Green building, also called green construction, sustainable building, or eco-friendly building, is a method of creating structures and using processes that protect the environment and save resources throughout a building's life. This includes planning, designing, building, operating, maintaining, repairing, and tearing down a building. It requires teamwork between contractors, architects, engineers, and the building owner at every stage. Green building adds to traditional goals like cost-effectiveness, usefulness, durability, and comfort. It focuses on saving resources like energy, land, water, and materials during the building's life. It also helps protect the environment, reduces pollution, creates healthy and comfortable spaces, and works with nature. Green building uses technology that uses less and produces more, while being cost-effective, environmentally friendly, and efficient.

Leadership in Energy and Environmental Design (LEED) is a system that rates how green buildings are designed, built, and managed. It was created by the U.S. Green Building Council. The Green Building Initiative (GBI) is an organization that creates standards for green buildings and offers certifications like Green Globes. Other systems include BREEAM from the UK, which evaluates buildings and large projects, and the DGNB System in Germany, which checks how sustainable buildings and areas are. The World Green Building Council is studying how green buildings affect people's health and productivity. It works with the World Bank to help countries build greener buildings through programs like EDGE. Other systems include NABERS and Green Star in Australia, GSAS in the Middle East, and GBI in Malaysia.

Building information modeling (BIM) is a method that uses digital models to plan and manage building projects. These models are files that can be shared or used online to help make decisions about buildings and other structures. BIM is used by people, companies, and governments to plan, build, and manage things like water systems, roads, bridges, and tunnels.

New technologies are being created to help build greener structures. The main goal of green buildings is to reduce harm to people's health and the environment. Natural building is a similar idea but often uses local, natural materials and is smaller in scale. Related topics include sustainable design and green architecture. Sustainability means meeting the needs of today without harming the ability of future generations to meet their needs. Some green building programs do not focus on fixing old buildings, but others do, especially through government programs that improve energy efficiency. Green building methods can be used for both new buildings and older ones.

A 2009 report by the U.S. General Services Administration showed that 12 buildings designed with sustainability had lower operating costs and better energy use. People who worked in these buildings were also more satisfied than those in regular buildings. These are examples of eco-friendly buildings.

Reducing environmental impact

Buildings use a lot of energy, electricity, water, and materials. In 2020, they used 37% of the world's energy and caused 33% of global carbon dioxide emissions linked to energy use, according to the United Nations. When including the production of building materials, these emissions reached 39%. If new construction technologies are not used during this time of fast growth, emissions could double by 2050, as reported by the United Nations Environment Program.

Glass buildings, especially all-glass skyscrapers, use a lot of energy because they are not efficient. These buildings look nice and let in natural light, but they trap heat, which increases the need for air conditioning. This leads to more carbon emissions. Experts suggest changing building designs or limiting all-glass buildings to reduce their harmful effects on the environment.

Buildings take up a lot of land. In the United States, about 107 million acres (430,000 km²) are developed, according to the National Resources Inventory. The International Energy Agency estimates that existing buildings use over 40% of the world's total energy and produce 24% of global carbon dioxide emissions.

A 2016 report stated that buildings use more than 30% of all energy produced. It also said that if steps are taken to improve building energy efficiency, the energy used by buildings could stay near current levels by 2050. This would reduce the average energy use of buildings worldwide by more than 80%.

Green building methods aim to reduce the environmental impact of buildings, as the building sector has the best chance to cut emissions with little or no cost. Key guidelines include: making buildings as small as possible, avoiding sprawl even with energy-efficient designs, and using bioclimatic design. Bioclimatic design uses local climate conditions to create comfortable indoor spaces while saving energy. This might involve changing a building’s shape or orienting it to face south to use sunlight for energy or lighting. Even in cities with limited space, these methods can still help reduce environmental harm.

Goals of green building

The idea of sustainable development began in the 1960s and 1970s because of problems with energy, especially fossil fuels, and pollution. A book called Silent Spring by Rachel Carson, published in 1962, was one of the first to describe sustainable development in the context of green building. The green building movement in the United States started because people wanted to build homes and structures that used less energy and were better for the environment. There are many reasons to build green, such as helping the environment, saving money, and improving people’s lives. Today, sustainability efforts focus on combining different ideas to create new buildings and improve old ones. This method, also called sustainable design, connects the building’s life cycle with each green practice to work together effectively.

Green building uses many practices and skills to reduce or stop the harm buildings cause to the environment and people’s health. It often uses renewable resources, like sunlight through solar panels or green roofs with plants. Other methods include using materials that are better for the environment or using gravel or special concrete that helps water return to the ground.

Even though the tools and methods used in green building change over time and vary by region, some basic ideas stay the same. These include designing buildings to use space well, saving energy and water, using materials wisely, improving indoor air quality, maintaining buildings efficiently, and reducing waste and harmful chemicals. The main goal of green building is to improve one or more of these ideas. When green practices work together, they can have an even bigger positive effect.

On the artistic side, green architecture aims to create buildings that match the natural surroundings. Key steps in designing sustainable buildings include using materials from local sources, reducing energy needs, improving systems, and creating energy on-site, like using solar power.

A life cycle assessment (LCA) helps look at all the environmental, social, and economic effects of a building from the beginning to the end of its life. This includes steps like getting raw materials, making the building, using it, and recycling or disposing of it. Factors considered include energy used to make materials, pollution, and waste.

In recent years, green building has moved away from telling people what to do and instead focuses on testing how well buildings work using LCA. While LCA is widely seen as the best way to study environmental effects, it is not always required by green building standards. Some systems, like Green Globes and LEED, use LCA in certain ways, but not all. In California, LCA is included as a voluntary part of building rules.

Although LCA can be complex, groups like BRE in the UK and Athena Sustainable Materials Institute in North America are working to make it easier for designers to use. In the UK, the BRE Green Guide rates 1,500 building materials based on LCA.

Every building project starts with planning and design. These early steps have the biggest impact on a building’s cost and how well it works. When designing buildings that are good for the environment, the goal is to reduce the harm caused during every stage of the building’s life.

Building projects are not as simple as making products in a factory. Each building is different, and they are made of many materials and parts. Small changes in the design can affect the building’s impact on the environment over time.

Green buildings often use methods to save energy, including the energy used to make and transport materials and the energy needed to heat or power a building. As buildings use less energy during use, the energy used to make them becomes more important. Studies show that buildings made mostly of wood use less energy than those made of brick, concrete, or steel.

To save energy, designers make sure buildings are airtight and use high-quality windows and insulation. They also use passive solar design, which means placing windows and walls to let in sunlight in winter and block it in summer. Using natural light through smart window placement reduces the need for electric lights. Solar water heating also helps save energy.

Producing energy on-site using solar, wind, water, or plants can greatly reduce a building’s environmental impact. However, adding energy systems is usually the most expensive part of a building.

Energy efficiency in green buildings can be tested using numbers or non-numbers. Tools like computer models and statistical methods help evaluate how well buildings use energy.

In a report from April 2024, the International Energy Agency (IEA) said buildings use about 30% of the world’s energy and more than 50% of electricity. It noted that heat pump sales tripled between 2015 and 2022, and electric cars made up 20% of car sales in 2023. China’s electricity needs could double by mid-century, and India’s air conditioner use might increase tenfold by 2050. Efficient practices could cut this demand in half. By 2050, smart energy use might lower electricity bills by 7% to 12% in wealthy countries and nearly 20% in poorer ones. Smart devices could nearly double by 2030. The United States might reduce electricity use by 116 gigawatts through these efforts.

Cost and payoff

The most common concern about building environmentally friendly structures is the cost. Solar panels, new appliances, and modern technology often require more money upfront. However, most green buildings cost about 2% more initially but save 10 times that amount over the building’s lifetime. Studies show that over 20 years, the financial savings from green buildings usually cover the extra cost 4 to 6 times over. Additionally, green buildings reduce greenhouse gases and pollutants, which helps improve the health of nearby communities and the environment. The challenge is that some people focus on the initial cost instead of the long-term savings. These savings come from using utilities more efficiently, which lowers energy bills. It is estimated that different industries could save $130 billion on energy costs over time. Also, workers or students in green buildings may be more productive, which adds to the savings.

Research has shown that green buildings can improve worker productivity. Studies indicate that employees who enjoy their workspace tend to be more productive. Specific features of green buildings, such as better lighting, fewer pollutants, improved ventilation, and non-toxic materials, can greatly affect productivity. In "The Business Case for Green Building," the U.S. Green Building Council explains that commercial buildings that use energy-efficient upgrades can improve worker health and productivity. People in the U.S. spend about 90% of their time indoors, and studies show that indoor pollutant levels can be up to 10 times higher than outdoor levels. LEED-certified buildings are designed to have cleaner and healthier indoor air, which benefits those who live or work there.

Over a 20-year period, some green buildings have returned $53 to $71 per square foot of investment. Studies of the commercial real estate market also show that buildings with LEED or Energy Star certifications often have higher rental prices, higher sale prices, and higher occupancy rates. These buildings also have lower capitalization rates, which may suggest they carry less investment risk.

Regulation and operation

Because more people are interested in green building ideas, many groups have created standards, rules, and rating systems for use by government officials, builders, and people who buy homes. In some cases, these rules are written so local governments can use them as laws to help reduce the harm buildings cause to the environment in their area.

Green building rating systems, such as BREEAM (United Kingdom), LEED (United States and Canada), DGNB (Germany), CASBEE (Japan), VERDE (Spain), and GRIHA (India), help people understand how well a building protects the environment. These systems give points for optional building features that support green design in areas like the building's location and site care, saving water, energy, and materials, and improving comfort and health for people inside. The number of points usually shows how well the building performs.

Green building rules and standards, like the International Code Council's draft International Green Construction Code, are sets of rules made by groups that create standards. These rules set the lowest requirements for parts of green building, such as materials or heating and cooling systems.

The new version of the European Construction Products Regulation (PCR) includes parts about looking at a product's whole life and checking its environmental effects using the "System 3+" method.

Some important tools used today are:

• United States: International Green Construction Code (IGCC)

Green neighborhoods and villages

At the start of the 21st century, people began using the ideas of green building for not only single buildings but also for neighborhoods and villages. The goal is to create neighborhoods and villages that produce all the energy they need on their own. These areas will reuse waste, use eco-friendly transportation, and grow their own food. Green villages are being seen as a way to spread out sustainable climate practices, which could be especially helpful in places with many small villages, like India, where 74% of the population lives in more than 600,000 villages.

International frameworks and assessment tools

The IPCC Fourth Assessment Report

Climate Change 2007, the Fourth Assessment Report (AR4) of the United Nations Intergovernmental Panel on Climate Change (IPCC), is the fourth in a series of reports. The IPCC was created by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP) to study scientific, technical, and economic information about climate change, its possible effects, and ways to adapt to or reduce its impact.

UNEP and Climate Change

The United Nations Environment Programme (UNEP) helps societies move toward using less carbon, supports efforts to prepare for climate challenges, improves understanding of climate science, and informs the public about the global issue of climate change.

The Greenhouse Gas Indicator: UNEP Guidelines for Calculating Greenhouse Gas Emissions for Businesses and Non-Commercial Organizations

Agenda 21 is a program by the United Nations (UN) focused on sustainable development. It is a detailed plan for action at global, national, and local levels by UN organizations, governments, and groups that affect the environment. The number 21 refers to the 21st century.

The International Federation of Consulting Engineers (FIDIC) Project Sustainability Management Guidelines were created to help engineers and other project stakeholders set goals for sustainable development that benefit society. The process also helps match project goals with local needs and priorities, and supports measuring progress on projects.

The Project Sustainability Management Guidelines are organized under three main areas: Social, Environmental, and Economic. Each sub-topic includes a key indicator and guidance on how it applies to a specific project.

The Sustainability Reporting Framework provides guidance for organizations to share information about their sustainability performance. It also offers a standard, easy-to-understand framework for stakeholders to compare and interpret reported data.

The Reporting Framework includes the core Sustainability Reporting Guidelines, along with Protocols and Sector Supplements. These Guidelines are the basis for all reporting and outline general content relevant to all organizations, regardless of size or industry. They include principles, guidance, and standard information, such as indicators, to help organizations share sustainability data in a voluntary and flexible way.

Protocols support each indicator in the Guidelines. They define key terms, explain how to collect data, describe the scope of each indicator, and include other technical details.

Sector Supplements address the need for different rules in different industries. They help the core Guidelines by focusing on unique sustainability challenges in areas like mining, automotive, banking, and public agencies.

The IPD Environment Code was introduced in February 2008. It is a global standard for measuring the environmental performance of corporate buildings. Its goal is to accurately track and manage the environmental effects of buildings and help property managers share clear, comparable information about building performance worldwide. The Code covers many building types, such as offices and airports, and supports:

• Developing an environmental strategy
• Supporting real estate planning
• Sharing a commitment to improving the environment
• Setting performance goals
• Creating plans for environmental improvement
• Measuring and evaluating performance
• Assessing the life cycle of buildings
• Managing building purchases and sales
• Managing suppliers
• Using information systems and data
• Following environmental regulations
• Setting team and personal goals

IPD estimates it will take about three years to collect enough data to create a reliable baseline for measuring environmental performance across a typical corporate building portfolio.

ISO/TS 21931:2006, Sustainability in building construction—Framework for methods of assessment for environmental performance of construction works—Part 1: Buildings, provides a general guide for improving the quality and consistency of methods used to evaluate the environmental performance of buildings. It outlines important factors to consider when assessing the environmental impact of new or existing buildings during design, construction, operation, renovation, and demolition. It is not a complete assessment system itself but is meant to be used with the principles in the ISO 14000 series of standards.

Development history

• In the 1930s, Iceland began using hot water from geothermal sources to heat homes in a system called district heating.
• In the 1960s, American architect Paul Soleri introduced a new idea for buildings that work with nature, called ecological architecture.
• In 1969, American architect Ian McHarg wrote the book Design Integrates Nature, which marked the start of ecological architecture.
• In the 1970s, the energy crisis led to the development of new building technologies, such as solar, geothermal, and wind energy. Energy-efficient buildings became a leading example of building development.
• In 1975, the Swiss PLENAR-group shared the idea of energy-efficient homes in the publication PLENAR: Planning-Energy-Architecture.
• In 1980, the World Conservation Organization first used the term "sustainable development." At the same time, energy-saving building systems improved and became widely used in countries like Germany, Britain, France, and Canada.
• In 1982, Per and Maria Krusche and others published an ecological approach to architecture in Ökologisches Bauen (ecological buildings) for the German Federal Environment Agency.
• In 1987, the United Nations Environment Program released the report Our Common Future, which defined the idea of sustainable development.
• In 1990, the first green building standard in the world was introduced in the United Kingdom.
• In 1992, the United Nations Conference on Environment and Development promoted sustainable development, leading to the growth of green buildings as a major direction for building development.
• In 1993, the United States created the Green Building Association.
• In 1996, Hong Kong introduced green building standards.
• In 1999, Taiwan introduced green building standards.
• In 2000, Canada introduced green building standards.
• In 2005, Singapore started the BCA Green Building Mark program.
• In 2015, based on research from the Berkeley National Laboratory, China implemented the Green Building Evaluation Standards.
• In 2021, the first low-cost and sustainable 3D-printed house made from a clay mixture was completed.

Green building by country

• Green building in Australia
• Green building in Bangladesh
• Green building in Germany
• Green building in France
• Green building in Israel
• Green building in South Africa
• Green building in the United Kingdom
• Green building in India
• Green building in the United States
• Green building in Canada
• The Model Home 2020 Project: Denmark, Austria, Germany, France, UK