The function of concrete in reducing urban heat in San Jose

As more cities across the US are looking to become more energy efficient, reduce greenhouse gas emissions, and improve their air and water quality, many urban areas are evaluating the impact of the heat island effect. The artificially increased temperatures of urban heat islands have various negative impacts, and growing cities like San Jose are looking to proven strategies to mitigate it. Commercial concrete contractors in San Jose play an instrumental role in combating this phenomenon through their use of concrete as a cool pavement.

The Heat Island Effect

The Heat Island Effect refers to the higher temperatures in urban areas as compared to nearby rural spaces. These temperatures can be up to 5.4 degrees (F) hotter than surrounding areas during the day, and up to 22 degrees warmer at night. Urban heat islands are a consequence of the way the built environment is constructed, from the materials used in construction to how the city itself is designed and developed, which leads to the absorption and trapping of solar energy. The heat island effect negatively impacts urban areas by increasing peak energy demand and utility costs during hot days, contributing to air pollution and greenhouse gas emissions, and even affecting the incidence of heat-related health conditions and the quality of a city’s water. There are multiple ways to mitigate the heat island effect, including incorporating more trees and vegetation in a city, employing smart development practices, and utilizing green roofs and cool pavements that reflect more solar energy.

Concrete as a cool pavement

As a part of a multi-faceted strategy, cool pavements can have a significant impact on reducing temperatures in urban areas. In most cities, pavement constitutes a large portion of urban surface area in the form of roads, parking lots, and sidewalks. Traditionally, these paved surfaces absorb light and solar energy, heating the air above it. Cool pavements, however, are those with an increased solar reflectance or that use permeable material and so work to mitigate the heat island effect. Concrete is an ideal cool pavement type due to its high solar reflectance, or albedo, which measures the percentage of solar energy reflected by the surface and is the main property by which cool pavements are tested, along with their thermal emittance. As a paving material concrete scores well on the Solar Reflectance Index and also has the potential to have increased permeability. Pervious concrete applications such as foam concrete or concrete blocks or pavers allow air, water, and water vapor into the voids of the material and the ground beneath which in turn aids in lowering temperatures through evaporative cooling.

Conco is a leading supplier of concrete services for the Western United States.  As one of the leading commercial concrete contractors in the Bay Area, we have been involved with large-scale projects in the area including the new 49ers Stadium.  Our concrete services include commercial, educational, parking and other construction development as well as public works projects and highways.