Climate change is one of the most pressing issues of our time. And for good reason. The effects of the climate crisis are not only visible in natural habitats, but also in urban environments. The construction sector has a significant role to play in this dynamic. Summits such as the COP, where negotiations are held to strengthen the plans put forward against the climate crisis and to implement these plans with concrete steps, highlight the importance of the effort to reach net zero carbon and the challenges facing developing countries affected by increasingly devastating natural disasters. Possible paths for development include actions at different stages and scales, from optimizing green spaces for urban heat control to using local and innovative building materials to minimize carbon footprints or enacting laws that help create more sustainable urban and natural environments.
One of the less visible effects of climate change in cities is the intense heat waves that affect millions of people. Densely populated cities are particularly at risk due to the heat island effect. In combating these impacts, cities have the advantage of implementing a variety of strategies to keep their residents safe: strategically using green infrastructure, including passive cooling systems, creating climate shelters, and implementing practices that help people live there safely during the warmer months.
Rising sea levels threaten the livelihoods of more than 410 million people living in coastal cities. Because these cities are a magnet for residents, tourists, and businesses, encouraged by the proximity of ports and shipping, land use in these areas tends to favor density, with high-rise buildings and heavy traffic taking up most of the available space. This strategy has proven ineffective in reducing the impacts of coastal erosion and natural disasters that affect areas, such as recurring hurricanes and floods. Architects and designers are looking to natural and local solutions to rebalance coastal ecosystems, such as recreating mangrove forests, creating habitat breakwaters, or building floating structures offshore.
The COP 27 and the 2022 United Nations Conference of the Parties was an international conference held in Sharm El Sheikh, Egypt, to encourage countries to take effective measures against climate change and to ensure that global temperature increase remains below 1.5 degrees Celsius. This goal is largely reflected in the construction sector, as it is responsible for a large percentage of global emissions. The main challenge is summarized in the goal of achieving net zero carbon emissions.
Innovation is likely to be a big part of the fight against climate change. The construction sector is working to develop more energy-efficient products, both in manufacturing and in operations. Transporting construction materials to the construction site accounts for a significant portion of the energy used and CO2 emissions produced by the construction industry. There are a number of things that can be done to prevent this:
• Plan routes in advance
• Plan work to avoid multiple site visits and semi-full or empty truck trips
• Pack each vehicle tightly to reduce the number of trips
• Use local material suppliers
Natural ventilation is a more economical alternative to air conditioning, and it also reduces energy use and CO2 emissions. Again, natural light reduces the need for artificial lighting during daylight hours, which in turn reduces energy use and carbon emissions. In order to build energy-efficient buildings, daylight needs to be considered as part of the design.
The total impact of all greenhouse gas emissions attributed to the materials used in the construction of a building is known as the embodied energy of the building. One of the most effective ways to reduce carbon over a lifetime is to design long-lasting buildings using materials that will last without needing to be replaced.
In densely populated areas such as cities, rooftop gardens can be designed to eliminate pollution and provide a haven for wildlife. Plants convert carbon dioxide into oxygen and release it back into the atmosphere, helping to reduce smog and pollution.
The use of solar panels, wind turbines, heat pumps and electric heating or cooking systems stand out as important strategic elements in combating the climate crisis.