-efficient heating systems, homes in the region could significantly reduce their energy consumption. Currently, buildings in Jammu and Kashmir consume around 50% of the electrical energy against 35% at national level, but by designing homes with energy efficiency in mind, there is great potential for substantial energy savings. This shift towards energy-efficient homes would not only lower energy costs but also contribute to reducing greenhouse gas emissions, playing a key role in mitigating climate change and global warming.

The growing trend of designing homes with multi-slope roofs has posed a significant challenge to the installation of solar rooftop systems in Kashmir. While older houses, with simpler and flatter roof designs, can accommodate solar panels effectively, the complex roof structures of newer homes with multiple gables and slopes make it difficult to install solar panels of adequate capacity. These intricate designs are not suitable for the uniform placement of solar panels, which require large, uninterrupted surfaces to capture maximum sunlight. As a result, despite the potential benefits of solar energy, many new houses are unable to utilize this sustainable energy source, limiting efforts to reduce energy consumption and combat climate change. Multi-slope roofs, which feature multiple pitches and angles, can be difficult to work with when installing solar photovoltaic (PV) modules. The irregular angles make it challenging to position the panels optimally for maximum solar gain, which is crucial for generating enough energy to meet the building’s needs. Additionally, multi-slope roofs are often more complex to insulate, fixing of gutters for rain water is difficult, leading to higher costs and potential inefficiencies in energy conservation. Their design also increases construction and maintenance costs, making them less economical in the long run. Moreover, these roofs can pose safety risks to workers such as carpenters, solar technicians, and painters, who may have to navigate steep or uneven surfaces during installation or repairs.

Thermal power plants supply about 43% of the J&K’s electricity, contributing significantly to greenhouse gas emissions. During 2024-25, J&K consumed 21000 million units (MU) of electricity, with around 9000 MU (43%) coming from thermal plants that burn coal. Given that the carbon intensity of electricity generation in India is 0.82 kg of CO2 per kilowatt-hour, J&K is responsible for producing approximately 7 million tons of carbon dioxide annually. This substantial carbon footprint could be greatly reduced by adopting energy-efficient building designs, such as passive houses, which reduce energy demand. Additionally, transitioning to solar energy, with just a 1kW solar plant being equivalent to planting 33 trees, offers a sustainable solution to cut emissions and help mitigate climate change.

JK Green Technologies, a company established to promote energy efficient buildings, solar roof top and mechanical ventilation system in J&K has developed a detailed guideline for construction of energy efficient homes in the cold climatic conditions of J&K. In the larger public interest and to raise awareness and encourage the adoption of sustainable practices in the construction of houses, the same has been placed on the website of the company; https://www.jkgreentech.in/. Following excerpts from the guideline are shared with the engineering community and other stakeholders, so that every individual acts as a catalyst for change, fostering a culture of sustainability and responsible construction in the region:

The house shall be oriented towards south. Wherever site allows, the long axis of the house should be oriented in an east-west direction so that the South side of the house, where most of the windows are located for maximum solar gain during winter, has a greater area than the east or west side. This approach allows more rooms to get sun during the day. In cold climate, winter sun is cheerful. An east-west orientation also optimizes the roof for Rooftop Solar Plant.

The rooms where people will spend most of their time should be on the South side of the house, while utility rooms, bathrooms, closets, stairways, hallways and electrical rooms should be on the North side.

Since Jammu & Kashmir falls within Seismic Zone VI, the region is highly susceptible to earthquakes. The use of beam-column structures is therefore recommended over traditional brickwork, especially for multi-story buildings. Beam-column frameworks provide significantly greater strength, flexibility, and seismic resistance, making them more suitable for withstanding earthquake-induced stresses. These structures enable better load distribution and structural integrity, reducing the risk of collapse during seismic events. Additionally, the use of lightweight Autoclaved Aerated Concrete (AAC) blocks in conjunction with beam-column systems enhances overall construction by improving thermal insulation and reducing dead load, while maintaining non-load-bearing functionality. This combination not only ensures greater safety and performance in earthquake-prone areas but also supports modern construction practices.

AAC blocks are highly suitable for construction in climates with extreme temperature variations due to their excellent thermal insulation properties, having a low thermal conductivity of just 0.17 W/m.K compared to 0.98 W/m.K for dense clay bricks making bricks nearly five times more thermally conductive. In addition to enhancing energy efficiency, AAC blocks are also environmentally friendly, containing approximately 60% fly ash, a recycled byproduct of thermal power plants, thereby promoting sustainable construction practices. These blocks should be installed in such a manner that all RCC beam and column structures (which have a much higher thermal conductivity of 1.58 W/m.K) will be fully concealed within the AAC block work. This approach ensures that no direct RCC thermal bridges exist between the exterior and interior of the building, thereby maintaining continuous thermal insulation and significantly reducing heat transfer across the building envelope. (GRIHA V.2019 Volume 1, Criterian-19).

Small budget houses may be constructed with bricks. However, exterior walls shall be of 14 inch thickness and thermal insulation shall be provided on these walls forming envelope of the house.

Bond beams or tie beams at height of 1200mm (4 feet) from foundation and lintel beam shall be provided to enhance structural stability and prevent cracking of AAC Blocks. Thermal insulation of design thickness shall be provided inside the beams to avoid thermal bridging (IS 6041 and IS 1905-1987).

With a view to restrict the volume of air to be heated during winter and to be cooled during summer, the finished floor height (FFL) shall not exceed 8.5 feet. For buildings designed for large social gatherings like mosques etc where increased sense of spaciousness, improved air circulation and restriction of CO2 concentration is required, the FFL may be increased to 10 feet.

The roof will be designed in such a manner that it supports solar modules for 100% electricity consumption or higher. It shall also support solar water heaters to meet the 100% hot water demand of house. Platforms for solar water heaters shall be provided with necessary water head from over head water tanks right at the construction stage, (GRIHA V.2019 Volume 1, Criterian-8). To meet the increased hot water demand due to occasional over consumption or during chilaikalan, heat pump shall be provided as back up. For budget houses, water boiler (locally known as Steamer) may be provided which shall be well insulated to prevent heat loss. Present practice of using water boiler without insulation is highly energy inefficient. By taking these steps, the building will therefore qualify for Shunya Labeling system. This system, introduced by the Bureau of Energy Efficiency (BEE), is a program focused on promoting Net Zero Energy Buildings (NZEB) and Net Positive Energy Buildings (NPEB) in India. (Refer Shunya Labeling for NZEBs and NPEBs).

The windows shall be of minimum Double Glazed, Argon filled, uPVC type for better thermal properties. To reduce the cost of these windows and for enhanced thermal properties, most of the windows will be non-operable type. In case of failure of mechanical system ventilation shall be provided by few operable windows positioned strategically. The window to wall ratio shall not exceed 60% (GRIHA V.2019 Volume 1, Criterian-10) and window to floor ratio for South faced windows shall be of the order of 15 to 20% (Practice being followed globally in cold climatic conditions)

Budget houses may be constructed with wooden windows, however, these shall also be double glazed. The two glasses of the windows shall be got combined in some local uPVC window manufacturing plant and then fitted in the wooden frames at site.

To mitigate the infiltration of extreme temperatures into the house especially during peak winters, doors should not open directly into it. Instead, a vestibule or anteroom should be incorporated to act as a buffer zone, preventing direct exposure to external conditions. This space can help regulate temperature and humidity before entering the house.

The ventilation to sealed houses having uPVC door and windows shall be provided through a Heat Recover Ventilator (HRV). This will also prevent high CO2 concentration and mould formation due to condensation inside house, which are serious health hazards. Duct work for same shall be provided during construction phase. HRV supplies fresh air, and also removes moisture and CO2, the level of which should not exceed ambient+500 PPM (GRIHA V.2019 Volume 1, Criterian-19).

The buildings designed for large social gatherings like mosques etc., shall be provided mechanical ventilation irrespective of the fact whether windows are uPVC type or wooden. The recent studies have revealed that CO2 concentration in mosques during peak occupation and with windows closed for air conditioning, generally exceeds 4000 PPM, which is bad for health.

The windows on South side shall be large enough for maximum solar gain during winter. The windows on Western side shall be kept small to avoid overheating in afternoons during summer. On Northern and Eastern side normal sized windows as per convention and aesthetic requirement shall be provided. Deciduous trees may be planted on Western side. These trees shade Western windows during summer and shed leaves during winter thereby allowing winter sun to enter the house when it is most needed.

Thermal insulation of design size shall be provided under the false ceiling for restricting heat loss during winter and heat gain during summer.

Wall insulation and panels to conceal the insulation shall also be provided for restricting heat loss during winter and heat gain during summer through the walls. However wall panels and false ceiling panels with high Volatile Organic Compounds (VOCs) shall be avoided. VOCs are a group of chemicals that can vaporize into air. Exposure to VOC vapors can cause a variety of health effects.

In case attic of house is not built up for living, its floor may be treated as envelope and the same may be insulated. This step will reduce the area of insulation and save on cost. It will also enhance the thermal property of the top envelope of the house. However, for houses designed with common hall for social gatherings on the attic, from which sloping roof is visible, the insulation may be provided directly under the roof.

Balcony, Varandah, Window Shields constructed by RCC Slab extensions (Thermal conductivity; 1.58 W/m.K) act like fins of radiator. These dissipate internal heat of the house to atmosphere during winter and conduct solar heat into the house during summer. These shall be avoided.

The insulation for various building components shall be designed as per Energy Conservation and Sustainable Building Code 2024 (ECSBC-2024).

The space heating shall be through underfloor heating. This type of heating doesn’t use forced air to distribute heat. It is generally better than convection fans for people with allergies because it doesn’t circulate dust and allergens, and it can help reduce moisture. Underfloor heating provides even, comfortable warmth that rises from the floor. Thermodynamics fully supports underfloor heating as natural convection, maintains a constant gradient from floor to ceiling with radiation supporting the convection. In case of power failure, the concrete cover over the heating coils dissipate heat slowly.This cover, therefore acts as thermal mass for regulating space temperature during power failures. In cold areas blood vessels in the extremities, such as the hands and feet, constrict. This reduces the blood flow to these areas, as such we feel very comfortable if our feet and hands get warmed. The underfloor heating shall require 4” of floor height for insulation and concrete covering.

An independent Electrical Room of minimum 6 feet X 6 feet size shall be provided to accommodate; solar equipment, power distribution panel, voltage stabilizer, batteries etc. Sufficient ventilation to the room shall be provided for removing the heat dissipated by the electrical equipment inside the room. Shafts from the electrical room to the upper storey of house shall be provided for routing of cables.

Every effort shall be made to implement other green building principles like; tree preservation and plantation, site planning, water efficiency, rain water harvesting, use of sustainable materials, waste management, and encouraging a green lifestyle etc.

In conclusion, the adoption of these energy-efficient building guidelines is not just a technical necessity but a moral imperative for the sustainable development of Jammu & Kashmir. By integrating passive design strategies, renewable energy systems, proper insulation, and modern ventilation techniques, we can significantly improve indoor comfort, reduce energy consumption, and mitigate health risks associated with cold climatic conditions. JK Green Technologies urges all stakeholders; engineers, architects, builders, and homeowners to act as agents of change by implementing these best practices in every new construction. Together, we can build homes that are not only resilient and energy-efficient but also aligned with the broader goals of environmental sustainability and climate action, paving the way for a healthier, greener, and more self-reliant future for the region.

The purpose of this guideline is to raise awareness among Engineers, Architects, Contractors, and House Owners about the design of energy-efficient homes suited to the cold climatic conditions of J&K. The recommendations provided herein are meant to serve as general guidelines for achieving energy efficiency in such environments.

However, it is essential that these recommendations be implemented only after thorough consultation with a qualified Architect or Engineer to ensure that the building’s structural integrity and other critical design factors are not compromised. Each project may have unique requirements, and professional oversight is necessary to achieve optimal results while maintaining safety and compliance with local building codes.

Er. Bashir Ahmad Dar, Managing Director, JK Green Technologies, former Secretary Technical, JKPDD/Managing Director, JKPTCL

© Greater Kashmir