The building industry is one of the most polluting industries in the world. A considerable amount of non-renewable resources are extracted for the building materials. Besides, a lot of energy is consumed during the lifetime of the buildings. Finally, when they are destroyed, a huge amount of waste is produced, and most of it cannot be reused or recycled at all. In the meantime, the world population is expected to grow by 3 billions in the coming decades! This means we will need more houses, more hospitals, more schools, and so on. But we simply cannot continue like before. We will see in this article that the Building Information Modeling (BIM) process can help us with that matter. This process can help architecture, engineering and construction (AEC) workers to build more green buildings. Actually, BIM is a perfect process for the mass adoption of green buildings.
But what is BIM exactly?
BIM is a process which is based on a 3D model representation of the building. This digital process gives AEC professionals all the tools they need so they can plan, design, build and manage buildings and infrastructure.
With BIM, all the stakeholders can jointly take design decisions, improve the building performance and, more generally, collaborate throughout the whole building lifecycle. Everybody share the same centralized 3D model and all its related information. Traditional designing and cooperation approaches involve a lot of non centralized exchanges between the different stakeholders. This is time-consuming, and a lot of errors and communication misunderstanding can happen and result in delays and design errors. Building Information Modeling changes that.
Green BIM (or BIM in green building) is a process helping AEC workers to increase sustainability in the construction industry. With this, they can integrate and analyze environmental issues in their design and throughout the life cycle of buildings. Green BIM is made possible by integrating sustainability assessment methods within BIM.
Sustainable assessment methods, you said?
Let’s first recall what is a green building. A green building follows these six basic principles:
- Resource consumption is minimized,
- Resource reuse is maximized,
- Renewable or recyclable resources are used,
- Natural environment is protected,
- Indoor and outdoor environment is healthy and non-toxic,
- Quality is pursued in creating the building,
Nowadays, there are several sustainability assessment methods permitting to follow these six principles. These methods are guidelines to implement and spread sustainable measures in construction projects. With these, the sustainability level of the buildings is also be evaluated and monitored.
Three famous sustainability assessement methods are:
- Leadership in Energy and Environmental Design assessment method (or LEED),
- Building Research Establishment Environmental Assessment Method (or BREEAM),
To better understand what this is about, let’s take a look at the LEED 4.1 Residential Single Family credit system (assessement extracted here).
The following criteria must be respected (when « required ») or are encouraged to be respected (with credit points):
Part1: Integrative process
- Maximize opportunities for cost-effective adoption of integrative green design and construction strategies. (2 points),
Part 2: Location and transportation
- Minimize the environmental damage of land development practices by building homes in LEED for Neighborhood Development–certified communities. (10 points),
- Encourage construction in environmentally preferable locations and avoid development of sensitive lands (6 points),
- Conserve land and promote livability, transportation efficiency, and walkability by creating compact communities (1 point),
- Encourage daily walking and bicycling and to reduce vehicle miles traveled (VMT) and automobile dependence (1 point),
- Eeduce pollution and land development effects from automobile use (2 points),
- Reduce the environmental impact of the development footprint (required),
Part 3: Sustainable sites
- Reduce pollution from construction activities by controlling soil erosion, waterway sedimentation, and airborne dust (required),
- Reduce rainwater runoff volume from the site (2 points),
- Minimize pest problems and risk of exposure to pesticides (2 points),
Part 4: Water efficiency
- Reduce demand for water through high-efficiency fixtures and efficient landscaping practices (required),
- Support water efficiency efforts by monitoring and benchmarking water use over time (required),
- Reduce demand for water through high-efficiency fixtures and efficient landscaping practices (15 points),
- Minimize indoor demand for water through high-efficiency fixtures and fittings (11 points),
- Reduce outdoor water consumption through efficient landscaping practices (4 points),
Part 5: Energy and atmosphere
- Improve the building’s overall energy performance and reduce its greenhouse gas emissions (required),
- Support energy efficiency efforts by monitoring and benchmarking energy use over time (required),
- Sustain the performance of the home by training its occupants in the operation and maintenance of LEED features and equipment (required),
- Improve the home’s overall energy performance and reduce its greenhouse gas emissions (36 points),
- Reduce energy consumption and the burden on water supply and waste water systems by increasing the efficiency of hot water distribution. (2 points),
- Reduce energy consumption by ensuring that heating and cooling systems operate at peak efficiency (1 point),
- Reduce stratospheric ozone depletion (1 point),
Part 6: Materials and resources
- Encourage environmentally responsible forest management (required),
- Promote durability and performance of the building enclosure and its components and systems through appropriate design, materials selection, and construction practices (required),
- Promote enhanced durability and high performance of the building enclosure and its components and systems through appropriate design, materials selection, and construction practices (3 points),
- Increase demand for products or building components that minimize material consumption through recycled and recyclable content, reclamation, or overall reduced life-cycle impacts (5 points),
- Reduce construction waste generation and to reuse and recycle debris (2 points),
- Conserve resources by reducing the use of unnecessary framing materials (2 points),
Part 7: Indoor environemental quality
- Reduce moisture problems and occupants’ exposure to indoor pollutants from kitchens, bathrooms and other sources by exhausting pollutants to outside and ventilating with outdoor air (required),
- Limit the leakage of combustion gases into the occupied space of the home. (required),
- Reduce occupants’ exposure to indoor pollutants originating from an adjacent garage (required),
- Reduce occupants’ exposure to radon gas and other soil gas contaminants (required),
- Protect occupants’ health by reducing particulate matter from the air supply system (required),
- Limit occupants’ exposure to indoor air pollutants by minimizing the transfer of air between units (required),
- Minimize moisture problems and occupants’ exposure to indoor pollutants through enhanced exhaust and ventilation systems (3 points),
- Reduce occupants’ exposure to indoor airborne contaminants through source control and removal (3 points),
- Improve thermal comfort and energy performance by ensuring appropriate distribution of space heating and cooling in the home (6 points),
- Reduce occupants’ exposure to airborne chemical contaminants through product selection (4 points),
Part 8: Innovation
- Maximize opportunities for integrative, cost-effective adoption of green design and construction strategies (required),
- Encourage exceptional performance for current credits and promote innovative performance in pioneering areas (5 points),
- Encourage the project team integration required by a LEED project and to streamline the application and certification process (1 point),
Part 9 : Regional priority
- Address geographically specific environmental, social equity, and public health priorities (4 points),
After having added up all the credit points you have your total can match four level of certifications:
- 40 to 49 points: « LEED certified »,
- 50 to 59 points: « LEED silver »,
- 60 to 79 points: « LEED gold »,
- Equal or more than 80 points: « LEED platinium »,
The TAIPEI 101 skyscrapper is a notorious example of a « LEED platinium » certified green building.
But assessing the sustainability of a building using the LEED method (or other) is time-consuming. A lot of different data as well as a lot of calculations are necessary. Unfortunately, performing such assessment is often incompatible with the deadlines of this industry. Besides, after each project modification, AEC workers have to repeat the entire assessment.
Fortunately, BIM, with all the data it gathers, can ease the sustainable assessment of a building. This process makes sustainability assessment simpler and more repeatable. BIM is clearly a solution for the mass adoption of green buildings around the world. Here, computing the credits and verifying the prerequisites can almost be performed automatically. Therefore this step will not threaten deadlines any longer and will hopefully become a standard. The goal is clearly that the sustainability assessment of buildings become a standard design step for AEC workers.
However there are still some work to do until Green BIM becomes a mass adopted tool. There are still some interoperability problems between BIM tools and sustainability tools. There is a lack of standards. The actual BIM tools are not yet fully adapted for green buildings. On top of that, there is a low industrial acceptance for the adoption of Green BIM.
BIM for the mass adoption of green buildings.
Although, Green BIM is a perfect process to help AEC workers to design and build green buildings in mass. Green BIM is not yet a reality in the construction industry. Indeed, there are still some technical issues to solve.
Technically, the above mentioned limitations of nowadays’ BIM with respect to green buildings are not insurmountable. So we can therefore hope to benefit from this very soon. Then, AEC workers all around the world will be able to use BIM for the mass adoption of green buildings.
The BIM process is not yet adopted by all AEC workers around the world. Therefore, a broader adoption of the BIM process will be the first step towards a mass adoption of the Green BIM process around the world.
I hope you enjoyed this article! As usual. I would be happy to read your suggestions in the comments to make this article more useful for you! And if you notice a dead link or an outdated information, please let me know!