In the context of the International Day against Climate Change, the Spanish National Association of Ready-Mix Concrete Manufacturers (ANEFHOP) has come up with five factors with which concrete contributes to improving the sustainability of buildings in the different construction stages.
“The use of ready-mix concrete at the plant, compared to other materials used in the construction of buildings, results in significant energy savings for numerous reasons, and it provides us with new alternatives in the current situation with the increase of costs and the trend in the last few years to cut down on the carbon footprint and promote a greener sector”, acknowledges Carlos Peraita, the general manager of ANEFHOP.
- Energy saving
Firstly, in the design stage, the use of materials with high thermal inertia, such as concrete, combined with the right orientation of the buildings, helps to make the most of solar energy in areas with high thermal daily amplitude. Housing built with concrete can absorb the solar energy through the windows and store it in the large body of the slabs, walls and ceilings, which can only be released when the air temperature drops to values lower than these elements, through the mechanism of radiation. This phenomenon can save a significant amount of energy for the inhabitants of this housing.
Studies describe how the manufacturing solution with the concrete wall enclosure, compared to the traditional brick enclosure solution, also has numerous advantages such as fire protection, good soundproofing and significant energy savings on the air conditioning of the building.
- Local products and transportation
In the construction stage of the building, concrete is a local material, manufactured near the work site, with local materials too, which contributes to energy saving in the transport.
When the building is being used, the most important characteristic is that all the concrete features are passive, that is to say, permanent and inherent to construction with structural concrete, without having to carry out any maintenance work or specific preservation work, which therefore avoids incurring significant costs. This all contributes to the high durability of the structures built with concrete against environmental factors compared to other building solutions.
Finally, in the demolition stage of a structure, concrete has the advantage of being a material that can be 100% recycled very easily compared to other construction materials. A common application is to use the recycled aggregate that comes from demolished concrete to make new concrete. The Spanish Code on Structural Concrete states that this recycled aggregate can be used as a substitute for coarse aggregate in replacement percentages of up to 20% in weight and it can be used to manufacture mass concrete and reinforced concrete with a characteristic strength of no more than 40 N/mm2, it cannot be used to make prestressed concrete.