The LEED certification is globally recognized, but the WELL certification has also gained importance in recent years. Both rating systems measure building performance across several categories, and the score achieved determines the certification level. While LEED gives more weight to energy efficiency and environmental sustainability, WELL focuses on human well-being, hence its name.
WELL normally has three certification levels, and their names and scores resemble the upper three levels of LEED. The main difference lies in the performance requirements, and how points are earned.
Core and shell projects also have access to the WELL Bronze level, which is is below Silver with a minimum score of 40. This pathway is only available if at least 75% of the floor space is composed of tenant spaces and common areas.
The WELL certification is based on 11 performance categories: Air, Water, Nourishment, Light, Movement, Thermal Comfort, Sound, Materials, Mind, Community, Innovations. Like in the LEED system, there are mandatory credits, and points are earned with the optional credits. A building cannot receive the WELL certification if it misses at least one mandatory credit, regardless of the score achieved.
WELL gives great importance to air quality, since people spend around 90% of their time indoors in modern society. On average, each person breathes around 530 cubic feet of air per day, hence the importance of having clean and healthy air. The effects of air pollutants are highly variable: while some substances only cause irritation, others like carbon monoxide are lethal.
The Air category has 4 mandatory requirements and 18 possible points.
Humans consume water in smaller amounts than air, but it is also vital. The US Institute of Medicine recommends a daily water intake 3.7L for men and 2.7L for women. The WELL certification mandates a drinking water source within the project boundary, approved with adequate testing.
There are 3 mandatory requirements in the Water category, and 9 possible points.
The Nourishment category is a key difference between WELL and LEED, and it focuses on the consumption of healthy food. The certification covers this topic in depth, dealing with aspects like portion sizes, responsible food sourcing, preparation and availability. WELL promotes healthy foods like fruits and vegetables, while helping occupants avoid highly processed foods and other harmful products.
There are 2 mandatory requirements in the Nourishment category, and up to 17 points.
Lighting has a significant impact on physical and mental health. When lighting is designed according to human needs and the circadian rhythm, it leads to healthier sleep patterns and improved productivity. On the other hand, inadequate lighting can be disruptive for sleep and health in general. WELL emphasizes natural lighting, glare prevention, light quality and controls for occupants.
There are 2 mandatory requirements in the Light category, and up to 14 points.
The WELL framework considers the negative impact of a sedentary lifestyle, and it promotes movement and physical activity within the building. In particular, sedentary lifestyles have been associated with cardiac issues and increased mortality. WELL promotes pedestrian-friendly buildings and ergonomic furniture, among other improvements.
There are 2 mandatory requirements and up to 20 points in the Movement category.
WELL emphasizes HVAC design practices that provide a comfortable temperature, but also the flexibility to meet individual preferences. Air temperature not only affects comfort, but also health and productivity. Excessive heating or cooling are not only uncomfortable, but also a waste of energy. In most residential and commercial buildings, HVAC accounts for over 50% of energy expenses.
There is 1 mandatory requirement and up to 12 points in the Thermal Comfort category.
Sound is often overlooked when designing buildings, but it has a huge impact on comfort and productivity. WELL promotes building designs that mitigate noise sources, such as traffic and mechanical equipment. Uncontrolled noise can lead to poor sleep, reduced performance and stress. In great part, noise can be mitigated with a smart layout and acoustic materials.
There is 1 mandatory requirement in the Sound category, and up to 11 points.
WELL promotes the use of safe materials, avoiding those than emit hazardous substances. Environmental impact is considered over the entire life cycle of materials, including extraction and disposal. Renovations and existing buildings require special caution: there may be old and hazardous materials that are no longer used, such as asbestos.
The Materials category has 3 mandatory requirements and 22 points.
WELL gives importance to mental health, since it influences quality of life and productivity. It is estimated that depression and anxiety have cost the global economy $1 trillion, in addition to their negative impact on well-being. WELL also focuses on the prevention of substance abuse, which is closely related with mental health.
There are 2 mandatory requirements in the Mind category, and up to 24 points.
Since building occupants share indoor and outdoor spaces, they eventually form a community. WELL promotes a collaborative community that looks after its members. Being a good neighbor is also important, since buildings are in constant interaction with their surroundings. WELL also promotes health services, new parent support, civic engagement and transparency.
There are 3 mandatory requirements and 31 points under the Community concept.
Just like the LEED system, WELL gives points for innovative solutions not covered under the mandatory requirements and optional credits. Innovation points can also be earned by:
There are no mandatory requirements under Innovation, and up to 18 points can be collected.
WELL and LEED are not competing programs, and they can complement each other. A building with both certification is energy efficient and environmentally friendly, while promoting well-being and health among its occupants.