Sustainable construction reduces the environmental impact of the construction sector, but it also makes sense as a business decision. When sustainability is considered during the design and construction process, buildings achieve a lower cost of ownership throughout their useful life. Green buildings also provide indoor environmental quality, which is beneficial to human health and comfort. Occupants save on medical expenses when the built environment is healthy and businesses can achieve greater productivity.
Any project can utilize sustainable construction practices to reduce its environmental footprint and improve the built environment. However, a green building certification shows that the project has been approved by an impartial and recognized organization. This brings several advantages:
- A green building certification can attract tenants as they expect operational savings and an improved indoor environment.
- Depending on where the building is located, a green certification may earn financial incentives from the local government or utility companies.
- Companies with certified green buildings can improve their image as corporate citizens.
- Sustainable design practices can achieve superior performance in certified buildings, provided the process has been approved by a qualified external entity.
Improve indoor air quality and reduce your utility bills with green building design.
Many green building certifications have been developed around the world. They use different performance categories and scoring systems, but they have a common goal – to make the built environment more sustainable. This article provides an overview of various green certifications.
LEED: Leadership in Energy and Environmental Design
LEED is one of the most popular green building certifications, especially in North America, and was developed by the US Green Building Council. To obtain a LEED rating, a building must meet several mandatory requirements while earning points in different performance categories:
- Location and Transport
- Sustainable Locations
- Water efficiency
- Energy and Atmosphere
- Materials and Resources
- Indoor Environmental Quality
- Innovation
- Regional Priorities
A construction project must earn at least 40 points to achieve LEED certification. There are also Silver, Gold and Platinum certifications with minimum scores of 50, 60 and 80. Mandatory requirements must be met regardless of the score, otherwise the building cannot be certified.
BREEAM: Building Research Establishment Environmental Assessment Method
Published in 1990 by the United Kingdom's Building Research Institution, BREEAM was the world's first green building certification system. BREEAM considers the following performance categories when assessing a building:
- Energy
- Health and wellness
- Innovation
- Land use
- Materials
- Management
- Pollution
- Transport
- Waste
- Water
The BREEAM scoring system uses six stars, which describe the building's level of performance: Acceptable (1), Pass (2), Good (3), Very Good (4), Excellent (5) and Excellent (6). The Acceptable score (1 star) can only be obtained for existing buildings in use. For all other project types, the minimum certification score is Pass (2 stars).
The WELL construction standard
WELL is a unique certification because it focuses on the health and well-being of occupants, as its name implies. There are performance requirements as with any building certification system, but these are based on creating ideal conditions for people, giving less priority to the building itself. The current version of WELL (v2) considers the following performance categories:
- Air
- Water
- Food
- Light
- Movement
- Thermal comfort
- Sound
- Materials
- Mind
- Community
WELL certification has mandatory prerequisites, just like LEED, and the building must score at least 50 points to be certified. However, core and shell projects can be certified with just 40 points. The four certification levels are Bronze, Silver, Gold and Platinum; which correspond to minimum scores of 40, 50, 60 and 80.
The first version of WELL was more rigorous, with 41 mandatory preconditions and 59 optimizations to choose from. WELL, v2 is more flexible, reducing the preconditions to 23 and increasing the optimizations to 92.
CASBEE: Comprehensive Assessment System for Built Environment Efficiency
CASBEE is a green building certification developed by the Japan Sustainable Building Consortium (JSBC). CASBEE analyzes a building's performance across four categories, which are used to calculate a metric called Built Environment Efficiency (BEE):
- Energy efficiency
- Resource efficiency
- Local environment
- Internal environment
CASBEE certification provides four assessment tools for different stages of the building life cycle: Pre-Design, New Construction, Existing Building and Renovation. CASBEE can also be applied at different scales: Housing, Construction, Urban Development and City.
Buildings can obtain five ratings based on the efficiency of the built environment: C (Poor), B- (Slightly Poor), B+ (Good), A (Very Good) and S (Superior). CASBEE was originally developed for use only in Japan, but there is growing interest in certification internationally.
ENERGY STAR certified
The ENERGY STAR program was created by the US Environmental Protection Agency. Certification is typically associated with energy-efficient products, but can also be applied to entire buildings. Unlike other certification systems, ENERGY STAR focuses exclusively on energy efficiency:
- Building owners report energy consumption using a tool called Portfolio Manager.
- The energy efficiency of the building is compared with others of the same type, under the same climatic conditions.
- The ENERGY STAR score is a percentile. For example, a building with a score of 80 is in the top 20% and a building with a score of 95 is in the top 5%.
- The minimum score for an ENERGY STAR certified building is 75, meaning it must be in the top 25% of most efficient buildings of its type.
Building ENERGY STAR scores are recalculated every year based on the most recent performance data. This means buildings must remain in the top 25% to maintain certification. Additionally, submitted data must be validated by a Professional Engineer or Registered Architect.
Green Globes
The Green Globes certification was developed by the Green Building Initiative, using BREEAM as its main reference. Green Globes apply to both new construction and existing buildings and consider the following performance categories:
- Project management
- Energy
- Water
- Materials and Resources
- Emissions
- Internal environment
- site
A building can earn up to 1000 points, and the minimum score for certification is 35%. There are four levels of certification, which depend on the score obtained: One Green Globe (35-54%), Two Green Globes (55-69%), Three Green Globes (70-84%) and Four Green Globes (85-84% ). 100%).
EDGE: Excellent Design for Greater Efficiency
EDGE certification was developed by the International Finance Corporation (IFC) and focuses on three areas: direct energy consumption, water consumption and energy embodied in building materials. Instead of providing specific requirements, EDGE certification requires a 20% reduction in all three areas of activity.
There are two additional levels beyond EDGE certification that are achieved with improved performance. The EDGE Advanced level has the same onboard water and power consumption requirements, but power consumption must be reduced by at least 40%. The next level is Zero Carbon, with the same requirements as EDGE Advanced, and the building must also become fully carbon neutral with renewable energy and carbon offsets.
IFC developed EDGE to meet the needs of developing countries, where complex certifications with detailed requirements are more difficult to obtain.
NGBS: The National Green Building Standard
The NGBS was developed by the National Association of Home Builders and focuses on residential properties such as single-family homes and apartments. NGBS covers six areas of activity:
- Energy efficiency
- Water efficiency
- Resource efficiency
- Batch development
- Operation and maintenance
- Indoor environmental quality
NGBS certification has four levels: Bronze, Silver, Gold and Emerald. The certification level is determined by the project's scores in the six performance categories.
Living Building Challenge
The Living Building Challenge is more demanding than other certifications, as it aims to completely eliminate environmental impacts. To obtain Living Building Certification, a project must meet 20 requirements (called Imperatives) divided into seven performance categories (called Petals):
- Place: Ecology, urban architecture, habitat exchange, life on a human scale
- Water: Responsible use of water, positive liquid water
- Energy: Energy + carbon reduction, net positive energy
- Health and happiness: Healthy indoor environment, healthy indoor performance, access to nature.
- Materials: Responsible materials, red list, responsible sourcing, living economy sourcing, net positive waste
- Equity: Universal access and inclusion
- Beauty: Beauty + biophilia and Education + inspiration
The Petal Certification is a less demanding version of the Living Building Certification as it only requires 3 of the 7 categories. However, one of the categories must be Water, Energy or Materials. The Living Building Challenge also includes the Core Green Building Certification, which requires only 10 of the 20 Imperatives, called Core Imperatives:
- Ecology of the place
- Life on a human scale
- Responsible use of water
- Energy + carbon reduction
- Healthy indoor environment
- Responsible materials
- universal access
- Inclusion
- Beauty + biophilia
- Education + inspiration
Furthermore, projects can apply for a Zero Energy Certification or a Zero Carbon Certification. Zero Energy Certification requires that buildings generate all their energy on site, without using combustion. On the other hand, Zero Carbon Certification establishes energy efficiency and carbon neutrality requirements.
Conclusion
Energy efficiency and other resource conservation measures mitigate the environmental impact of the construction sector while reducing ownership costs. However, a green certification proves that the building has a sustainable design. Real estate developers can certify their projects to attract tenants, and companies in general can improve public perception by certifying their buildings.
The construction sector is responsible for 40% of global energy use and emissions, and sustainable construction can significantly reduce its environmental impact. Green buildings also make sense for businesses: they have lower ownership costs and the improved indoor environment benefits human health and productivity.
