Modal, or modal rayon fabric, was first developed in 1951 in Japan as an alternative to silk. This fabric is soft like silk but highly breathable and durable. However, some modal manufacturers still depend heavily on fossil fuels for energy and artificial chemicals. So we had to ask: How sustainable are modal fabrics?

Modal is generally a sustainable fabric, mainly because the raw materials come from renewable wood and the end product is durable and biodegradable. However, some modal manufacturing processes are associated with high usage of energy (often fossil fuels) and chemicals.

In this article, we’ll walk you through the life-cycle of modal fabrics used for clothes and bedding. Then, we evaluate its sustainability, potential, and shortfalls. And in the end, we’ll show you tips for buying sustainable products made with modal fabrics.

Here’s How We Assessed the Sustainability of Modal Fabrics

Modal is generally considered sustainable, mainly because this breathable fabric is durable and comes from renewable raw materials. However, not all modal fibers are made equally because some modal manufacturers still depend heavily on fossil fuels for energy while using and releasing a high amount of chemicals. 

“Sustainable: The ability to be maintained at a certain rate or level | Avoidance of the depletion of natural resources in order to maintain an ecological balance”

Oxford Dictionary

Modal is a type of semi-synthetic fabric, made with regenerated cellulose fibers extracted from wood.

These cellulose fibers in modal are obtained from the wood pulp of beech trees – tree species native to temperate and subtropical regions of the Northern Hemisphere. 

Modal fibers are classified as a type of rayon – a group of regenerated cellulose fibers:

• Viscose is considered the 1^st generation of rayon
• Modal is considered the 2^nd generation of rayon
• Lyocell is considered as the 3^rd generation of rayon 

All three generations (viscose, modal, and lyocell) are made with cellulosic fibers regenerated during manufacturing. They are similar to cotton or hemp in the sense that all of these fabrics contain cellulosic fibers, but the fibers in cotton and hemp are natural (instead of man-made). 

To understand the sustainability of modal fabrics, we must assess their life-cycle and each stage’s sustainability. This life-cycle assessment (LCA) is a method to evaluate the environmental impacts of products and materials. Over the years, companies have strategically used LCA to research and create more sustainable products. So, let’s have a look at the LCA of modal fabrics!

In this article, we’ll use the cradle-to-grave perspective of the LCA, examining the five stages of the life-cycle of clothes and bedding made with modal fabrics. When applicable, we also look at cradle-to-gate assessments. 

Overall, we can say that modal fabric is generally a sustainable material for clothing and bedding. However, the actual environmental impact of a particular product, like sportswear, depends on more specific factors, including the sourcing of the wood, manufacturing processes, and the distance and mode of transportation. 

Let’s dive deeper into each life-cycle stage and find out how you can buy modal fabrics more sustainably. 

How Sustainable Is the Sourcing Raw Materials for Modal Fabrics

The sourcing stage is generally sustainable as modal fabrics are made from renewable beechwood, obtainable from managed forests across North America and Europe. 

What Raw Materials Are Used for Modal Fabrics

Cellulose fibers from beechwood are the main material used for modal fabrics. 

(Synthetic chemicals are also used in making modal fabrics, but we will discuss those agents in the manufacturing stage.)

How Do the Raw Materials Sourced for Modal Fabrics Impact the Environment

The main raw materials used in modal fabrics come from the wood pulp of beech trees. These trees grow naturally in North America and Europe. Also, beech trees sequester carbon as they grow, indicating the sustainability of sourcing beech wood for modal’s raw material. 

• Carbon sequestration: As beech grow, they absorb CO₂ from the atmosphere while releasing oxygen. They act as a carbon sink, taking greenhouse gasses out of the atmosphere and helping to mitigate the climate crisis.

The carbon stored in wood (the raw material) is transferred to modal fiber, resulting in modal fiber, in some cases, being close to carbon neutrality (life-cycle carbon emitted is somewhat equal to carbon stored). For example, modal fibers made by Lenzing in their Austria facility have a 0.03 tonne CO₂ -eq per tonne fiber (cradle-to-factory gate). 

• Renewable material: In the US, there is a surplus of beechwood (i.e., the harvesting rate is lower the growth rate), meaning that it is relatively sustainable to cut down beech trees for wood. Beech trees are also found to thrive in abundance in higher temperatures and precipitation brought by climate changes. 

Where Are the Raw Materials for Modal Fabrics Usually Sourced From

Beech trees that provide the raw materials for modal fabrics grow natively in the US and Europe. They can be grown in sustainably-managed forests across temperate climates. It means that trees are cut down according to planned harvesting rotation, with new trees planted to replace them. Sourcing beechwood from, for example, PEFC or FSC-cerfifed forests as raw materials for modal is generally sustainable.

How Sustainable Is the Manufacturing of Modal Fabrics

Manufacturing modal fabric is energy and chemical intensive, which could have serious knock-on ecological impacts, especially if fossil fuels are the main energy sources at the manufacturing locations. However, integrated manufacturing processes can recover part of the energy during production while optimizing materials. 

How Sustainably Is Modal Fabrics Generally Manufactured

The typical modal manufacturing process follows these five steps: 

1. Prepare the beechwood pulp (harvesting wood, cutting it into penny-sized pieces, and grounding the pieces into a pulp)
2. Wood pulp is first dissolved in caustic soda, then depolymerized and reacted with carbon disulfide to form cellulose xanthate, which is dissolved in once more time caustic soda
3. Filter, degas, and age the modal solution 
4. Spin the solution in an sulfuric acid bath to regenerate the (modal) cellulose in threat-like form 
5. Wash, beach, finish, dry, and weave the yarn into modal fabric 

The modal manufacturing process is a modified version of the viscose process (the first generation of rayon. 

• However, a higher degree of polymerization leads to a strong, easy-to-way fabric with higher wet strength at the end.
• Also, modal manufacturing uses less chemicals compared to viscose manufacturing. The reduction of artificial chemical usage also means lower energy requirement and less toxic waste. 

Manufacturing Modal Fabrics Uses Artificial Chemicals

The modal manufacturing process requires a few different artificial chemicals, including: 

• caustic soda (or sodium hydroxide) 
• carbon disulfide 
• sulphuric acid 

Caustic soda, carbon disulfide, and sulphuric acid are all toxic chemicals that could potentially cause serious harm to the environment and workers.

Both caustic soda and sulphuric acid can damage the skin and eyes.

Carbon disulfide has been linked to higher levels of coronary heart disease, birth defects, skin conditions, and cancer, not in textile workers and residents in the vicinity of modal factories. 

In a closed-loop manufacturing process, these chemicals can be strictly controlled for recovering, reusing, and/or safely discharging. We will discuss this matter later in the Circular Economy section. 

Manufacturing Modal Fabrics Is Energy-Intensive 

The manufacturing process of modal fabrics is energy-intensive. A lot of energy is needed for wood and chemical production (input materials) and pulp and fiber production. 

For a tonne of modal fiber made by Lenzing, a leading modal manufacturer in Asia, the total energy usage is 78 GJ. 

This amount of manufacturing energy is equal to: 

• 75% of viscose (1^st generation of rayon) and lyocell (3^rdgeneration of rayon) made by the same company
• 142% of cotton fiber in the US and Canada. 

An Integrated Process Reduces Energy Usage in Manufacturing Modal Fabrics 

There are two production systems in manufacturing modal: integrated and separate processes:

• Integrated processes combine producing pulp and fiber at the same location, saving material and energy in the process. 
• Separate processes separate pulp production from fiber production, which adds transportation between the two facilities and loses out on the opportunities of recovering energy. 

In an integrated process, for example, in the Lenzing Modal Factory in Austria, production energy can be recovered and reused. Bark, thick liquor, and soda extraction liquor from pulp production become energy sources for pulp and fiber production. The remaining heat requirements – about 40% of the total heat requirements – come from incinerating externally purchased bark and municipal solid waste. 

Where Are Modal Fabrics Usually Manufactured

The top manufacturers in the modal fabric supply chain are located in: 

• China
• Pakistan
• India 
• Indonesia 
• Japan 
• Germany 
• Austria 
• The UK 
• The US

Energy Usage at Modal Manufacturing Locations

Because manufacturing modal fiber requires a lot of energy, the use of renewable energy (instead of fossil fuels) significantly reduces the carbon emission during the manufacturing stage (and, as a result, the whole life-cycle of modal fabrics). 

Different types of renewable energy are solar, wind, hydroelectric, geothermal, and biomass. 

Here’s the share of renewable energy (as a percentage of primary energy) for each of the main modal-producing countries as of 2021:

• China: 14.95% renewable energy
• Pakistan: 10.62% renewable energy
• India: 9.31% renewable energy
• Indonesia: 10.39% renewable energy
• Japan: 11.43% renewable energy
• Germany: 19.46% renewable energy
• Austria: 37.48% renewable energy 
• The UK: 17.95% renewable energy
• The US: 10.66% renewable energy

As you can see, the percentage of renewable energy varies significantly among modal manufacturing locations. This has a big implication on the environmental impact of the fabrics as the more fossil fuels (nonrenewable energy resources) are burned for heating, the higher the carbon emission of this manufacturing process (and, as a result, the whole life-cycle of modal). 

Waste Treatment At Modal Manufacturing Locations

Because of the high usage of (toxic) chemicals during manufacturing, waste treatment at modal facilities is a matter of concern, especially when factories in some countries lack transparency and regulations. 

For example, the Changing Markets Foundation reported in 2017 about fashion brands such as Zara, H&M, and Marks & Spencer and their links to highly polluting factories in China, India, and Indonesia, where they make viscose and modal fibers. (Because the manufacturing of modal is similar to viscose production, these two types of cellulose fibers are often produced on the same property.) 

The organization raised concerns about the devastating impact of wood pulp production on forests, people, and vulnerable animal populations.

In brief, it is important for you, as a consumer, to find out where the modal fabrics are made, not just where your clothes are sewn together.

How Sustainable Is the Transportation of Modal Fabrics

Transporting can be a carbon-intensive stage in the life-cycle of items made with modal fabrics because of the emissions associated with transporting and delivering vehicles. Modal fabrics typically travel from forests, where raw materials for modal are grown, to processing factories, then sorting centers, shops, and consumer’s houses before going to recycling centers or landfill. 

In the life-cycle of modal clothes, transportation typical occurs as below: 

• From forests where modal raw materials are grown to the modal fiber manufacturing locations
• From the modal fabrics manufacturing location to the clothing manufacturing location 
• From the clothing manufacturing location to sorting centers/physical shops 
• From sorting centers/physical shops to the consumer’s house 
• From the consumer’s house to the centers for recycling/ disposing

Traveling Distances of Modal Fabrics Vary 

It is uncommon for cellulose-based fabrics to have raw materials grown, processed, sewn, and sold in one town, country, or even continent. However, it is possible to source modal fabrics closer to home as the raw materials (aka beechwood) are available from Northern Hemisphere forests. 

Here are some scenarios of transporting modal fabrics: 

• Modal manufacturers can source beechwood grown in the US, have it processed into modal fabrics and clothing in a nearby factory, and then modal textile products around the US to sell to consumers.
• Others might ship beechwood from forests in Europe to factories in India and consumer markets in the US.
• Beechwood can be grown in China, transported to a factory in the immediate vicinity for dissolved pulp manufacturing, then to Germany for fiber manufacturing before being shipped worldwide to end users. 

You can reduce the transporting carbon footprint by opting for the modal fabrics from some of the closer temperate and subtropical forests (providing that they have not first been sent to a manufacturing factory on the other side of the world). 

The Carbon Footprint of Transporting Modal Fabrics Depends Largely on the Vehicle of Transportation 

During its life-cycle, a piece of modal clothing can be transported using various types of vehicles, including: 

• Large container ships 
• Planes 
• Freight trains 
• Long-distance trucks 
• Short-distance delivering vans 

And these various types of transportation vehicles have different carbon footprint impacts: 

• Large container ships are generally the most carbon-efficient option for international transportation of goods, while planes are the heaviest carbon emitter.
  Large container ships emit, per unit of weight and distance, half as much carbon dioxide as a train and one-fifth and one-fiftieth as much as a truck and a plane (respectively).
• Deliveries made by planes – for example, to fulfill fast shipping options for clothing – are the mode of transportation with the highest carbon footprint. 

For example, as a consumer, you can choose not to pick the fast delivery option when ordering modal clothes to reduce the carbon footprint of your modal items. 

How Sustainable Is the Usage of Modal Fabrics

The usage of modal fabrics is sustainable because modal clothing tends to last a long time while requiring few washes. 

Modal fabrics are soft and comfortable yet durable. Clothes made with this fabric will last years of wearing. Specifically, modal clothes can withstand more washes and dry cycles than cotton. 

Long-lasting clothing is generally more sustainable because you don’t need to replace it too frequently (thus, no need for more resources to make the new one). 

Another environmentally favorable property of modal fabric is its breathability: it generally doesn’t start smelling too quickly. 

Meaning that modal clothes can be washed less frequently, saving water and energy. 

How Sustainable Is the End-of-Life of Modal Fabrics

The end-of-life stage for modal fabric is generally sustainable because it is reusable, biodegradable, and compostable. 

Modal fabric is 100% cellulose, making it a biodegradable material. Thus, at the end of the fabric’s life, there are three available options: 

• Composting
• Incineration
• Landfill can all be used as end-of-life options. 

It takes about six weeks for modal products to decompose, contrary to plastic-based items that could take up space in the landfill for up to 100 years. Cotton typically takes 11 weeks to decompose. 

How Circular Are Products Made of Modal Fabrics

In the textile industry, a circular economy is designed to keep products and materials in use for as long as possible, especially through reusing and recycling. It also covers regenerating natural systems that support the industry and reducing polluted waste released into such systems.

“The circular economy is a systems solution framework that tackles global challenges like climate change, biodiversity loss, waste, and pollution.”

Ellen MacArthur Foundation

As a whole, the textile industry is almost linear: 97% of the input are new resource.

When it comes to modal fabrics, there have been incentives towards closed-loop manufacturing process. 

Since 2000, new technologies have emerged to produce modal fibers to keep harmful toxins from being released into the environment. Such closed-loop systems have excellent control to minimize the emission of gases to the environment and recover the solvent carbon disulfide up to 90-95%. Later technologies also improve the recovery of other resources (water and energy) used in manufacturing.

Lenzing^TM Modal is one example of a more sustainable modal fabric made in a closed-loop process. 

How Can You Buy Modal Fabrics More Sustainably

The key to sustainably buying modal products is to check on relevant environmental and original certifications. 

• Forest Stewardship Council: An FSC certification ensures that the wood comes from responsibly managed forests that provide environmental, social, and economic benefits.
• Program for Endorsement of Forest Certification: PEFC’s approaches to sustainable forest management are in line with protecting the forests globally and locally and making the certificate work for everyone. Getting a PEFC certification is strict enough to ensure the sustainable management of a forest is socially just, ecologically sound, and economically viable but attainable not only by big but small forest owners.
• USDA Certified Biobased Product: The USDA BioPreferred® Certification is a voluntary certification offered by the United States Department of Agriculture. The certification identify products made from plants or other renewable materials.
• STeP by OEKO-TEX®: STeP by OEKO-TEX® is an independent certification system for brands, retailers, and manufacturers from the textile and leather industry. It communicates organizational environmental measures, including reducing carbon footprint and water usage.
• Ecolabel: Ecolabel is the official European Union voluntary label recognized worldwide for certified products with a guaranteed, independently-verified low environmental impact. The label requires high environmental standards throughout the entire life-cycle: from raw material extraction through production and distribution to disposal. It also encourages companies to develop innovative, durable, easy-to-repair, and recyclable products.

Some certifications are signaling brands’ efforts toward lowered environmental impacts and a circular economy are: 

• B Corp Certification: The label B Corp is a certification reserved for for-profit companies. Certified holders are assessed on their social and environmental impacts. 
• Cradle2Cradle certification: Cradle2Cradle provides a standardized approach to material circularity. It assesses whether products have been suitably designed and made with the circular economy in mind covering five critical categories: material health, material reuse, renewable energy and carbon management, water stewardship, and social fairness.

Where to Buy Sustainable Modal Fabrics 

As we have established throughout the life-cycle assessment, not all modal clothes are made equally sustainable. 

Modal clothes can only be sustainable when the raw materials come from sustainably managed forests (where harvesting rotation allows new trees to grow and replace cut-down trees). In addition, the sustainability of modal fabrics depends on: 

• Energy usages (volume and source) in manufacturing 
• Chemical controls during manufacturing 

Consequently, you want to buy modal clothes from brands that are transparent about their raw materials and committed to reducing energy usage and emissions. Here are some of such sustainable brands (in alphabetic order): 

• Amour Vert
• Armedangels
• Casagin
• Muntagnard
• OhSevenDays
• TAMGA Designs
• The R Collective
• Threads 4 Thought
• TomboyX
• Whimsy + Row

Why Is It Important to Buy Products Made of More Sustainable Fabrics

It is important to buy products made of more sustainable fabrics because a sustainable textile industry has a lower carbon footprint, helps save natural resources, and is better for forests, animals, and humans. 

Buying Sustainable Fabrics Reduces Your Carbon Footprint 

The production of clothing and footwear is estimated to contribute 10% of global greenhouse gas emissions – more than all international flights and shipping combined. If the fashion industry were a country, it would be the fourth largest emitter of carbon dioxide. 

One way to reduce the carbon footprint of the clothes you buy is to opt for sustainable fabrics. Sustainable fabrics, which are often made with natural or recycled fibers, have relatively low carbon footprints compared to petroleum-based fabrics. For example, organic cotton made in the US has a carbon footprint of 2.35 kg CO₂ (per ton of spun fiber) – a quarter of polyester’s carbon footprint. 

Buying Sustainable Fabrics Reduces Demand For Natural Resources and Waste Management

The textile industry uses water and land to grow cotton and other fibers. It is estimated that 79 billion cubic meters of water were used for the sector worldwide in 2015. For example, producing a single cotton t-shirt requires as much water as one person drinks for 2.5 years (2,700 liters of fresh water).

Worse yet, the textile economy is vastly more linear than circular: the largest amount of resources used in clothes ended up in landfill (instead of being recycled to remake clothes). According to a report by the Ellen MacArthur Foundation,

• Less than 3% of materials used in the textile economy in 2015 came from recycled sources.
• In other words, more than 97% of resources used in making clothes are extracted new. 

When clothing items are disposed of within a short period of time – under a year in the case of half of the fast fashion clothes – the natural systems that provide raw materials for fabrics don’t have enough time to recover and regenerate, which could lead to ecological breakdown. 

Sustainable fabrics are made with less water and emissions while lasting longer:

• Because they are durable, you don’t need to buy new clothes too often. 
• Thus, you help reduce to pressure to extract more resources for making new items. 

Similarly, making and consuming sustainable fabrics made with recycled materials reduces the demand for virgin materials while helping tackle waste management. 

Buying Sustainable Fabrics Encourages Sustainable Management of Forests

Sustainable plant-based fabrics are made with raw materials from forests and plantations that are sustainably managed, such as complying with FSC standards. 

When you buy sustainable plant-based fabrics, you discourage unsustainable forestry practices like illegal logging. You can help reduce deforestation, biodiversity loss, and the effect of climate change. 

Buying Sustainable Fabrics Encourages Fairer Treatment of Animals 

The fashion industry is rife with animal mistreatment when it comes to making animal-based fabrics like cashmere or leather. Every year, billions of animals suffer and die for clothing and accessories.

Buying sustainable vegan alternatives can help to reduce the pressure on raising more and more animals to meet the demand for animal-based fabrics while sacrificing their well-being and lives. 

Suppose you have to buy fabrics made with, for example, leather or wool; make sure you only choose brands committed to cruelty-free products. In that case, you help advocate better treatments for animals raised within the textile industry. 

Using Sustainable Fabrics Encourages Fairer Treatment of Textile Workers 

Recent statistics from UNICEF estimated as many as 170 million child laborers worldwide, many of whom were engaged in some form of work in the textile industry. They don’t get paid minimum wages and often work long hours. 

When you buy sustainable fabrics from brands transparent about the working conditions at their factories, you discourage the use of child labor and help promote better working conditions for textile workers.

Final Thoughts

Modal fabric is generally a sustainable material. It is made with natural cellulose fibers and is fully biodegradable at the end of its life-cycle. Its modified manufacturing process is less energy and chemical-intensive than the first generation of rayon (viscose), making it a more sustainable option. 

Still, the usage of fossil-based chemicals makes it less sustainable than, for example, lyocell – the third generation of rayon, which uses organic substances. 

It is possible to find sustainable clothes made modal fabrics, with the raw materials for the yarns coming from sustainably managed forests and processed in closed-loop manufacturing systems. Besides, you want to check if your chosen brands are committed to reducing fossil-based energy and recycling fibers. 

To make it even more sustainable, buy second-hand modal clothes, use clothes for as long as possible, upcycle the material to extend its usage, and arrange for it to be recycled appropriately.

Stay impactful,

Sources

• SewPort: What is Modal Fabric: Properties, How its Made and Where
• Science Direct: Inorganic and Composite Fibers
• Impactful Ninja: How Sustainable Is Beechwood? Here Are the Facts
• ScienceDirect: Sustainable Fibres and Textiles
• Impactful Ninja: How Sustainable Is Viscose Fabrics? A Life-Cycle Analysis
• Impactful Ninja: How Sustainable Is Lyocell Fabrics? A Life-Cycle Analysis
• Science Direct: Life-cycle assessment (LCA)
• MIT SMR: Strategic Sustainability Uses of Life-Cycle Analysis
• Science Direct: Life-cycle assessment (LCA)
• MIT SMR: Strategic Sustainability Uses of Life-Cycle Analysis
• European Environment Agency: Cradle-to-Grave
• ScienceDirect: Life Cycle Assessment of man-made cellulose fibres
• AMERICAN HARDWOOD EXPORT COUNCIL: AMERICAN BEECH
• Britannica: Beech
• KLEIDERLY: Fabric series: All about Viscose
• CDC: CARBON DISULFIDE
• Lenzing: Home
• Impactful Ninja: What Is the Carbon Footprint of Renewable Energy? A Life-Cycle Assessment
• Impactful Ninja: What Is the Carbon Footprint of Solar Energy? A Life-Cycle Assessment
• Impactful Ninja: What Is the Carbon Footprint of Wind Energy? A Life-Cycle Assessment
• Impactful Ninja: What Is the Carbon Footprint of Hydropower Energy? A Life-Cycle Assessment
• Impactful Ninja: What Is the Carbon Footprint of Geothermal Energy? A Life-Cycle Assessment
• Impactful Ninja: What Is the Carbon Footprint of Biomass Energy? A Life-Cycle Assessment
• The World in Data: Renewable Energy
• Changing Market Foundation: Home
• Changing Market Foundation: Dirty Fashion
• Changing Market Foundation: Roadmap towards responsible viscose & modal fibre manufacturing
• Time for Change: CO₂ emissions for shipping of goods
• Good on You: Material Guide: What Is Modal? And Is It Sustainable?
• Tencel: Tencel^TM Modal
• Uniform Reuse: Fabrics Database – Modal
• SEMANTIC SCHOLAR: Biodegradation of Three Cellulosic Fabrics in Soil
• Ellen MacArthur Foundation: THE CIRCULAR ECONOMY IN DETAIL
• Ellen MacArthur Foundation: A New Textiles Economy
• Birlacellulose: Closed-Loop Technologies in Viscose Process
• Lenzing: Closing the loops
• Forest Stewardship Council
• Program for Endorsement of Forest Certification
• BioPreferred: WHAT IS THE BIOPREFERRED PROGRAM?
• OEKO-TEX: Certification according to STeP by OEKO-TEX®
• European Commission: EU Ecolabel
• B Corp Certification: Home
• C2CCertified: Home
• Amour Vert
• Armedangels
• Casagin
• OhSevenDays
• TAMGA Designs
• The R Collective
• Threads 4 Thought
• TomboyX
•  Whimsy + Row
• European Parliament: The impact of textile production and waste on the environment (infographic)
• Science Direct: The challenge of “Depeche Mode” in the fashion industry – Does the industry have the capacity to become sustainable through circular economic principles, a scoping review
• Science Direct: Carbon Footprint of Textile and Clothing Products
• European Parliament: Environmental impact of the textile and clothing industry
• European Parliament: What if fashion were good for the planet?
• Ellen MacArthur Foundation: A New Textiles Economy: Redesigning fashion’s future
• McKinsey: Style that’s sustainable: A new fast-fashion formula
• Our World in Data: Deforestation and Forest Loss
• Peta: Animals Used For Clothing
• The Guardian: Child labour in the fashion industry