What is Low Carbon Climate Resilient Construction?

Low carbon construction essentially involves reducing the carbon emissions during the entire life cycle of the building, right from sourcing of building materials, assembly on site, building operation to demolition. Climate resilient construction includes buildings that respond to predicted climate change and possess the ability to withstand extreme weather events, like natural disasters.

Why is LC-CR Construction Important in Coastal Areas of South Asia?

Low Carbon Climate Resilient (LC-CR) construction is a glaring need in coastal regions as these areas are highly susceptible to the impacts of climate change. According to the IPCC Fourth Assessment Report on Climate Change, in coastal regions of South Asia, large tidal variations, tropical cyclones, coupled with potential increase in regional rainfall are major threats to habitat and can result in serious physical damage to buildings. Hence, the construction sector in these regions needs to address these threats in the form of disaster-resistant construction techniques. In parallel, low carbon footprints of buildings must be ensured by using resources and power as efficiently as possible in construction without compromising on safety, comfort and local lifestyle needs.

How to Carry Out LC-CR Construction in Coastal Regions?

For LC-CR construction in coastal areas, the major areas of concern are:

The primary motive for the design of any building is to provide thermal or occupational comfort to its inhabitants and, in doing so, it must use minimum amounts of energy in its construction and operation. In any area, the local climate provides the key to the shelter needs of people and, hence, climate-responsive design strategies are to be employed if a building is to be operated in an energy efficient manner. After a seasonal analysis of the typical temperatures, humidity, wind speeds and solar radiation that are specific to each season, different types of thermal uses (heating or cooling), ventilation, lighting and wind/rain protection strategies need to be used by an adaptive occupant.

In coastal areas, the seasonal concerns include passive cooling techniques during summer, increased ventilation and effective rain sheltering during monsoons and passive heating strategies during the winter. In response to these seasonal needs, a building designer should use or manipulate the following major design elements or tools to control the thermal environment in the buildings passively without relying on mechanical heating or cooling:

1. Shape of the building: having wind-resistant massing and ideal orientation

2. Fenestration: sizing, positioning and orientating windows to provide optimum solar heat gain, ventilation and natural light

3. Building envelope: providing enough insulation and thermal storage characteristics to the building, enabling it to deal with extreme temperature variations.

4. Solar control: providing shading devices and surface finishes that cut out excessive heat gain from the sun.

5. Cyclone resistance: roof and structural design to resist high wind speeds.

6. Flood resistance: building envelope design to endure excessive rainfall and rising water levels. q