What makes concrete a sustainable building material?

Analysing how concrete can be a sustainable building material

Sustainable building material is an ongoing trend in the construction industry. It not only reduces the costs but it gives another big incentive by reducing the carbon footprint and keeping a clean environment. Concrete is one such building materials that has created its own space in sustainable building material due to its versatile applications and qualities. This article will describe how concrete can be a sustainable building material.

Concrete is an all-time friendly substance. Its durable and versatile applications make its usage ubiquitous throughout the cities. From raw material production to demolition, concrete makes a natural choice for sustainable home construction. It is also a cementitious material that meets or exceeds the functional performance capabilities of ordinary Portland cement by incorporating and optimising recycled materials, thereby reducing consumption of natural raw materials, water, and energy, resulting in a more sustainable construction material, describes Rohan Agarwal, Managing Director, Geopreneur.

Some benefits of using concrete for sustainable building material can help in resource efficiency; the predominant raw material for the cement in concrete is limestone as its the most abundant mineral on earth. This helps maintaining long-lasting, rust free building that are durable. The use of concrete increases the life span by double or triple of other common building materials. The other advantage includes the thermal mass. They are highly energy efficient because they take advantages of concrete thermal mass ability to absorb and retain heat. Although new technologies are constantly being developed to complement current practices in creating greener structures, the common objective of green buildings is to reduce the overall impact of the built environment on human health and the natural environment by efficiently using energy, water, and other resources,protecting occupant health and improving employee productivity and reducing waste, pollution and environmental degradation. However, Agarwal suggests, the concept of concrete is very new for the Indian market and it is essential to create as much as awareness as possible about the benefits of concrete to encourage developers to start using it over the regular cement.

Concrete is a perfect option for construction believes Kishor Pate, CMD, Amit Enterprises Housing Ltd. He says, Concrete is an eminently environment friendly building material during the entire span of its life cycle, beginning from its production as a raw material right until it is demolished. This renders it the perfect and obvious building option for the construction of sustainable homes.

Concrete is used in erecting buildings which are not subject to rust, burn or otherwise degrade. In fact, buildings built with concrete have twice or even thrice the life-span of buildings erected with the use of any other construction material. Life spans for concrete building products can be double or triple those of other common building materials.

The use of concrete in forming the foundation, floors and walls in a building renders the building extremely energy-efficient, since concrete has the advantage of being able to absorb and retain heat. In other words, people who live in homes built of concrete save significantly on both cooling and heating bills. In a concrete building, one can install air conditioners of lower capacity, resulting in significant electricity savings. Also, concrete reduces the incidence of processes that result in urban heat islands. When concrete, which is inherently light in colour, is used in building pavements and roofs, the end result is that less heat is absorbed and more incoming solar radiation, informs Pate.

Finally, concrete as a building material result in the least waste of raw building materials, as it can be manufactured and used in the actual quantities required to build a building or other project. Once a building or structure built of concrete has completed its life-cycle or fulfilled the purpose for which it was erected, the concrete can be recycled into aggregate which can then be used to lay concrete pavements or provide an underlying base for roads.

Although the production of concrete leads to considerable CO2 emissions, concrete can still be a good choice from an environmental point of view, believes Yatin Joshi, Head-Alccofine, Ambuja Cements Ltd. Citing reasons he adds, Concrete is strong and has a long service life. These qualities combined contribute to low maintenance costs. Concrete has a higher thermal heat capacity than lighter building materials. This quality can be used to reduce the amount of energy for heating and cooling during the life time of a building.

On the other hand concrete restricts a fire, and so reduces the risk of environmental pollution. It provides built-in fire protection – there is normally no need for additional measures. It can resist extreme fire conditions, making it ideal for storage premises with a high fire load. It does not produce any smoke or toxic gases, so helps reduce the risk to occupants. Concrete is easy to repair after a fire, and so helps businesses recover sooner.

Concrete pavement roads are bright examples of sustainable construction over bitumen roads. Concrete roads have stood test of time for decades, assures Joshi.

Alccofine micro materials improves the quality of concrete manifolds and make it more durable and sustainable.

Shridhara.C.N, Head-Technical and Marketing, Preca Solutions, says, Concrete is a friend of the environment in all stages of its life span, from raw material production to demolition, making it a natural choice for sustainable home construction.

Here are some of the reasons why concrete is a sustainable building material according to the Portland Cement Association and the Environmental Council of Concrete Organisations:

Resource efficiency:
The predominant raw material for the cement in concrete is limestone, the most abundant mineral on earth. Concrete can also be made with fly ash, slag cement, and silica fume, all waste byproducts from power plants, steel mills, and other manufacturing facilities.

Durability:
Concrete builds durable, long-lasting structures that will not rust, rot, or burn. Life spans for concrete building products can be double or triple those of other common building materials.

Thermal mass:
Homes built with concrete walls, foundations, and floors are highly energy efficient because they take advantage of concretes inherent thermal mass or ability to absorb and retain heat. This means homeowners can significantly cut their heating and cooling bills and install smaller-capacity HVAC equipment.

Reflectivity:
Concrete minimises the effects that produce urban heat islands. Light-coloured concrete pavements and roofs absorb less heat and reflect more solar radiation than dark-coloured materials, such as asphalt, reducing air conditioning demands in the summer.

Ability to retain storm water:
Paved surfaces tend to be impervious and can block natural water infiltration into the soil. This creates an imbalance in the natural ecosystem and leads to problems such as erosion, flash floods, water table depletion, and pollution.

Pervious concrete is a special type of structural concrete with a sponge-like network of voids that water passes through readily. When used for driveways, sidewalks, parking lots, and other pavements, pervious concrete can help to retain storm water runoff and replenish local water supplies.

Minimal waste:
Concrete can be produced in the quantities needed for each project, reducing waste. After a concrete structure has served its original purpose, the concrete can be crushed and recycled into aggregate for use in new concrete pavements or as backfill or road base.

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