To certify a LEED project, sustainable design and construction strategies must be incorporated from the earliest stage of the project and must consider the joint participation of all actors, including the owner, architects, engineers, landscapers, builders, etc.[6]​.

LEED certification encourages specialties to implement joint efficiency strategies. This integration, focused on the sustainable design and sustainable development of our green building, allows us to better articulate the goals or objectives set and thus achieve a better level of certification. The certification process is carried out through consulting offices[7]​ that advise the projects, they are not certifiers or reviewers, since the only body empowered to grant LEED certification is the USGBC in the United States. The certification service is carried out completely online, through the USGBC website. For this, the consulting body documents the necessary information and uploads it to the network. This information can be uploaded divided into stages (design and construction), or all the information at once.

Regional credits are another feature of LEED through which the importance of local conditions in determining best environmental construction and design practices is recognized. LEED projects will be able to earn “bonus points” for implementing sustainable building strategies that address important environmental issues facing a specific region. A project may be awarded up to four additional points, each of which will be awarded for achieving up to four of the six priority credits.

1. • Location and Transportation (16 points): Avoid development in inappropriate sites. Reduce vehicle travel distance. Promote livability and improve human health by encouraging daily physical activity.

2. • Sustainable sites (10 points): Mainly advocates defining correct location criteria for projects, the Revitalization of underused or abandoned land, connectivity or proximity to public transportation, the protection or restoration of the habitat and the adequate management and control of rainwater on the selected land.

3. • Efficient Use of Water (10 points): Encourages the use of water resources in the most efficient way, through the reduction of irrigation water, with the appropriate selection of species and the use of low-consumption sanitary devices, for example.

4. • Energy and Atmosphere (35 points): It must comply with the minimum requirements of Standard ASHRAE 90.1-2007 for efficient use of the energy we use in our projects. For this, a percentage of energy savings must be demonstrated (ranging from 12% to 48% or more) compared to a base case that meets the standard. In addition, adequate long-term behavior of the building systems must be ensured in this category.

5. • Materials and Resources (14 points): Describes the parameters that a sustainable building should consider when selecting its materials. In this category, the materials used are regional, recycled, rapidly renewable and/or certified with a green seal, such as an Environmental Product Declaration verified in accordance with the UNE-EN ISO 14025 and UNE-EN 15804 Standards, among other requirements.

6. • Indoor Environmental Quality (15 points): Describes the parameters necessary to provide an adequate indoor environment in buildings, adequate ventilation, thermal and acoustic comfort, control of contaminants in the environment and correct lighting levels for users.

7. • Innovation in Design (6 points): Credits against sustainable building experience, as well as design measures that are not covered under the five LEED credit categories.

8. • Regional Priority (4 points).

Total: 100 basis points; 6 possible in Design Innovation and 4 points in Regional Priority.

Result:.

• - 40 to 49 points: LEED Certified.

• - 50 to 59 points: LEED Silver.

• - 60 to 79 points: LEED Gold (Gold).

• - 80 or more points: LEED Platinum of the six priority credits.

There are various types of LEED certification aimed at the use that a green building can have. Within the project evaluation, it is first defined which certification system is appropriate for that specific project. Among the most important systems we find:[8]​.

1. • LEED NC; LEED for New Construction: It is designed primarily for new commercial office construction, but has been applied by professionals to other types of buildings. All commercial buildings as defined by the building standard are eligible for this certification. We find; office buildings, high-rise residential buildings, government buildings, institutional buildings (museums, churches), leisure facilities, manufacturing plants and laboratories, among others.

2. • LEED EB; LEED for Existing Buildings: This system aims to maximize operational efficiency and minimize a building's environmental impacts. LEED for Existing Buildings addresses the entire building in terms of cleaning and maintenance, recycling programs, exterior maintenance programs, systems and upgrades. It can be applied to both existing buildings seeking LEED certification for the first time and to projects previously certified under LEED for new construction.

3. • LEED for Homes; LEED for Housing: This system promotes high-performance green design and construction for housing. A green house uses less energy, water and natural resources, generates less waste, and is healthier and more comfortable for occupants. The benefits of a LEED certified home include reduced greenhouse gas emissions and reduced exposure to mold, mildew, and other indoor toxins.

4. • LEED ND; LEED for Neighborhood Development: Integrates the principles of smart growth, urbanism and green building into the first national neighborhood design system, which must meet the highest standards of respect for the environment.

5. • LEED SC; LEED for Schools: Integrates the principles of intelligent design that an educational institution should have.

The LEED certification system is based on the analysis and validation by an independent agent, the US Green Building Council (USGBC), of a series of aspects of each project related to sustainability.

There are several evaluation systems depending on the use and complexity of the buildings. Although initially focused on new buildings, other evaluation systems have subsequently been developed for interior conditioning works (LEED for Commercial Interiors) or for buildings in operation (LEED Operations and Maintenance). These standards evolve over time, with a criterion of continuous improvement focused on progressively increasing the degree of demand, in parallel with the improvement of aspects related to sustainability in the building industry. In 2009, the following standards were set:

Green Building Design & Construction.

• - LEED for New Construction and Major Renovations.

• - LEED for Core & Shell Development.

• - LEED for Schools.

• - LEED for Retail New Construction (scheduled for 2010).

Green Interior Design & Construction.

• - LEED for Commercial Interiors.

• - LEED for Retail Interiors (scheduled for 2010).

Green Building Operations & Maintenance.

• - LEED for Existing Buildings: Operations & Maintenance.

Green Neighborhood Development.

• - LEED for Neighborhood Development.

Green Home Design and Construction.

• - LEED for Homes.

In general, the methodology of all LEED evaluation systems is the same. Several categories are established, typically seven: Sustainable Sites, Water Efficiency, Energy and Atmosphere, Materials and Resources, Indoor Environmental Quality, Innovation in Design and Regional Priorities. These chapters include a series of mandatory compliance requirements (Prerequisites) and voluntary compliance credits (credits). The justification of compliance with these parameters grants a series of points, based on which the degree of certification is granted (LEED Certificate, Silver, Gold or Platinum).

The certification process in the most common modalities (new buildings) takes place during the design and construction phases of the building, with certification being obtained at the end of the construction phase. Although there is no requirement to undertake certification, it is common for project agents to incorporate a specialized advisor.

In addition to building certification, the USGBC has training and certification programs for professionals, through the LEED Accredited Professional (LEED AP) and LEED Green Associate (LEED GA) degrees.

Certification is the proof that guarantees the knowledge, skills and abilities required to practice the profession. Its revalidation must be periodic to guarantee the professional's updating and offer high quality services to clients and users.

Although LEED was initially conceived in the United States, it has been used in other parts of the world, with certified buildings currently existing in more than 30 countries. In this sense, the relevance of the use of LEED criteria in various contexts has been discussed, given that the certification refers to American regulations (such as the ASHRAE/IESNA, ANSI or ASTM standards) of complex or unviable applicability in other countries.

The weight of aspects related to the energy efficiency of buildings in LEED certification has also been criticized. In that sense, the different versions have progressively increased the weight of these aspects in the certification.

Buildings currently consume 17% of drinking water and 40% of energy consumption in the world. Sustainable buildings are a consequence of climate change; the green buildings project has been under development for fourteen years. By 2010, the United States had the largest number of LEED buildings in the world, with a total of 5,707 certified buildings out of 27,851 registered buildings. Clearly the United States leads the way in the construction of green buildings but due to the effects of the real estate crisis that the United States has suffered since 2008, the trend has been decreasing. In Latin America, the opposite is true; in recent years the region has been experiencing significant growth in its economies. The development of green buildings in the region occurred thanks to the growth of exports from several countries such as Brazil, Mexico, Uruguay, Chile, Argentina, Colombia and Peru; These exports grew at historic levels and also thanks to the fact that construction did not penetrate the GDP of the aforementioned countries so much.

The top ten countries that in 2010 were in the process of obtaining LEED certification or certified projects:.

1. • Argentina: 48 buildings with LEED certification and 158 in the certification process (2017).[9]​.

2. • Brazil: 43 buildings with LEED certification and 158 in the certification process.

3. • Colombia: As of March 6, 2018 there are 122 certified projects and 229 in process.

4. • El Salvador: First Buildings with LEED Gold Certification, a Building with LEED Platinum Certification, with the highest score in Central America and 25 more to confirm.[10]​.

5. • Costa Rica: 21 in the certification process.

6. • Peru: 16 buildings with LEED certification and 110 in the certification process.

7. • Mexico: 329 buildings with LEED certification and 678 in the certification process.[11]​.

8. • Chile: 6 buildings with LEED certification and 47 in the certification process.

9. • Uruguay: 12 certified buildings and at least 21 projects in the certification process.

10. • British Virgin Islands: 5 buildings in the certification process.

11. • Panama: 3 buildings with LEED certification and 13 in the certification process.

12. • Bolivia: 2 buildings in the certification process: Manzana 40 Building in Santa Cruz de la Sierra and Green Tower Building in La Paz.

Mexico is the country in Latin America that has the largest number of certified green buildings as well as the most buildings in the certification process.

Brazil is the second country with the most green buildings in Latin America, this is because Brazil had to organize the 2014 World Cup and the Rio Olympic Games in 2016. The Olympic Committee ordered that all stadiums that were going to be used in 2016 for the games had to comply with environmental regulations, this led to the construction of green stadiums. For the 2014 World Cup, FIFA does not require its stadiums to comply with environmental regulations. Likewise, 4 of the 12 stadiums that were used for the World Cup already had LEED certification before the event began, the remaining 8 obtained their certification later. All of this made Brazil begin to think more about the construction of green buildings and worry about the environment, such is the case that today they are the leaders in the region in constructions of this type.

Lila Herrera of Econova Institute") supports that in the near future "international sustainability certificates such as the Living Building Challenge will begin to be implemented, and some developers will seek to make office buildings, hotels, and other buildings for public use, seeking the maximum in sustainability and, new themes such as regenerative architecture and biophilia will become increasingly important."[12]

Currently, in Spain, there is a single representative body for LEED issues in Spain, and a direct interlocutor with the USGBC (the body that creates, verifies and develops the LEED tool in the world); This organization is GBCe: GBC Spain, which also works in parallel in collaboration with the USGBC (Green Building Council of the United States, and other GBCs around the world) to help develop and implement the tool, adapting it to the demands, requirements and regulations in each country.

Currently in Spain there is another controversy, since there is a company, Spain GBC, that claims to be an official body, which is not the case; sometimes creating confusion due to the name it has. On May 26, 2013, this company, the Spain Green Building Council, issued a press release in support of hydraulic fracturing, which motivated various entities that support ecological architecture and environmental NGOs to issue a statement of disagreement.[13]​.

• - Environment.

• - Bioconstruction.

• - Sustainable architecture.

• - Environmental product declaration.

• - Renewable energy.

• - Energy efficiency.

• - Palmas Altas Technology Center: LEED platinum building.[14]​.

• - USGBC website.

To certify a LEED project, sustainable design and construction strategies must be incorporated from the earliest stage of the project and must consider the joint participation of all actors, including the owner, architects, engineers, landscapers, builders, etc.[6]​.

LEED certification encourages specialties to implement joint efficiency strategies. This integration, focused on the sustainable design and sustainable development of our green building, allows us to better articulate the goals or objectives set and thus achieve a better level of certification. The certification process is carried out through consulting offices[7]​ that advise the projects, they are not certifiers or reviewers, since the only body empowered to grant LEED certification is the USGBC in the United States. The certification service is carried out completely online, through the USGBC website. For this, the consulting body documents the necessary information and uploads it to the network. This information can be uploaded divided into stages (design and construction), or all the information at once.

Regional credits are another feature of LEED through which the importance of local conditions in determining best environmental construction and design practices is recognized. LEED projects will be able to earn “bonus points” for implementing sustainable building strategies that address important environmental issues facing a specific region. A project may be awarded up to four additional points, each of which will be awarded for achieving up to four of the six priority credits.

1. • Location and Transportation (16 points): Avoid development in inappropriate sites. Reduce vehicle travel distance. Promote livability and improve human health by encouraging daily physical activity.

2. • Sustainable sites (10 points): Mainly advocates defining correct location criteria for projects, the Revitalization of underused or abandoned land, connectivity or proximity to public transportation, the protection or restoration of the habitat and the adequate management and control of rainwater on the selected land.

3. • Efficient Use of Water (10 points): Encourages the use of water resources in the most efficient way, through the reduction of irrigation water, with the appropriate selection of species and the use of low-consumption sanitary devices, for example.

4. • Energy and Atmosphere (35 points): It must comply with the minimum requirements of Standard ASHRAE 90.1-2007 for efficient use of the energy we use in our projects. For this, a percentage of energy savings must be demonstrated (ranging from 12% to 48% or more) compared to a base case that meets the standard. In addition, adequate long-term behavior of the building systems must be ensured in this category.

5. • Materials and Resources (14 points): Describes the parameters that a sustainable building should consider when selecting its materials. In this category, the materials used are regional, recycled, rapidly renewable and/or certified with a green seal, such as an Environmental Product Declaration verified in accordance with the UNE-EN ISO 14025 and UNE-EN 15804 Standards, among other requirements.

6. • Indoor Environmental Quality (15 points): Describes the parameters necessary to provide an adequate indoor environment in buildings, adequate ventilation, thermal and acoustic comfort, control of contaminants in the environment and correct lighting levels for users.

7. • Innovation in Design (6 points): Credits against sustainable building experience, as well as design measures that are not covered under the five LEED credit categories.

8. • Regional Priority (4 points).

Total: 100 basis points; 6 possible in Design Innovation and 4 points in Regional Priority.

Result:.

• - 40 to 49 points: LEED Certified.

• - 50 to 59 points: LEED Silver.

• - 60 to 79 points: LEED Gold (Gold).

• - 80 or more points: LEED Platinum of the six priority credits.

There are various types of LEED certification aimed at the use that a green building can have. Within the project evaluation, it is first defined which certification system is appropriate for that specific project. Among the most important systems we find:[8]​.

1. • LEED NC; LEED for New Construction: It is designed primarily for new commercial office construction, but has been applied by professionals to other types of buildings. All commercial buildings as defined by the building standard are eligible for this certification. We find; office buildings, high-rise residential buildings, government buildings, institutional buildings (museums, churches), leisure facilities, manufacturing plants and laboratories, among others.

2. • LEED EB; LEED for Existing Buildings: This system aims to maximize operational efficiency and minimize a building's environmental impacts. LEED for Existing Buildings addresses the entire building in terms of cleaning and maintenance, recycling programs, exterior maintenance programs, systems and upgrades. It can be applied to both existing buildings seeking LEED certification for the first time and to projects previously certified under LEED for new construction.

3. • LEED for Homes; LEED for Housing: This system promotes high-performance green design and construction for housing. A green house uses less energy, water and natural resources, generates less waste, and is healthier and more comfortable for occupants. The benefits of a LEED certified home include reduced greenhouse gas emissions and reduced exposure to mold, mildew, and other indoor toxins.

4. • LEED ND; LEED for Neighborhood Development: Integrates the principles of smart growth, urbanism and green building into the first national neighborhood design system, which must meet the highest standards of respect for the environment.

5. • LEED SC; LEED for Schools: Integrates the principles of intelligent design that an educational institution should have.

The LEED certification system is based on the analysis and validation by an independent agent, the US Green Building Council (USGBC), of a series of aspects of each project related to sustainability.

There are several evaluation systems depending on the use and complexity of the buildings. Although initially focused on new buildings, other evaluation systems have subsequently been developed for interior conditioning works (LEED for Commercial Interiors) or for buildings in operation (LEED Operations and Maintenance). These standards evolve over time, with a criterion of continuous improvement focused on progressively increasing the degree of demand, in parallel with the improvement of aspects related to sustainability in the building industry. In 2009, the following standards were set:

Green Building Design & Construction.

• - LEED for New Construction and Major Renovations.

• - LEED for Core & Shell Development.

• - LEED for Schools.

• - LEED for Retail New Construction (scheduled for 2010).

Green Interior Design & Construction.

• - LEED for Commercial Interiors.

• - LEED for Retail Interiors (scheduled for 2010).

Green Building Operations & Maintenance.

• - LEED for Existing Buildings: Operations & Maintenance.

Green Neighborhood Development.

• - LEED for Neighborhood Development.

Green Home Design and Construction.

• - LEED for Homes.

In general, the methodology of all LEED evaluation systems is the same. Several categories are established, typically seven: Sustainable Sites, Water Efficiency, Energy and Atmosphere, Materials and Resources, Indoor Environmental Quality, Innovation in Design and Regional Priorities. These chapters include a series of mandatory compliance requirements (Prerequisites) and voluntary compliance credits (credits). The justification of compliance with these parameters grants a series of points, based on which the degree of certification is granted (LEED Certificate, Silver, Gold or Platinum).

The certification process in the most common modalities (new buildings) takes place during the design and construction phases of the building, with certification being obtained at the end of the construction phase. Although there is no requirement to undertake certification, it is common for project agents to incorporate a specialized advisor.

In addition to building certification, the USGBC has training and certification programs for professionals, through the LEED Accredited Professional (LEED AP) and LEED Green Associate (LEED GA) degrees.

Certification is the proof that guarantees the knowledge, skills and abilities required to practice the profession. Its revalidation must be periodic to guarantee the professional's updating and offer high quality services to clients and users.

Although LEED was initially conceived in the United States, it has been used in other parts of the world, with certified buildings currently existing in more than 30 countries. In this sense, the relevance of the use of LEED criteria in various contexts has been discussed, given that the certification refers to American regulations (such as the ASHRAE/IESNA, ANSI or ASTM standards) of complex or unviable applicability in other countries.

The weight of aspects related to the energy efficiency of buildings in LEED certification has also been criticized. In that sense, the different versions have progressively increased the weight of these aspects in the certification.

Buildings currently consume 17% of drinking water and 40% of energy consumption in the world. Sustainable buildings are a consequence of climate change; the green buildings project has been under development for fourteen years. By 2010, the United States had the largest number of LEED buildings in the world, with a total of 5,707 certified buildings out of 27,851 registered buildings. Clearly the United States leads the way in the construction of green buildings but due to the effects of the real estate crisis that the United States has suffered since 2008, the trend has been decreasing. In Latin America, the opposite is true; in recent years the region has been experiencing significant growth in its economies. The development of green buildings in the region occurred thanks to the growth of exports from several countries such as Brazil, Mexico, Uruguay, Chile, Argentina, Colombia and Peru; These exports grew at historic levels and also thanks to the fact that construction did not penetrate the GDP of the aforementioned countries so much.

The top ten countries that in 2010 were in the process of obtaining LEED certification or certified projects:.

1. • Argentina: 48 buildings with LEED certification and 158 in the certification process (2017).[9]​.

2. • Brazil: 43 buildings with LEED certification and 158 in the certification process.

3. • Colombia: As of March 6, 2018 there are 122 certified projects and 229 in process.

4. • El Salvador: First Buildings with LEED Gold Certification, a Building with LEED Platinum Certification, with the highest score in Central America and 25 more to confirm.[10]​.

5. • Costa Rica: 21 in the certification process.

6. • Peru: 16 buildings with LEED certification and 110 in the certification process.

7. • Mexico: 329 buildings with LEED certification and 678 in the certification process.[11]​.

8. • Chile: 6 buildings with LEED certification and 47 in the certification process.

9. • Uruguay: 12 certified buildings and at least 21 projects in the certification process.

10. • British Virgin Islands: 5 buildings in the certification process.

11. • Panama: 3 buildings with LEED certification and 13 in the certification process.

12. • Bolivia: 2 buildings in the certification process: Manzana 40 Building in Santa Cruz de la Sierra and Green Tower Building in La Paz.

Mexico is the country in Latin America that has the largest number of certified green buildings as well as the most buildings in the certification process.

Brazil is the second country with the most green buildings in Latin America, this is because Brazil had to organize the 2014 World Cup and the Rio Olympic Games in 2016. The Olympic Committee ordered that all stadiums that were going to be used in 2016 for the games had to comply with environmental regulations, this led to the construction of green stadiums. For the 2014 World Cup, FIFA does not require its stadiums to comply with environmental regulations. Likewise, 4 of the 12 stadiums that were used for the World Cup already had LEED certification before the event began, the remaining 8 obtained their certification later. All of this made Brazil begin to think more about the construction of green buildings and worry about the environment, such is the case that today they are the leaders in the region in constructions of this type.

Lila Herrera of Econova Institute") supports that in the near future "international sustainability certificates such as the Living Building Challenge will begin to be implemented, and some developers will seek to make office buildings, hotels, and other buildings for public use, seeking the maximum in sustainability and, new themes such as regenerative architecture and biophilia will become increasingly important."[12]

Currently, in Spain, there is a single representative body for LEED issues in Spain, and a direct interlocutor with the USGBC (the body that creates, verifies and develops the LEED tool in the world); This organization is GBCe: GBC Spain, which also works in parallel in collaboration with the USGBC (Green Building Council of the United States, and other GBCs around the world) to help develop and implement the tool, adapting it to the demands, requirements and regulations in each country.

Currently in Spain there is another controversy, since there is a company, Spain GBC, that claims to be an official body, which is not the case; sometimes creating confusion due to the name it has. On May 26, 2013, this company, the Spain Green Building Council, issued a press release in support of hydraulic fracturing, which motivated various entities that support ecological architecture and environmental NGOs to issue a statement of disagreement.[13]​.

• - Environment.

• - Bioconstruction.

• - Sustainable architecture.

• - Environmental product declaration.

• - Renewable energy.

• - Energy efficiency.

• - Palmas Altas Technology Center: LEED platinum building.[14]​.

• - USGBC website.