Green BIM: what it is and why it matters
How Building Information Modeling is contributing to the construction of green building projects and why it is important in sustainable design
In recent years, the topic of energy efficiency and energy consumption has become increasingly important worldwide.
It is known that climate change depends on many factors, including cities with their urban heat islands, factories and in general carbon emissions from buildings. Consider that more than 1/3 of the world’s energy consumption is due to buildings and construction works, and 1/4 of carbon emissions are due to conventionally built buildings.
In this context, it is clear that Green Buildings can significantly reduce this impact and being a viable solution.
Sustainability is now recognised as one of the fundamental requirements for the development of contemporary society and cities. It is therefore essential to apply sustainability strategies within the building industry to reduce the buildings energy requirements and limit their environmental impact.
Among the strategies to ensure sustainable design are the assessment methods for green buildings (BREEAM, LEED, LCA etc.), which suggest the actions necessary to reduce the environmental impact of buildings.
In order to achieve optimal results, it is also important that these actions are taken at the preliminary design stage.
This is undoubtedly complex when using traditional 2D design software which only allows the energy analysis to be carried out at the end of the design process, limiting the possibility of improving the energy performance of the building.
The BIM design process allows each stage of the design (and post-construction) process to be monitored and sustainability strategies to be integrated from the beginning of the design process.
As we know Building Information Modeling (BIM) is a collaborative working process that uses digital models to support design and VDC (Virtual Design Construction) that can simplify the project delivery workflow and improve building performance.
Specifically, the use of BIM to provide data for energy performance and sustainability assessment of buildings is known as Green BIM.
BIM-based energy analysis can help design teams examine and create optimised energy efficiency, predicting the outcomes of construction to minimise its impact on the environment throughout its lifecycle.
Green BIM therefore includes BEM (Building Energy Modeling), a method based on the creation of a model for energy analysis derived from a BIM model which, for this purpose, is previously exported in an interchange format, usually the IFC format.
BIM helps to optimise, at the preliminary stage, the orientation and shape of the building, the relationship between walls and windows, solar inputs and, at the execution stage, natural lighting, water management, energy performance and plant choices, and the sustainability of materials.
Thanks to this, and based on the principles of sustainable design, projects undergo scientific modelling during the early stages of design as parts are refined:
- daylight and energy are studied throughout the process
- energy consumption is minimised and renewable strategies are found to meet the needs of the building
- water use and waste is minimised or eliminated through modelling and design of the building and site
- construction waste is identified and redirected as a source for other users and products.
The entire manufacturing and construction process is anticipated and guided as critical design elements.
All these aspects require the use of software to map the parameters and data to be shared to ensure interoperability without loss of information, as well as the choice of the most appropriate tools to guarantee reliable results.
The verification of environmental criteria and the compliance of the project with certain requirements of the different sustainability protocols can be done through a collaborative process, where specific workflows can be developed to ensure that environmental criteria are reflected in the performance characteristics of the project.
Improving the quality of architecture (in both the design and construction phases) depends on the ability of designers to take into account the entire life cycle of buildings and on the willingness of stakeholders to create virtuous cooperation: every decision, regardless of when it is made, cannot be separated from a careful assessment of the repercussions it has on the entire system.
Cooperation between stakeholders becomes, therefore, a key element in achieving new levels of architectural quality; simultaneous cooperation, as the sequential processing of design and construction activities is replaced by real-time comparison between different skills.
Find out how simple it is to collaborate effectively with different teams: discover usBIM
Why is BIM modelling important in sustainability?
- It provides transparency and clarity at every stage
- It gives in-depth knowledge of materials technology
- It is an efficient design process on and off site
- It monitors performance before and after occupancy
- It minimises waste and therefore saves costs
- It improves and optimises design functionality through its comprehensive operation.
In the construction industry there must be a continuous drive towards sustainable design.
Typically, energy consumption software are used to verify that a project meets sustainability requirements.
If the results of the verification show that the energy performance of the building is inadequate, designers have the possibility to modify the design features that negatively affect the results. However, the possibility of verification and possible modification is limited to the design phase.
It is not taken into account that, due to maintenance activities or the operational status of the building, design features may be altered, compromising the energy performance of the building (and therefore its sustainability).
One of the major advantages of BIM is the ability to manage all phases of the project lifecycle (from construction, through operation to decommissioning) mitigating time and costs due to errors or loss of data.
The correct use of BIM should not be seen as being focused mainly, if not exclusively, on improving architectural design; rather it should be applied by the entire project team at every stage of design, not least that of improving the energy performance of buildings (Green BIM).