Hundreds of millions of homes that the homeless need can be built from environmentally friendly materials: this is a unique chance to meet demand with the help of “green” technologies, GGGI analysts believe
According to the World Bank, by 2030, 300 million houses need to be built to provide a roof over the head of all the inhabitants of the Earth. Most of it is in the world’s poorest countries, where about 1 billion people are considered homeless or have poor living conditions.
According to analysts from the Global Green Growth Institute (GGGI, Seoul-headquartered international organization for the promotion of a green economy), this situation presents a unique opportunity. There is a clear demand for housing, and it can be met inexpensively, efficiently, and environmentally responsibly, they write in the study How to Respond to Global Housing Demand with Low-Carbon Materials.
To do this, we must first of all pay attention to building materials alternative to cement and steel. On the one hand, this will not allow prices for these goods to jump up (following demand), on the other hand, it will save nature from unnecessary emissions of carbon dioxide, which is associated with the production of these materials.
What should houses be built from?
Of course, the recommendations of GGGI specialists are less relevant to our country: due to climatic features and because most of the required housing should be built in Asia and Africa, where it is quite warm and where there is no such developed steel and cement industry. The authors of the study compiled a list of the most obvious “green” materials that can be used to solve this problem, emphasizing that this list is far from complete and serves only as a demonstration of the possibilities. A universally ideal “green” building material, they write, does not yet exist in nature.
1. Plant materials
Instead of being burned or sent to a silo, agricultural waste can be used as building material. Types of plants and processing methods in different regions are different, but the principle can be the same – the creation of panel blocks from plants for construction. Technologies for such processing already exist. The authors of the report include straw, logs, rice fibers, bamboo, hemp (hemp) and even coconut palm fibers to plant materials. Some of them are so widespread that GGGI experts separate them into separate sub-items.
2. Tree
The most obvious “green” building material that has been used by many societies around the world for thousands of years. Innovations in the manufacturing industry in recent years make it possible to create even multi-storey buildings from wood. Of course, the excessive use of wood in construction is directly related to deforestation – one of the key environmental problems of our time, so GGGI analysts call for the use of wood as carefully as possible – definitely not for the construction of a skyscraper complex.
3. Bamboo
A regionally specific material, bamboo has historically been used in homes in South America and East Asia. When processed correctly, it has a fairly high tensile strength and durability, while it is quite light. There is also scientific evidence that bamboo is a good substitute for steel in reinforced concrete, but these discoveries still need to be confirmed in practice.
4. Straw
Straw has also been used in construction for centuries (if not millennia), and there is quite a lot of it in different parts of the world. Modern technologies allow it to be pressed into briquettes, similar to building panels. True, the insulating and heat-resistant properties of straw are directly proportional to the thickness of this layer, which can result in excessively thick walls near houses built from such briquettes.
5. Land
About half of the population in the poorest countries of the world live in earthen houses, and if earlier they were dugouts (dwellings buried in the ground), now we are talking about buildings built on improvised material. By the way, this method of building residential buildings reduces logistics costs and reduces gas emissions from trucks. True, for the most part now these are houses, to put it mildly, of mediocre quality, so one of the priorities is to standardize and increase the efficiency of construction processes.
6. Stone
One of the most popular building materials in the history of mankind is not only durable, it is also environmentally neutral. If there are quarries in the region, this facilitates the process and simplifies the logistics. The authors of the study note: it is important to ensure the repeated use of the stone (if necessary), this should be the task of the designers.
7. Recyclable
Photos of houses lined with bottle caps regularly appear in the press, but here we are talking about the use of recycled materials, even the same steel. For example, iron doors or window frames can be smelted into some new building product and sold to low-cost housing developers. Such a system is in use in Turkey and allows you to save up to 40% on the construction of houses. This approach is fully consistent with the principles of the so-called circular economy.
8. “Green” concrete
Multifunctionality, durability, low cost, fire resistance – concrete has many qualities, which made it one of the most common building materials. That’s just the cement industry is one of the major polluters of nature. GGGI analysts offer two ways to “green” concrete production:
- use more environmentally friendly or recycled substitutes for pozzolan (volcanic tuff), such as blast furnace slag or rice husk ash;
- reuse materials from destroyed buildings.