PABLO GARCÍA-RUBIO | Tungsteno
The climate crisis has brought the criterion of sustainability to the forefront in many sectors with a large environmental impact, such as transportation, fashion and construction. This last sector is rethinking the way in which buildings and structures are constructed in order to minimise emissions both during the erection process and throughout the life of the building. But sustainability is not only about avoiding emissions that harm the environment; it is also about designing and constructing buildings that are healthy for their inhabitants, their users and even the people who build them.
For years, many materials and techniques have been used without knowledge or consideration of their impact on people's health. Such was the case with lead, asbestos or various additives in wall coverings, insulation or paints which, over time, release toxic particles related to diseases such as respiratory difficulties, liver or kidney failure or different types of cancer. The World Health Organization (WHO) estimates that 12.6 million deaths a year are related to interaction with unhealthy environments. Although some of these are attributable to outdoor air pollution, the agency warns that there is an "urgent need for investment in strategies to reduce environmental risks in our cities, homes and workplaces."
The choice of materials
A clear example of how materials used in construction can affect health is asbestos. This mineral fibre composite was used for much of the 20th century for its insulating properties and low cost in all types of buildings. But then it was discovered that the decomposition of its fibres resulted in microscopic fragments that, when inhaled, acted as agents directly related to the development of different types of cancer.
For example, they can cause lung cancer or malignant mesothelioma (a cancer found in the lining of the lungs, chest or abdomen), according to the U.S. National Cancer Institute. In recent decades, the use of this material in construction has been banned in most countries, but there are still many buildings in which it remains. In fact, it is estimated that around 125 million people worldwide are at risk of exposure to asbestos.
The exposure of users and workers to the decomposition of asbestos fibres is directly linked to several types of cancer. Image: Wikimedia.
This is not the only material that poses a health hazard to those exposed to it. Some paints, coatings and treatments for various materials may contain volatile agents that are toxic and even carcinogenic if inhaled, such as formaldehyde. Geological materials, such as granite, can give off radon gas, which is radioactive and can accumulate dangerously indoors. Even plastics commonly used in construction, such as PVC, can be a source of phthalates, a plasticising compound that collects in household dust and is linked to the development of respiratory conditions such as asthma.
"The materials we have traditionally used for construction give off chemical components, including those known as volatile organic compounds (VOCs)," explains Nuria Gil, a specialist in bioconstruction and indoor air analysis, "especially the plastic components found in materials and finishes such as paints or varnishes." These chemical components, says Gil, are emitted for six years from their manufacture and have negative consequences on people's health: from respiratory disorders to skin itching or headaches.
To avoid the accumulation of toxic agents, planning and the choice of raw materials and finishes are important: "You have to think carefully about how you are going to build a space, what materials you are going to use and how they are going to affect the users," says Gil. Choosing materials that reduce the emission and accumulation of chemical compounds, as well as bacteria and other agents that can threaten health, is the first step towards achieving healthy spaces. The use of low VOC paints and coatings, the preference for healthier materials such as wood or steel, and the reduction of plastics and petroleum derivatives are some of the decisions that promote the health of users and those who work in the construction of the space.
The importance of ventilation and insulation
The accumulation of some compounds poses a considerable threat considering that humans spend 90% of our time indoors, whether in our homes, at work or in commercial or leisure premises. This is why indoor air quality is a key public health issue and ventilation is one of the most effective measures to achieve it.
Continuous or periodic ventilation of the interior of a space is the best way to ensure air quality. Credit: Kevin Woblick/ Unsplash.
"Proper ventilation is vital when it comes to maintaining healthy indoor spaces, as it is the only tool that ensures that the air is renewed and prevents the accumulation of substances that are harmful to our body," says Javier Perez, architect at COAA. In addition to the pollutants that are released from materials, other substances, such as those found in cleaning products or released in the combustion of stoves or heaters, run the risk of accumulating. Also, some viruses and bacteria proliferate in environments where air circulation is limited or of poor quality or where certain levels of humidity accumulate.
Natural air circulation has traditionally been the most widely used system for the ventilation of spaces, but it is sometimes at odds with the energy efficiency of some places, especially by disrupting the climatization provided by heating or air conditioning systems, which is lost when the space is exposed to the outdoors. In addition, environmental pollution in cities makes natural ventilation the gateway to other contaminates that are outside the space to be ventilated. In recent years, according to Pérez, "mechanical ventilation and temperature and air control systems have become more sophisticated and are now installed in most newly constructed buildings." These systems provide a complete renewal of the air without the need to open doors or windows, thereby maintaining a constant temperature through a heat recuperator.
In this way, constant temperature and humidity standards can be maintained without great energy expenditure. In addition, through detectors that measure the accumulation of particles such as CO2, and filters, the ventilation systems ensure that the indoor air quality is always optimal.
Proper insulation prevents interference from external factors, such as noise, and keeps the temperature constant. Credit: Brett and Sue Coulstock/Flickr.
Proper insulation is therefore the third element to consider for a healthy space. Insulating a space from the outside means protecting it from external agents such as pollution and humidity, helping to maintain a constant temperature that is suitable for our bodies and avoiding external noise. This last factor can be particularly harmful: high exposure to noise pollution, in addition to affecting stress levels or sleep quality, can have a negative influence on blood pressure or cholesterol levels.
In short, paying attention to the selection of materials, planning and choosing the most appropriate ones for each space, implementing correct and constant ventilation and ensuring adequate insulation to protect us from external elements are the keys to the design and construction of healthy spaces that contribute to improving our well-being and quality of life.
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Tungsteno is a journalism laboratory to scan the essence of innovation. Devised by Materia Publicaciones Científicas for Sacyr’s blog.