Construction phase emissions significantly impact building carbon footprint
Category: Sustainability · Effect: Strong effect · Year: 2023
The construction phase of a building's life cycle can account for 20-50% of its total carbon emissions, with an average ratio of construction emissions to operational emissions of 0.62.
Design Takeaway
Integrate life cycle assessment early in the design process, paying close attention to the embodied carbon of materials and construction methods, not just operational energy use.
Why It Matters
This highlights that focusing solely on operational energy efficiency is insufficient for achieving true sustainability in the built environment. Designers and engineers must consider the embodied carbon within materials and the emissions generated during the construction process itself.
Key Finding
A significant portion of a building's total carbon footprint, between 20% and 50%, is generated during its construction, and for every unit of carbon emitted during operation, approximately 0.62 units are emitted during construction.
Key Findings
- The construction phase accounts for 20-50% of total carbon emissions over a building's life cycle.
- The average ratio of construction phase annual emissions to operation phase emissions is 0.62.
Research Evidence
Aim: What is the proportion of carbon emissions attributable to the construction phase versus the operational phase of buildings, and how do these proportions vary?
Method: Literature Review
Procedure: The researchers reviewed existing literature on green construction, focusing on carbon emissions, policies, models, life cycle assessment, and sustainable materials. They analyzed data on carbon emissions across the entire building life cycle, specifically extracting figures related to the construction phase and comparing them to operational emissions.
Context: Building and Construction Industry
Design Principle
Minimize embodied carbon through material selection and efficient construction practices.
How to Apply
When specifying materials for a new design project, research and compare the embodied carbon data for different options. Consider prefabrication or modular construction techniques that can reduce on-site construction time and associated emissions.
Limitations
The review synthesizes data from various sources, which may have differing methodologies for calculating emissions. The specific percentages can vary widely depending on building type, materials used, and construction techniques.
Student Guide (IB Design Technology)
Simple Explanation: When you build something, the actual building process creates a lot of pollution, not just when people use the building later.
Why This Matters: Understanding the construction phase's impact helps you make more sustainable design choices for your projects, leading to a lower overall environmental footprint.
Critical Thinking: If the construction phase is so impactful, what are the most effective strategies for designers and engineers to mitigate these emissions, and how can these strategies be realistically implemented in diverse construction projects?
IA-Ready Paragraph: Research indicates that the construction phase of a building's life cycle is a significant contributor to its overall carbon footprint, accounting for 20-50% of total emissions. This underscores the importance of considering embodied carbon in material selection and optimizing construction processes to achieve genuine sustainability.
Project Tips
- When researching materials, look for their 'embodied carbon' figures.
- Consider how your chosen construction method might affect emissions.
How to Use in IA
- Cite this research when discussing the environmental impact of your design choices, particularly regarding material selection and construction methods.
Examiner Tips
- Demonstrate an understanding that sustainability extends beyond operational efficiency to include the entire life cycle of a product or building.
Independent Variable: Building life cycle phase (construction vs. operation)
Dependent Variable: Carbon emissions (percentage of total)
Controlled Variables: Building type, material composition, construction methods, geographical location
Strengths
- Provides a crucial perspective on the often-overlooked construction phase emissions.
- Synthesizes global data and policy frameworks.
Critical Questions
- How can we standardize the measurement of embodied carbon across different materials and construction techniques?
- What are the economic trade-offs associated with adopting low-carbon construction materials and methods?
Extended Essay Application
- Investigate the embodied carbon of materials used in a specific local construction project and propose alternative, lower-carbon options.
Source
Green construction for low-carbon cities: a review · Environmental Chemistry Letters · 2023 · 10.1007/s10311-022-01544-4