Construction Materials that Increase Resilience to Natural Disasters

Construction Materials that Increase Resilience to Natural Disasters

Eucalyptus forests in Australia are known to burn periodically. It is the trees’ way of ensuring propagation, as its fruits – known as gumnuts – have an insulating layer breaks down with the heat of the fire. Once they open, the burnt soil is covered with seeds, initiating a process of forest renewal. Glenn Murcutt, an Australian architect, has created a body of work rooted in the country’s landscape. His innovative houses embrace the possibility of frequent fires, including elements that allow for fire control with the least possible loss. In short, the houses are built with very non-flammable materials, always have huge water reservoirs, and a “flood system” that allows the building and its immediate surroundings to be spared in the case of a forest fire.

However, what the Australian situation has shown is that eucalyptus forests aren’t the only ones burning; its tropical forests are also being burnt, devastating large portions of the Australian territory. Unfortunately, this country is not a global exception. With the intensification of the climate crisis, natural disasters have become more frequent and more severe. Sadly, it will only intensify if nothing is done. This bring us to ask the question: as architects, are there ways of mitigating this?

According to the latest IPCC report, what seemed like a dystopian future is now our reality. “Devastating droughts, extreme heat and record floods are already threatening the food security and livelihoods of millions of people. Since 2008, catastrophic floods and storms have forced more than 20 million people a year to flee their homes.” Even though the construction industry has a responsibility to lower carbon emissions, we nevertheless will have to adapt to an extreme planet that will require resilience. According to this report by the Organization for Economic Co-operation and Development (OECD), infrastructure networks will be affected by the physical impacts of climate variability and change, but will also play an essential role in building resilience to these impacts. Extreme events illustrate the extent of this potential exposure. Along the same lines, the IPCC estimates that adaptation to climate change, in developing countries alone, will reach US$ 127 billion by 2030 and US$ 295 billion by 2050.

Permeable surfaces to control flooding

The intense urbanization of large cities around the world has sealed huge amounts of land and often channeled and diverted waterways. During heavy rain, it is common for drainage systems to fail and floods to occur, bringing destruction, damage and risk of life and disease to residents. If heavy rains are only going to increase – along with the rising level of oceans – it is essential to find ways to optimize water use. Launched by NACTO (National Association of City Transportation Officials), the Urban Street Stormwater Guide illustrates a vision of how cities can utilize one of their best assets (their streets) to address resilience and climate change while creating enjoyable public spaces. The guide adds social and economic value to cities and protects resources through reconnection with natural ecological processes.

Rain(A)Way, in turn, develops products that solve urban water problems. Its tiles store rainwater in a visible and original way, allowing surfaces to delay the infiltration of water into the soil or urban infrastructure by reducing their overload in an extreme weather event. There are also materials that address these issues. For example, AquiPor is a type of permeable concrete that allows water to flow through it, infiltrating the soil, while filtering dirt, debris and particulate pollution inherent in urban stormwater runoff, managing it in an ecological and efficient manner. In addition, the material uses an inherently low-carbon cement that both requires a fraction of the energy and emits a fraction of the CO2 of traditional concrete.

Heat reduction methods

One of the most challenging parts of the climate crisis will be mitigating increasing temperatures in a sustainable way. It should be noted that cooling buildings is much more complex than heating them: any form of energy can be converted into heat, and our bodies and machines generate heat naturally, even in the absence of active heating systems. Cooling does not benefit from spontaneous generation, often making it more difficult, more expensive, or less efficient to implement. ArchDaily has covered some of these strategies in the past, specifically focusing on materials that lead to passive cooling and natural ventilation techniques, such as cross ventilation or the chimney effect.

However, focusing on more robust and insulated enclosures can also reduce cooling demands in buildings. One of the products addressing this issue is Soldalit-Coolit, an innovative sol-silicate ink designed to reduce solar heating when using dark color tones. Coatings with Keim Coolit technology have a specific pigmentation and therefore absorb less solar energy. They visibly reduce the thermal absorption of facade surfaces and avoid temperature-related stresses on the rendering structure.

Another method that can be used in urban centers are green roofs, which additionally can help to absorb rain. For building occupants, the added rooftop vegetation serves to reflect most of the direct sunlight, rather than having the building absorb it. In addition, the moisture present in the substrate prevents the structure from heating up, therefore saving energy. In arid climates, increased thermal inertia will increase comfort by reducing temperature fluctuations in interiors. Furthermore, green roofs generally qualify as potentially usable and extremely pleasant green spaces. But the advantages are not just for private use: especially in large and dense cities, creating green roofs can mitigate urban heat islands.

Rapid reconstruction and self-reparation

Regardless of the solutions outlined so far, severe weather events are bound to occur anyway. It is therefore vital to build structures that can be quickly rebuilt, allowing residents to go back to normal as soon as possible. Modular constructions and prefabrication are two ways of going about it, as they allow buildings to be assembled in a short period of time, with less consumption of raw materials and greater predictability throughout the process.

Lastly, technology can also provide countless other possibilities that we can’t even imagine yet. For example, the ability of concrete and asphalt to self-repair can significantly reduce losses and inconveniences.

It is important to keep in mind that the construction industry, in addition to becoming resilient, has a huge role to play in changing the course of climate change. A lower carbon footprint and/or recycled materials should be used whenever possible. The window of opportunity for climate action is quickly closing on us, and in addition to adapting, we must make conscious decisions for the future.