Beating the Heat in Urban Planning

Cities are increasingly seeking building materials with a positive environmental impact — making cities cooler in more ways than one.

Urban living has always had a unique set of challenges, including gaining access to resources, high population density and aging infrastructure. Urban areas are also, by their very nature, hotter and more vulnerable to environmental forces. The sun bakes rooftops, moisture becomes trapped, damaging homes and other buildings, and ultraviolet radiation damages materials while making it difficult to keep living and working spaces comfortable.

Unlike rural areas, which are more spread out and able to use the landscape in beneficial ways, urban centers are crowded and can often only build upwards. More and more cities are requiring new construction projects to incorporate “green” materials that reflect heat, control air flow and protect against the invisibly damaging rays of the sun. The good news is that these materials exist, they’re extremely effective and the investment pays off — big time. From the roof down The “perfect storm” of natural forces that cause buildings and infrastructure to fail are heat, moisture and radiation. Cutting-edge building materials offer ways of controlling these forces — minimizing the damage they can do and making buildings last longer, be healthier and more comfortable and cost less to maintain.

It all starts with the roof, where the heat is typically absorbed. Many cities become “heat islands” because of the density of the population and the coverage of land by buildings, resulting in an overall temperature increase compared to nearby areas — up to 27 degrees in some cases. This excess heat wears on building materials and causes an increase in heat-related medical issues (heat being the main weather-related cause of death in the United States).

A new wave of roofing materials offers sustainable solutions. 3M, for example, has developed Cool Roofing Granules. Used in roofing shingles, the granules reflect part of the solar energy typically absorbed by traditional roofing materials. With cities like Los Angeles mandating cool roofs as part of their revised building codes, materials like this are not only beneficial to both the builder and those who will utilize the buildings — they’re increasingly required. High and dry Air flow and humidity also impact the comfort and health of individuals (incidents of sick building syndrome are typically linked to poor ventilation), as well as the maintenance and useful life of a building. The construction industry has long used vapor barriers to control air flow and prevent excessive moisture, and cutting-edge air barriers and building envelope products like those offered by 3M prevent uncontrolled air flow and buildup of condensation. Sun control A major challenge for both residential and commercial structures is managing sunlight. No one wants to work in a dark, windowless space, but sunlight increases interior temperatures while ultraviolet light damages surfaces and fades colors.

Again, new products offer a sustainable solution. Window Films, developed by 3M, offers an affordable and effective “sun control,” which helps block harmful heat and UV rays while allowing sunshine in (also offering increased security and safety, glare prevention, increased privacy and more efficient heating in the colder weather). Window films can be easily applied post-construction, instantly upgrading a home to a greener, more energy-efficient and more comfortable space.

Cities aren’t going to become less crowded, and sustainability is only going to become more important — and increasingly required by the zoning codes in cities where climate is already an issue. With smart use of advanced materials on the roof, on the windows and on the walls of new and existing buildings, the future of the urban center is cooler in every sense of the word.