Are we aware of the global impact on the environment and on people’s health as a result of the use of materials in construction? Advances in technology have enabled the evolution of the technical and construction characteristics of the materials used in the building industry. This evolution has made it possible to modify the raw materials –earth, wood, clay, natural fibers and so on– used in building, and new materials have also appeared. New and better targets have been achieved, but at a high cost: a negative environmental impact, toxicity, lack of transpiration. What is the best way to solve these problems?
The impact of the materials used in the building industry
Building materials have an impact on the environment in all its phases: extraction, transport, processing, deployment, operation, and end of life and disposal. This impact affects the environment and people’s health –‘professional pathologies and diseases’– , and varies according to the characteristics of these materials and the way in which they are transformed, used and discarded. The characteristics of the materials –which determine their impact in all their different phases– are known as their vital or biotic qualities.
There are raw materials existing in nature that have been used for time immemorial to make buildings, such as clay, stone, lime and wood, among others. Place and climate have also been other determining factors in the choice of each material and the most suitable building techniques. However, with the passage of time, these materials have gradually been transformed in order to improve their technical and building performance -‘cement, iron, aluminum, industrial sub-products, synthetic materials and chemical products are among the most important’-, and as a result their physical and chemical characteristics and molecular structure have also been modified. In addition, new substances have also been used that do not occur naturally in nature.
In the case of the construction industry, advances in technology have brought improvements in the technical characteristics of the material, but ‘at the cost of their biological qualities and their environmental harmlessness‘ (Bioconstruction guide, Mandala Ediciones). The emergence of new materials has also brought new problems, such as environmental costs, high radioactivity, toxicity, lack of transpiration, and interference in natural magnetic and electrical fields, among others. All this has led to an environmentally-unfriendly type of construction which is unhealthy and not at all comfortable.
How can we deal with this situation and solve these problems?
Of course, it is not a question of returning to the past, but rather of ceasing to repeat the same mistakes, through careful consideration guided by a different set of priorities:
- Impact on the environment throughout the life cycle.
- Effect on people’s health.
- Energy balance throughout the life cycle.
- Social benefits.
The ‘Bioconstruction Guide’ (1999) gives us an idea of some of these strategies: watch out for the provenance of the raw ingredients in ceramic materials and their firing temperature and avoid temperatures of over 950ºC; restrict the use of cement to the minimum; use lime or plaster mortars rather than cement; make mortars with the sand and gravel available on the terrain; study the impact of using synthetic materials, plastics derived from chlorine chemistry, and so on.
Innovation, development and research is the response, always based on these premises. R+D+I is the best way to achieve the goal of using materials with a positive impact, reducing energy consumption, not over-exploiting resources or producing toxic or unhealthy materials, recycling, reducing waste generation, reutilization and much more. Circular economy.
The Bala-box project consists of building a prototype of a small housing unit using prefabricated wood and straw blocks. The sponsors of this project are Alfonso Zavala, architect, and the other members of the team are Luis Velasco, a carpenter and builder with an interest in bioconstruction techniques; Paloma Folache, restorer and technician in wall applications and expert in natural finishes; and Pablo Bernaola, bioconstructor specializing in thermal inertia heaters.
The aim of this project is to raise awareness of the benefits of ecological, healthy and efficient construction.
Click here to see the original (Spanish version only) publication at i-ambiente.
‘Bioconstruction Guide to healthy building materials and techniques with a low environmental impact‘, by Camilo Rodríguez Lledó and Architecture Team adapted to the environment.