Journal of Architectural Engineering Technology
Open Access

Low-carbon materials, Sustainable construction, Green building, Geopolymer concrete, Carbon footprint, Life cycle assessment (LCA), Bio-based composites, Eco-friendly infrastructure, Climate-resilient buildings, Sustainable development goals (SDGs)

Introduction

The construction industry is a major contributor to global greenhouse gas (GHG) emissions, accounting for nearly 37% of global CO2 emissions when considering both operational and embodied carbon [1]. The urgent need to reduce carbon footprints has spurred the development and adoption of low-carbon construction materials [2]. This article explores the types, benefits, and challenges of low-carbon materials, providing insights into their environmental impact, lifecycle analysis, and real-world applications [3]. Additionally, it highlights policy frameworks and emerging technologies driving the transition toward greener construction practices. The construction sector plays a pivotal role in shaping global sustainability. However, its reliance on carbon-intensive materials, such as concrete, steel, and cement, contributes significantly to CO2 emissions [4]. According to the Global Alliance for Buildings and Construction, the embodied carbon from building materials accounts for 11% of global energy-related emissions. With the rising demand for infrastructure, the industry faces mounting pressure to adopt low-carbon alternatives to mitigate environmental impacts [5]. As the global community grapples with the escalating climate crisis, the construction industry stands at a critical crossroads. Buildings are responsible for nearly 40% of global carbon dioxide emissions, with a significant portion attributed to the embodied carbon locked within construction materials such as cement, steel, and aluminum [6]. Traditional construction methods, reliant on energy-intensive manufacturing processes and resource-heavy supply chains, have contributed significantly to environmental degradation, resource depletion, and global warming. In response, a growing movement within the building sector is turning toward low-carbon construction materials as a pivotal strategy for achieving sustainability goals, meeting regulatory mandates, and reshaping the future of the built environment [7]. Low-carbon construction materials refer to building products and technologies that produce significantly lower carbon emissions across their life cycle from raw material extraction and manufacturing to transportation, installation, use, and eventual disposal or reuse. These materials not only reduce embodied emissions but also often enhance energy efficiency during the operational phase of buildings. Examples include low-carbon cement alternatives (like geopolymer concrete and limestone calcined clay cement), recycled steel, cross-laminated timber, hempcrete, recycled aggregates, and bio-based insulation materials [8]. Many of these materials are not only carbon-efficient but also promote circular economy principles, encouraging reuse, recyclability, and minimal waste generation.

The transition to low-carbon construction materials is being propelled by a convergence of factors. Policy and regulatory frameworks, such as carbon pricing, building codes, and green certification programs, are increasingly requiring or incentivizing the use of low-emission materials. Technological innovation is making alternative materials more viable and cost-effective, while public awareness and market demand for green buildings are pushing developers to adopt more sustainable practices. Furthermore, the integration of life cycle assessment (LCA) tools and digital technologies like building information modeling (BIM) allows stakeholders to evaluate the environmental impact of materials early in the design phase, facilitating more informed decision-making.

However, the adoption of low-carbon construction materials is not without challenges. These include economic barriers, such as higher upfront costs and limited supply chains; technical limitations, such as variability in performance and lack of standardized testing; and institutional resistance, stemming from entrenched practices and insufficient awareness among architects, engineers, and contractors. Bridging these gaps will require a collaborative effort among governments, industry leaders, researchers, and communities.

This article explores the emerging landscape of low-carbon construction materials by examining their types, environmental and economic benefits, barriers to widespread adoption, and the innovations paving the way forward. By doing so, it aims to shed light on how these materials can transform the construction sector into a climate-resilient and resource-efficient industry, capable of supporting the planet's ecological limits while meeting the growing demand for housing and infrastructure. As nations strive to meet their net-zero emissions targets, low-carbon materials are not merely an option— they are an imperative for sustainable building practices in the 21st century and beyond.

Low-carbon construction materials

Low-carbon construction materials are products and substances specifically designed or manufactured to reduce GHG emissions throughout their lifecycle. This includes the extraction of raw materials, manufacturing, transportation, usage, and eventual disposal or recycling.

Reduced embodied carbon, lower CO2 emissions during production.

Energy efficiency, minimal energy consumption in manufacturing.

Circular economy compatibility, reusability, recyclability, and minimal waste.

Biodegradability, natural decomposition without harmful emissions.

Bio-based materials, bamboo, hempcrete, cork, and timber.

Recycled and reclaimed materials, recycled concrete aggregate (RCA), reclaimed wood, and recycled steel.

Low-carbon cement and concrete, geopolymer concrete, fly ash concrete, and limestone calcined clay cement (LC3).

Innovative composites, carbon-negative bricks, mycelium-based insulation, and engineered wood products (e.g., cross-laminated timber).

Lifecycle assessment (LCA) of low-carbon materials

To evaluate the sustainability of construction materials, lifecycle assessment (LCA) is employed. LCA considers the environmental impacts of a material throughout its life stages:

Raw material extraction, mining, logging, or harvesting of resources.

Manufacturing and processing, energy and emissions during material production.

Transportation, emissions from shipping and logistics.

Construction phase, material handling and installation impact.

Operational phase, energy consumption and performance over the building's life.

End-of-life, demolition, reuse, recycling, or disposal impacts.

Advantages of low-carbon materials

The adoption of low-carbon construction materials offers a multitude of benefits,

Reduced CO2 emissions, Geopolymer concrete and bio-based materials emit up to 80% less CO2 than traditional concrete.

Energy efficiency, manufacturing bio-based materials consumes significantly less energy compared to steel or concrete production.

Waste reduction, recycled materials reduce landfill usage and resource extraction.

Cost efficiency over time, despite higher initial costs, low-carbon materials often offer long-term savings through energy efficiency and durability.

Green certifications, use of sustainable materials helps achieve LEED, BREEAM, and WELL certifications, increasing property value.

Thermal insulation, materials like hempcrete and mycelium offer superior insulation properties, reducing heating and cooling costs.

Structural efficiency, engineered wood products like cross-laminated timber (CLT) provide strength comparable to concrete and steel.

Challenges and limitations

Despite their benefits, low-carbon materials face certain challenges,

Higher initial costs, innovative low-carbon materials can have higher upfront costs due to limited production scale.

Availability and sourcing issues, Bio-based and recycled materials are not always widely available.

Durability concerns, some low-carbon materials may have lower durability compared to traditional materials.

Lack of standardized regulations, variations in sustainability standards and certification processes hinder widespread adoption.

Innovative technologies are transforming low-carbon construction,

CCU technology captures CO2 emissions and injects them into concrete during curing, making the material carbon-negative.

Developed from industrial by-products and biochar, these bricks absorb CO2 from the atmosphere over time. Mycelium, a fungal network, offers biodegradable insulation with excellent thermal properties, reducing building energy consumption.

3D printing allows for efficient use of low-carbon concrete, reducing material waste and construction time.

Policy and regulatory landscape

Government policies and regulatory frameworks are crucial in promoting the use of low-carbon materials,

Carbon pricing and taxes, imposing taxes on carbon-intensive materials encourages the use of low-carbon alternatives.

Incentives and subsidies, financial incentives for builders using certified low-carbon materials.

Building codes and standards, Stringent embodied carbon regulations in the EU and California aim to reduce material-related emissions.

Dubbed the greenest commercial building in the world, it uses FSC-certified timber, reclaimed materials, and low-carbon concrete, achieving net-zero energy consumption.

This 7-story wooden office building is made entirely from cross-laminated timber (CLT), significantly reducing its carbon footprint compared to steel and concrete structures.

These eco-friendly residential towers incorporate vegetation as part of the building structure, absorbing CO2 and producing oxygen.

Conclusion

Low-carbon construction materials are key to mitigating the construction sector's environmental impact. While challenges remain in terms of cost and scalability, advancements in material science, coupled with regulatory support, are driving their widespread adoption. With increasing global emphasis on sustainability, the future of construction will inevitably rely on innovative, low-carbon materials that promote energy efficiency and reduce emissions.