Sometimes it is thought that to build sustainably, complex analysis and project studies must be carried out, and complicated technologies and advanced systems must be integrated that allow us to achieve considerable energy savings, but this is not always the case. It is not said that the implementation of technologies to make constructions more efficient is wrong, what is clear is that these elements cannot be abused to resolve design situations that could be easily resolved from the very origin of the project. Taking a moment to analyze the challenge that a new project represents, understanding how this possible construction relates to its immediate context, to its climate, to its orientation, to its topography, to the whole, is what will allow us to make the decisions that will make architecture more efficient.

Good design practices, in addition to making architecture and construction more efficient, make them less expensive in terms of their energy consumption, which is reflected in operating costs and also reduces the impact of their carbon footprint on the world. These practices are outside, for thousands of years human beings have applied them, just look at the vernacular architecture, we have built efficient spaces for centuries, cool houses in the desert, on the coast, without the need for air conditioning. Carrying out good design practices is no more costly than taking a moment to analyze the problem.[3]​.

Construction with straw:.

According to Roger L. Welsch, Nebraska state historian and researcher on the origins of straw buildings, it was between 1886 and 1887 when the first straw module was built, near Bayard, Nebraska, United States. It was used as a school room or hall. The use of this technique spread between 1915 and 1930; Its practice was abandoned at the end of the 1940s and resumed in the 1970s. Building houses with straw bales is a simple system that can be learned in a few days and in which everyone can participate. Less specialized labor and less construction time are required than traditional methods, such as concrete. By using straw bales, probably the most ecological thing that can be used in a home for construction, the amount of agricultural waste that is burned is reduced, minimizing air pollution and global warming.

Bales have a greater thermal insulation capacity than wood, bricks and even adobe. This feature is ideal for areas with extreme climates, as it reduces the energy expenditure required to cool and heat a building.

Thermal efficiency is measured by the “R” value of resistance to heat flow. The resistance to heat flow of the straw bales is equal to 42.8. It is preferable to use wheat or oat straw, but seedless sorghum straw can also be used. The bales must only be “straw” bales, which are obtained after harvesting the seed.[4]​.

Bamboo construction:.

Bamboo is a woody grass that renews itself naturally every seven years and does not require the use of pesticides or fertilizers if it is grown properly. Depending on the species, it can grow between 7.5 and 40 cm per day and reach 40 m in three or four months.

Pillars, roofs, ceilings, walls or coatings are applied. If it is used for the structure, its maximum resistance is needed (the darker the bamboo, the softer it is) and elasticity. In Latin America and Asia, the cane "Cane (vegetable)") is used, intertwined through knot structures. For coverings it can be presented in the form of panels.[2]​.

Adobe construction:.

Adobe is made up of a mass of mud (clay, sand and water) sometimes mixed with straw, coconut fiber or even manure, molded into a brick and dried in the sun for 25-30 days. The main mixture is 20% clay and 80% sand and water. Its embodied energy is 0.4 MJ/KG. The more embodied energy a construction material has, the more energy has been expended during its production.

Adobe is a good acoustic insulator and has great thermal inertia, which is why it serves as a regulator of internal temperature: in summer it preserves coolness and during winter, heat. If well executed and maintained, an adobe building can last a hundred years or more.

Some alternatives for adobe can be Tapia and Cannabric.[2]​.

Pet Blocks:.

It arises from the success of modules and projects for green roofs, from there recycled plastic blocks (high-density polyethylene) were materialized for the construction of new housing or even for remodeling. The advantages it presents are savings in material waste, construction time is speeded up, savings are made in foundations, the use of steel and 70% of concrete and mortar are reduced by up to 60%, in addition to being an excellent acoustic and thermal insulator and it is very functional in dividing and load-bearing walls since it supports up to 750kg/m with spans of up to 6m and with constructions of up to three floors.

Thanks to its flexibility and resistance, in the event of an earthquake, it demonstrates an excellent response, unlike other materials, in addition to the fact that in construction costs it enables savings of up to 40%. Due to all these characteristics, it is very well used in industrial plants, self-service stores and of course homes.[5]​.

*Pet sheets:**.

To manufacture them, polyethylene and polypropylene are used, which are obtained from plastic bags and wrappers that are collected in the area's ravines, as well as from discarded packaging material. After grinding both materials, they undergo a pre-casting process, at 250 degrees Celsius, the color is integrated, it is passed to a calendering system, where the thickness is given to the material and it immediately falls into a casting mold. The raw material is transformed into plastic roofing sheets with a maintenance-free life of 20 years.

These sheets are recognized for their ecological profile, since waste plastics are recycled and do not pollute, in addition to the fact that the plastic is not melted, but rather softened and molded. Among their characteristics, their useful life stands out, they are thermal, they are practically unbreakable, easy to handle, they are not noisy in the rain, etc.[6]​.

These types of ecological brick do not contaminate the environment with CO, which increases pollution, as does the common partition brick, since using this manufacturing technique does not depend on the partition for firing but directly uses sunlight for drying and ready for construction.

It is very economically profitable since its investment requires less than half of what it would cost to invest in a common brick made of clay.

Some advantages of ecological brick depending on the material with which it is built, some will be more enhanced than others. But in general its advantages are: Less damage to nature, since its manufacturing requires less energy and waste as well as the recycling of other waste materials. They are better insulators from the cold and heat outside, meaning less energy is spent in the home. In some cases they are cheaper than conventional ones, but when this is not the case, as they are better insulators, the energy savings offset the difference. The materials of ecological bricks make them lighter and more manageable for the worker, speeding up construction time and reducing expenses.

The disadvantage of ecological bricks is that they are beginning to enter the market and in some areas they are not yet available and you have to order them. They also have another disadvantage derived from the newness of this product and that is that, at the moment, there are no decorative varieties like the conventional ones to decorate facades, walls, gardens, etc.

For the compacted eco-brick, you need 2L recycled bottles and a funnel to fill the bottle; such as materials, sand, mud or gravel and a rod to push the material used when filling the bottles and remove all the oxygen so that there are no air bubbles. It is filled in proportion, first up to half, then three quarters and finally until it is completely filled and closed tightly. This results in a cylindrical compacted brick ready to build.

As already mentioned, the use of recycled materials or materials taken directly from the trash has also been implemented in the construction process. A team at the Andrés Bello University, Venezuela, together with the company Golden Concret, is working to transform household waste (food, plastics, papers, etc.) into panels, bricks and other construction materials. These are designed so that they do not transmit infections nor have an unpleasant odor.[7]​.

Architect Michael Reynolds has also dedicated himself to the construction of what he calls “earthships” which are bunker-style houses made of natural and recycled materials and which in the end are sustainable houses.[8]​.

concrete block

Its main characteristic is that it is made of cellular concrete, which results in lifelong energy savings and reduces heating costs in winter and maintains a cool environment in summer. Within the structure of the concrete block we can find the following benefits:[9]​.

Sustainable concrete with rice ashes

So far this material is under investigation in the hands of Franco Zunino, a student of Construction Engineering and Management at UC, together with professor Mauricio López. The intention is to manufacture more sustainable concrete by replacing cement with rice husk ash.

The objective of the research is to determine the effects on strength and durability of the partial replacement of cement with rice husk ash in concrete mixtures. Among the results, it is possible to replace up to 20% of pure cement in a mixture without affecting its resistance, while producing a durable concrete with a lower final emission of greenhouse gases.[10]​.

Sometimes it is thought that to build sustainably, complex analysis and project studies must be carried out, and complicated technologies and advanced systems must be integrated that allow us to achieve considerable energy savings, but this is not always the case. It is not said that the implementation of technologies to make constructions more efficient is wrong, what is clear is that these elements cannot be abused to resolve design situations that could be easily resolved from the very origin of the project. Taking a moment to analyze the challenge that a new project represents, understanding how this possible construction relates to its immediate context, to its climate, to its orientation, to its topography, to the whole, is what will allow us to make the decisions that will make architecture more efficient.

Good design practices, in addition to making architecture and construction more efficient, make them less expensive in terms of their energy consumption, which is reflected in operating costs and also reduces the impact of their carbon footprint on the world. These practices are outside, for thousands of years human beings have applied them, just look at the vernacular architecture, we have built efficient spaces for centuries, cool houses in the desert, on the coast, without the need for air conditioning. Carrying out good design practices is no more costly than taking a moment to analyze the problem.[3]​.

Construction with straw:.

According to Roger L. Welsch, Nebraska state historian and researcher on the origins of straw buildings, it was between 1886 and 1887 when the first straw module was built, near Bayard, Nebraska, United States. It was used as a school room or hall. The use of this technique spread between 1915 and 1930; Its practice was abandoned at the end of the 1940s and resumed in the 1970s. Building houses with straw bales is a simple system that can be learned in a few days and in which everyone can participate. Less specialized labor and less construction time are required than traditional methods, such as concrete. By using straw bales, probably the most ecological thing that can be used in a home for construction, the amount of agricultural waste that is burned is reduced, minimizing air pollution and global warming.

Bales have a greater thermal insulation capacity than wood, bricks and even adobe. This feature is ideal for areas with extreme climates, as it reduces the energy expenditure required to cool and heat a building.

Thermal efficiency is measured by the “R” value of resistance to heat flow. The resistance to heat flow of the straw bales is equal to 42.8. It is preferable to use wheat or oat straw, but seedless sorghum straw can also be used. The bales must only be “straw” bales, which are obtained after harvesting the seed.[4]​.

Bamboo construction:.

Bamboo is a woody grass that renews itself naturally every seven years and does not require the use of pesticides or fertilizers if it is grown properly. Depending on the species, it can grow between 7.5 and 40 cm per day and reach 40 m in three or four months.

Pillars, roofs, ceilings, walls or coatings are applied. If it is used for the structure, its maximum resistance is needed (the darker the bamboo, the softer it is) and elasticity. In Latin America and Asia, the cane "Cane (vegetable)") is used, intertwined through knot structures. For coverings it can be presented in the form of panels.[2]​.

Adobe construction:.

Adobe is made up of a mass of mud (clay, sand and water) sometimes mixed with straw, coconut fiber or even manure, molded into a brick and dried in the sun for 25-30 days. The main mixture is 20% clay and 80% sand and water. Its embodied energy is 0.4 MJ/KG. The more embodied energy a construction material has, the more energy has been expended during its production.

Adobe is a good acoustic insulator and has great thermal inertia, which is why it serves as a regulator of internal temperature: in summer it preserves coolness and during winter, heat. If well executed and maintained, an adobe building can last a hundred years or more.

Some alternatives for adobe can be Tapia and Cannabric.[2]​.

Pet Blocks:.

It arises from the success of modules and projects for green roofs, from there recycled plastic blocks (high-density polyethylene) were materialized for the construction of new housing or even for remodeling. The advantages it presents are savings in material waste, construction time is speeded up, savings are made in foundations, the use of steel and 70% of concrete and mortar are reduced by up to 60%, in addition to being an excellent acoustic and thermal insulator and it is very functional in dividing and load-bearing walls since it supports up to 750kg/m with spans of up to 6m and with constructions of up to three floors.

Thanks to its flexibility and resistance, in the event of an earthquake, it demonstrates an excellent response, unlike other materials, in addition to the fact that in construction costs it enables savings of up to 40%. Due to all these characteristics, it is very well used in industrial plants, self-service stores and of course homes.[5]​.

*Pet sheets:**.

To manufacture them, polyethylene and polypropylene are used, which are obtained from plastic bags and wrappers that are collected in the area's ravines, as well as from discarded packaging material. After grinding both materials, they undergo a pre-casting process, at 250 degrees Celsius, the color is integrated, it is passed to a calendering system, where the thickness is given to the material and it immediately falls into a casting mold. The raw material is transformed into plastic roofing sheets with a maintenance-free life of 20 years.

These sheets are recognized for their ecological profile, since waste plastics are recycled and do not pollute, in addition to the fact that the plastic is not melted, but rather softened and molded. Among their characteristics, their useful life stands out, they are thermal, they are practically unbreakable, easy to handle, they are not noisy in the rain, etc.[6]​.

These types of ecological brick do not contaminate the environment with CO, which increases pollution, as does the common partition brick, since using this manufacturing technique does not depend on the partition for firing but directly uses sunlight for drying and ready for construction.

It is very economically profitable since its investment requires less than half of what it would cost to invest in a common brick made of clay.

Some advantages of ecological brick depending on the material with which it is built, some will be more enhanced than others. But in general its advantages are: Less damage to nature, since its manufacturing requires less energy and waste as well as the recycling of other waste materials. They are better insulators from the cold and heat outside, meaning less energy is spent in the home. In some cases they are cheaper than conventional ones, but when this is not the case, as they are better insulators, the energy savings offset the difference. The materials of ecological bricks make them lighter and more manageable for the worker, speeding up construction time and reducing expenses.

The disadvantage of ecological bricks is that they are beginning to enter the market and in some areas they are not yet available and you have to order them. They also have another disadvantage derived from the newness of this product and that is that, at the moment, there are no decorative varieties like the conventional ones to decorate facades, walls, gardens, etc.

For the compacted eco-brick, you need 2L recycled bottles and a funnel to fill the bottle; such as materials, sand, mud or gravel and a rod to push the material used when filling the bottles and remove all the oxygen so that there are no air bubbles. It is filled in proportion, first up to half, then three quarters and finally until it is completely filled and closed tightly. This results in a cylindrical compacted brick ready to build.

As already mentioned, the use of recycled materials or materials taken directly from the trash has also been implemented in the construction process. A team at the Andrés Bello University, Venezuela, together with the company Golden Concret, is working to transform household waste (food, plastics, papers, etc.) into panels, bricks and other construction materials. These are designed so that they do not transmit infections nor have an unpleasant odor.[7]​.

Architect Michael Reynolds has also dedicated himself to the construction of what he calls “earthships” which are bunker-style houses made of natural and recycled materials and which in the end are sustainable houses.[8]​.

concrete block

Its main characteristic is that it is made of cellular concrete, which results in lifelong energy savings and reduces heating costs in winter and maintains a cool environment in summer. Within the structure of the concrete block we can find the following benefits:[9]​.

Sustainable concrete with rice ashes

So far this material is under investigation in the hands of Franco Zunino, a student of Construction Engineering and Management at UC, together with professor Mauricio López. The intention is to manufacture more sustainable concrete by replacing cement with rice husk ash.

The objective of the research is to determine the effects on strength and durability of the partial replacement of cement with rice husk ash in concrete mixtures. Among the results, it is possible to replace up to 20% of pure cement in a mixture without affecting its resistance, while producing a durable concrete with a lower final emission of greenhouse gases.[10]​.