Natural materials promise lower emissions and biodegradability, while synthetics offer unmatched durability — but which is truly more sustainable for building? Understand the real environmental impact of each to make smarter, greener choices.
By Evelyn Long, editor-in-chief of Renovated
The construction industry is responsible for much of the world’s carbon emissions, so the materials chosen to build homes and offices are more critical than before. As climate challenges grow urgent, architects are revisiting the building process, from design to demolition.
One key aspect they consider is the components used in construction. When looking at natural versus synthetic, most builders want to know which aligns most with a greener future. However, several factors come into play, making it worth looking into each one to make informed decisions.
The Basics of Natural vs. Synthetic Materials
Natural and synthetic building parts vary greatly when evaluating them for sustainability. While they are different in origin and processing, they also differ in how they impact the environment throughout their life cycle.
What Are Natural Building Materials?
Natural building materials are those sourced directly from nature with little to no industrial processing. Examples include timber, bamboo, straw, clay, wool and stone. Historically, people have used natural supplies for centuries, and these materials are resurging as sustainable design becomes a greater priority.
Renewability is one of their biggest advantages. For instance, bamboo is one of the fastest-growing and most renewable plants on the planet, as it can grow 50 centimeters to 8 inches a day. Additionally, many natural sources like wood and straw can sequester carbon, storing CO2 within the structure for decades.
Natural elements also tend to have lower embodied energy — the total energy required to extract, process and transport them. Studies show that straw-based walls have 50% less embodied energy and carbon emissions than masonry-built ones.
However, durability can vary. Without proper treatment, natural materials may be more vulnerable to moisture, pests or fire. That said, with modern construction techniques and protective finishes, builders can effectively address these vulnerabilities.
What Are Synthetic Building Materials?
Synthetic components are human-made, typically through chemical or mechanical processing. These include concrete, steel, plastic composites, vinyl, fiberglass and engineered wood. While they offer enhanced strength, they come with some environmental trade-offs.
Most synthetics come from non-renewable resources. Their production is typically energy-intensive — cement manufacturing alone is responsible for around 1.56 billion metric tons of carbon dioxide worldwide.
Regarding longevity, synthetic materials often outperform their natural counterparts. For example, lumber made from fibers, plastics and resin binders can last for decades with little maintenance. Their resistance to weather, pests and decay makes them popular in today’s construction projects.
However, this same resilience becomes a liability at the end of their life cycle. Many synthetics are non-biodegradable and difficult or costly to recycle, contributing to long-term waste and pollution.
Environmental Impact During Construction
Sustainability in construction begins the moment builders have raw materials extracted, processed and transported to the jobsite. The environmental impact of each type can vary widely, depending on where they come from and how manufacturers process them.
Natural Materials
Key factors that influence how natural materials affect the planet include the following.
1. Biodegradability
Wood, straw, wool and other components naturally decompose at the end of their life cycle, reducing landfill waste and long-term pollution.
2. Renewable Resources
Natural supplies come from forests, soil and crops. This makes them possible to replenish through responsible land management. Certifications like the Forest Stewardship Council (FSC) ensure ethical sourcing.
3. Reusability and Repurposing
Sources like reclaimed wood and natural stone are reusable in future projects with minimal reprocessing, giving them a second life and reducing resource extraction.
4. Lower Chemical Use During Installation
They typically require fewer synthetic adhesives, sealants or finishes, which reduces the release of harmful volatile organic compounds (VOCs). VOCs contribute to 75% of carbon emissions and respiratory issues, so less exposure is better for the planet and people.
Synthetic Materials
Synthetics often have a greater environmental impact in the following ways.
1. Non-biodegradability
Most synthetics do not break down naturally. They can persist in the environment for hundreds of years.
2. Microplastics and Particulate Pollution
Construction materials like fiberglass and plastic piping can shed microplastics during installation, potentially polluting local ecosystems and waterways.
3. Fossil Fuel Dependence
Production often relies on fossil fuels, contributing to greenhouse gas emissions before they arrive on a construction site.
4. Chemical-Intensive Finishes
Synthetic components frequently require treatments, such as fire retardants, water repellents and preservatives. Each can emit harmful substances during and after installation.
Longevity and Durability in Construction
How long a material lasts is crucial in sustainability. Its ability to withstand time, weather wear and environmental pressures can drastically influence a structure’s overall life cycle emissions and resource consumption. In this regard, natural and synthetic parts have strengths and drawbacks.
Natural stone, timber and clay have stood the test of time. Historic stone buildings and timber-framed houses can last for centuries with proper maintenance. However, organic materials are more prone to environmental conditions unless specially treated or protected.
For example, untreated wood will likely succumb to rot and termite damage, while straw bale construction requires weatherproofing plastering to increase usability. Despite these limitations, many natural elements age gracefully and gain aesthetic value when correctly sourced and installed.
On the other hand, synthetic materials can last several years to decades. For example, rubber slate roofing can resist degradation from weather conditions for around 50 years or more. However, synthetic durability can come at a cost. Some may degrade into harmful microplastics, become brittle under the sun or require energy-intensive maintenance if protective coatings fail.
Performance and Efficiency in Use
A factor in sustainability is how well it performs once it becomes part of a structure. In this phase, natural and synthetic materials offer unique benefits. However, they excel differently depending on the building’s needs, climate and design priorities.
Whether wool insulation or wood, natural materials offer breathability and can regulate indoor temperature and humidity. For instance, wool is a renewable insulator that filters indoor air by absorbing harmful substances.
However, synthetics are engineered for high efficiency and specialized performance. Polyisocyanurate foam and fiberglass batts are common in modern construction because they offer high R-values in thinner applications, which helps save space while maximizing insulation. Synthetic roofing membranes and vapor barriers also prevent moisture infiltration with minimal degradation over time.
In many cases, synthetic materials outperform natural ones in specific metrics, such as thermal retention in extreme climates or resistance to water damage. Yet, this often comes at the cost of increased embodied energy and reduced recyclability. Some builders address this by using hybrid systems, combining natural materials for structural purposes with synthetic elements to enhance sealing or insulation.
End-of-Life and Recyclability
A material’s sustainability continues through its disposal, reuse and repurposing. Truly eco-friendly components should leave as small a footprint as possible when no longer in use. This is where natural and synthetic often diverge dramatically.
Natural parts tend to have a clear advantage in end-of-life impact. Since they break down naturally, they are better for the environment. Many are also compostable or reusable. For instance, builders can salvage reclaimed timber for new builds with minimal processing. They can also return clay and adobe to the earth, while natural stone is reusable across multiple construction cycles.
However, synthetic materials do not biodegrade and may persist in landfills or the environment for years. Recycling is also a challenge. Many composites are nearly impossible to separate into recyclable parts. Additionally, some synthetic products can leach harmful chemicals into the soil when disposed of improperly. For instance, macroplastics are responsible for 88% of plastic leakage and often end up in freshwater sources.
Efforts to improve the recyclability of synthetic materials are increasing, especially through take-back programs and innovations. However, much of the world’s plastic has yet to land in the circular economy.
Sustainable Building Material Considerations
Choosing between natural and synthetic is more than a matter of picking one over the other — it involves weighing context, performance and long-term impact. Several key considerations can guide responsible material selection in sustainable construction.
1. Consider the Life Cycle Impact
It is essential to consider how a piece performs from cradle to grave, including raw material extraction, production emissions, transportation, installation, use and disposal or reuse. Life cycle assessment tools can help by comparing environmental impacts. Additionally, prioritizing materials with Environmental Product Declarations offers greater transparency into the life cycle.
2. Source Materials Locally When Possible
The farther the material has to travel, the greater its transportation-related carbon emissions. For instance, bamboo sources can be thousands of miles from their destination, making the carbon footprint increase substantially. Sourcing locally reduces the environmental footprint and often supports regional economies.
3. Prioritize Certified and Ethically Sourced Materials
Third-party certifications verify sustainable practices, fair labor conditions and responsible sourcing. For instance, Cradle to Cradle certification evaluates materials based on reuse potential, energy use, water stewardship and social fairness. Meanwhile, GREENGUARD labels minimize indoor air pollutants.
4. Factor in Climate and Building Use
Climate plays a huge role in performance. Some natural materials excel in dry, temperate zones but may struggle in high-humidity or flood-prone regions. Similarly, certain synthetic ones may be more suitable for commercial or industrial structures.
High thermal mass parts in hot climates can regulate indoor temperatures, whereas moisture-resistant materials may reduce maintenance and damage in coastal areas.
5. Think Beyond the Build
Opt for supplies that are easier than others to disassemble and reuse at the end of a building’s life. This supports a circular construction economy and significantly reduces waste.
Sustainability Is More Than a Label
There is no one-size-fits-all answer in the debate between natural and synthetic elements for sustainability. Natural materials offer biodegradability and a smaller environmental footprint, while synthetic options bring durability and innovative applications that support energy efficiency.
The most sustainable path forward lies in balance, selecting the right material for the job while considering full life cycle impact. As the construction industry grows, circular design principles and a deeper understanding of material trade-offs will be key to building better structures.