How Sustainable Are Sheep Wool Fabrics? A Life-Cycle Analysis

By
Quynh Nguyen

Read Time:25 Minutes

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Sheep wool is a wonderful natural material that can keep you warm in the winter and cool in the summer. But sheep farming is rife with practices harming animals, the lands, and ecosystems. So, we had to ask: How sustainable are sheep wool fabrics?

Conventional sheep wool is generally unsustainable, while recycled and/or organic sheep wool is often sustainable. The sustainability of sheep wool fabrics depends largely on how the sheep are raised. Sheep wool’s adverse impacts are global warming impact, land degradation, and biodiversity loss.

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

Here’s How We Assessed the Sustainability of Sheep Wool Fabrics

Sheep wool fabrics are made with the hair from a sheep fleece: a natural material that readily biodegrades at the end of its life. During the usage phase, sheep wool clothes and accessories can be washed sparsely, saving water and energy. Yet, some sheep farming systems are troublesome, affecting sheep wool fabrics’ sustainability and ethics.

“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

To understand the sustainability of sheep wool 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 sheep wool fabrics!

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

The life-cycle stages of sheep wool fabrics	Each stage’s sustainability
Sourcing of sheep wool fabrics	The raw material for sheep wool fabric comes from sheep fleece – the coat that a sheep wears during the winter. The environmental impacts of sourcing this material vary significantly depending on the sheep farms, with organic farming practices being the most sustainable. Sourcing wool fibers from discarded sheep wool waste is even more sustainable as it utilizes waste instead of putting strains on natural resources for raising additional sheep.
Manufacturing of sheep wool fabrics	Manufacturing sheep wool fabrics is energy and water-intensive, making sheep wool processing less sustainable. This process starts with collecting the fleece from a sheep. In many cases, the shearing is painful and stressful for the animal. The steps that come after fiber collection are mostly mechanical.
Transporting of sheep wool fabrics	Transporting can be a carbon-intensive stage in the life-cycle of clothing items made with sheep wool fabrics due to the distances covered and emissions associated with transporting vehicles. Sheep wool fabrics typically travel from pasture lands, where the fleeces are collected, to processing and finishing factories, sorting centers, shops, and consumer’s houses before going to recycling centers or landfills.
Usage of sheep wool fabrics	The usage of sheep wool is generally sustainable. Sheep wool fabrics require less frequent washes because they are breathable, odor-resistant, quick-to-dry materials.
End-of-life of sheep wool fabrics	The end-of-life stage for sheep wool is generally sustainable because untreated sheep wool is fully biodegradable and compostable.

Overall, we can say sheep wool fabrics are on a spectrum from unsustainable to sustainable, with conventional sheep wool being unsustainable and recycled and/or organic sheep wool often being the most sustainable.

However, the actual environmental impact of a particular product, like a sweater or a pair of gloves, depends on more specific factors, including the sourcing of the raw material (the fleeces from sheep), the manufacturing process, the transportation distance, and vehicles used during transport.

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

How Sustainable Is the Sourcing of Raw Materials for Sheep Wool Fabrics

The raw material for sheep wool fabric comes from sheep fleece – the coat that a sheep wears during the winter. The environmental impacts of sourcing this material vary significantly depending on the sheep farms, with organic farming practices being the most sustainable.

Sourcing wool fibers from discarded sheep wool waste is even more sustainable as it utilizes waste instead of putting strains on natural resources for raising additional sheep.

What Raw Materials Are Used for Sheep Wool Fabrics

Sheep wool is made with wool fibers from the winter coat of a sheep. In wild sheep, the extra hair is naturally shed as soon as the weather gets warmer. However, this hairy coat is obtained by shearing the domesticated sheep raised on farms.

There are many sheep breeds whose hair varies in length, thickness, or crimp (the natural waviness).

Breeds like merino sheep, which gives us merino wool, tend to have the softest and finest hair.
Other fine hair sheep breeds are Rambouillet and American Cormo.
The fleece from breeds like Wensleydale or Karakul could be coarser.

How Do the Raw Materials Sourced for Sheep Wool Fabrics Impact the Environment

Sheep wool fabrics are made with sheep’s winter coats, which, generally considered, come from a renewable resource. However, this raw material bears the environmental impacts of farming sheep, including global warming, land contamination and degradation, and biodiversity loss.

Sheep Wool Fibers Can Be Considered A Renewable Resource

A sheep can produce a significant amount of fibers per fleece and repeated harvest throughout its relatively long lifespan.

The fleece of a sheep can be ready for collection every few months. For example, farmers can shear sheep of certain breeds as frequently as 2 to 3 months.
On average, each sheep yields about 10 lbs of wool a year, enough for about 6 sweaters.
A sheep lives from 10 to 12 years. And in the case of merino sheep, will be able to produce enough wool for over 100 garments containing around 1 lb each. (Note that merino sheep breeds tend to have a higher fiber yield.)

It’s noteworthy that the renewability of fibers from sheep fleece is also thanks to their population: There are about 1.2 billion sheep worldwide, spreading over upland habitats on all continents.

Sheep Farming Emits Methane – A Potent Greenhouse Gas

Sheep wool fabrics’ sourcing stage (aka the sheep farming) has a high global warming potential, generally many times higher than other textile materials made with plant fibers. The reason is the sheep and their way of digesting food:

Sheep, and other ruminant animals, belch enteric methane (CH₄) as they digest their food.
Methane is the second most significant contributor to the climate crisis, following carbon dioxide. It traps more heat than carbon dioxide, so it is considered a more potent greenhouse gas, especially in the immediate future.
Methane is 84 times more potent than carbon dioxide over a period of 20 years.
On a 100-year timescale, methane has 28 times greater global warming potential than carbon dioxide.

For example, a knitted jumper made with 12 ounces of Australian wool has a sourcing carbon footprint 27 times higher than that of a knitted jumper made with Australian cotton fibers.

In absolute value, the farming stage of (Australian) wool fabrics has a carbon footprint of 24.9 kg CO₂ -eq per kilogram unit of greasy wool at the farm gate, according to a life-cycle assessment. Direct emission of methane from the sheep accounts for a significant share (86%) of all GHG emissions of the farming stage. Other emission sources include animal wastes and fertilizer inputs.

Some researchers also look into the way pasture lands sequester carbon in the soil and vegetation. They suggest that the amount of carbon sequestered could be deducted from the total emissions over the full life-cycle. (The deduction is equivalent to 4% for each successive wool production year over 100 years.)

Land Occupation of Sheep Farming Could Have Serious Ecological Consequences

Raising sheep takes up a lot of land.

For example, considering the stocking rate in Australia, 109 acres (44.04 hectares) of land are needed to raise the sheep to get enough wool fibers for one bale. That is 367 times more land than would be required for a bale of cotton – a plant fiber.

However, Australia has a relatively low stocking rate compared with northern hemisphere countries or other wool-producing nations such as New Zealand. Thus, sheep farming in Australia requires more land per animal in absolute numbers.

On the other hand, a low density of sheep reduces the risk of overgrazing, which could lead to pasture lands not being able to recover, degraded and eroded, and biodiversity loss.

It is important to note that not all lands are equal regarding the ecological consequences of using the land. For example, pastures set up on non-arable grounds, which are not suitable for growing crops, are different from pastures obtained through clearing bio-diverse forests.

Sheep Farming Contaminates The Grounds and Waterways

With the increasingly large sheep flocks, excessive amounts of manure and other toxins enter the ground, degrading soil quality and contaminating waterways. This contributes to problems like eutrophication.

Also, the toxic chemical “sheep dip,” used to kill parasites, often overflows into the surrounding water bodies and grounds.

According to a life-cycle assessment using the Ecoinvent database, the shares of the sourcing stage (or sheep farming) are significant in several impact categories from cradle to factory gate. Specifically,

Sheep farming accounts for around 85% of the total climate change impact
Rearing sheep causes almost all human toxicity up to the point when finished wool products leave the processing factory
The share of sheep farming in the freshwater ecotoxicity impact is around 95%
Sheep farming also accounts for about 80% of the total freshwater eutrophication impact

It is important to note that the above-mentioned adverse environmental impacts often come from worst-case scenarios for sheep farming: high density of sheep on pasture lands, overgrazing, and failure to properly handle the agricultural waste. However, some farming practices don’t damage the land but help restore it, from which sheep wool can be sourced sustainably.

For example, regenerative farming practices could improve soil health (instead of degrading the ground), resulting in more carbon sequestration. Some examples of these agricultural practices that sheep farmers can do are as followings:

Planting native trees in pasture lands
Confining flocks to specific areas and letting the grass and other plants regrow in other parts of the land before the sheep graze there again. This practice is called rotational grazing.
Composting of sheep manure to sequester carbon
Growing crops in pastures to improve biodiversity and soil health
Removing pollutants from waterways

According to a life-cycle assessment comparing the carbon footprint of garments produced in various farming systems, good land management helps increase carbon sequestration. Consequently, garments made with fibers produced on land well-managed have lower carbon footprints (cradle to grave). When all other elements are similar, the difference between good land management and conventional land management is a 60% decrease in carbon footprint.

Where Are the Raw Materials for Sheep Wool Fabrics Usually Sourced From

The wool industry produces around 1,949 million kg (2021) of raw wool from a global flock of approximately 1.2 billion sheep.

The top producers of wool fibers are Australia, China, and New Zealand. Australia is the world’s most important sheep-rearing nation and home to more than 71 million sheep.

Because of the methane sheep belch as they eat, sheep production results in high emissions of greenhouse gas. The GHG emissions from all Australian sheep are equivalent to burning fossil fuels to supply energy for one-million homes for a whole year.

Another issue with sheep farming is land degradation and desertification caused by overgrazing. In several sheep-rearing countries, many areas are so degraded that the grounds can no longer be productive.

For example, the Patagonia region of Argentina was once incredibly rich in species and now contains stretched-out deserts empty of life, all because of sheep ranching. In the area, roughly 20m acres have become so deteriorated that they are abandoned.

Wildlife also suffered from desertification and expanded sheep flocks.

The Australian native Tasmanian tigers were blamed for sheep deaths and, consequently, brought to extinction by the wool industry.
Dingoes, another species native to Australia, are often poisoned, trapped, and shot by the wool industry.
Coyotes and kangaroos are routinely killed by sheep breeders.

How Sustainable Is the Manufacturing of Sheep Wool Fabrics

Manufacturing sheep wool fabrics is energy and water-intensive, making sheep wool processing less sustainable. This process starts with collecting the fleece from a sheep. In many cases, the shearing is painful and stressful for the animal. The steps that come after fiber collection are mostly mechanical.

How Sustainably Are Wool Fabrics Generally Manufactured

Here are the standard steps in manufacturing sheep wool fabrics:

Collecting the fibers from the sheep: This can be done by shearing the whole fleece of the animal. Depending on the breed and the farm practices, shearing could happen once or multiple times a year.
Scouring: The raw fibers (“greasy” sheep wool) are cleaned to remove dirt, impurities, and other organic matter. Lanolin oil, secreted from the young sheep’s skin, makes wool greasy. Most large producers of sheep wool use chemical catalysts to remove lanolin from the hair, though there are other ways.
Carding: Sheep wool fibers are sorted into grades and combed into long, thin strings.
Spinning: The carded fibers are fed into a spinning machine, which twists the sheep wool fibers to form yarn.
Weaving or knitting: The sheep wool yarn is (plain- or twill-) woven or knitted into fabric.
Finishing and post-treatment: The fabric is occasionally dyed and subject to chemical treatments. Some post-production finishing treatments include:
- Fulling: a process in which the wool fabrics are immersed in water to make the fibers interlock
- Crabbing: a process that permanently sets this interlocking of fibers
- Shrinking-proofing

The manufacturing process of sheep wool fabrics is relatively standard for textiles made with natural fibers. In most cases, sheep wool manufacturing doesn’t involve toxic synthetic chemicals. However, mechanical processes require energy and water resources.

Sheep Wool Manufacturing Is Energy-Intensive

Energy is needed to heat water for cleaning and to produce the electricity needed to run machinery (spinning, weaving, or knitting). And if fossil fuels are the main source of electricity, it will increase the manufacturing carbon footprint.

For example, according to a life-cycle assessment of a sweater made with wool from merino sheep, manufacturing accounts for 47.7% of fossil fuel use and 23.5% of greenhouse gas emissions across the whole value chain (cradle-to-grave).

A change to renewable energy will reduce the carbon footprint of this step. Organic waste from wastewater treatment during the scouring processes could be one source of generating renewable energy.

Sheep Wool Manufacturing Causes Wastewater Pollution

Scouring and dyeing are the key processes causing wastewater pollution.

The scouring removes grease, pesticides, and other organic matter (including feces) from the fleece of the sheep. To wash and clean the sheep wool, potent cleaning agents and a large quantity of water (which needs heating up to 150^oF to melt to wool wax or grease).

Chemicals and organic matter may become suspended in the wastewater after scouring. If not treated properly, they contaminate the freshwater supply. One study found that the average wastewater from wool scouring contains as much as 291 times more pollutants than fresh (or blue) water.

Also, the dyeing process can contaminate surface water with heavy metals like chrome. Using natural dyes will avoid this contamination though these expensive dyes aren’t always opted for by sheep wool fabric producers.

Where Are Sheep Wool Fabrics Usually Manufactured

Australia is the world’s leading exporter of sheep wool fibers, but the processing of these fibers occurs predominantly in China due to lower labor cost.

The world’s top 10 producers of wool textile, including sheep wool variety, are:

China
Australia
New Zealand
Turkey
United Kingdom and Northern Ireland
Morocco
Iran
Russia
South Africa
India

Let’s look into the sustainable and ethical issues associated with these countries’ sheep wool fabrics production.

Animal Cruelty Is Widespread At Sheep Farms

The ethics of using sheep wool is tainted with the widespread mistreatment of the sheep.

Sheep have been increasingly bred to maximize the amount of wool they carry. Merino breeds, for example, are engineered for wrinkly skin to increase the surface area for hair. This unnatural overload of wool causes many sheep to collapse and even die of heat exhaustion during hot months.

While carrying a thicker coat of hair, sheep are at a higher risk of flystrike – a condition in which maggots eat the sheep alive. The area under the tail is extremely vulnerable for flies to lay eggs, which turn into larvae.

To deal with flystrike, some farmers perform a procedure called “mulesing,” in which they remove the wooly skin near the buttocks of a sheep.

Mulesing is an extremely painful procedure for sheep, especially when it is often done without painkillers.
The cruel practice of “mulesing” is banned in New Zealand, yet still available in Australia – home to the world’s largest flocks of sheep.
Flystrike can be avoided thanks to regular checking, shearing around the buttocks of a sheep, and other interventions. However, these practices take time and are not feasible (or profitable) with a very large flock of sheep.

Other mistreatments of sheep include:

Castrating
‘Tail docking’ (chopping off a sheep’s tail)
Kicking, punching, swearing aiming at the sheep while shearing the fleece
Sewing up cuts caused by shearing without painkillers

Even though the natural lifespan of sheep is around 10 to 12 years, many sheep are killed when they reach 5 or 6 years old because they no longer produce high-quality fibers.

Moreover, many sheep are left to die at their lamb stage due to the wool industry selectively breeding for twins and triplets to quickly increase the flock size.

Twins and triplets are more likely to be smaller, weaker, and unable to withstand the harsh conditions they are born into.
It is also much more difficult for the ewes to feed twins and triplets.
Sheep are increasingly bred for lambing in the winter (instead of spring as nature dictates). Winter-born lambs are more cost-effective because the lambs can be fattened up quickly with green grass in the spring. However, winter-born lambs have to face much harsher conditions. Furthermore, smaller twins or triplets are more vulnerable to death from exposure to the cold.

GHG Emissions During Manufacturing Wool Fabrics Vary Depending on Location

Because wool fabrics production is energy-intensive, using renewable energy (solar, wind, hydroelectric, geothermal, and biomass) would significantly reduce carbon emissions at this stage.

According to Our World in Data, the shares of renewable energy in primary energy in wool-producing nations vary significantly. The difference between the wool-producing country with the highest percentage of renewable energy (New Zealand) and the wool-producing country with the lowest share of renewable energy (Iran) is a staggering 31 times.

Specifically, renewable energy shares in the top 10 wool producers are as followings:

China: 14.95% renewable energy
Australia: 12.93% renewable energy
New Zealand: 40.22% renewable energy
Turkey: 16.52% renewable energy
United Kingdom and Northern Ireland: 17.95% renewable energy
Morocco: 7.64% renewable energy
Iran: 1.29% renewable energy
Russia: 6.62% renewable energy
South Africa: 3.41% renewable energy
India: 9.31% renewable energy

The production of sheep wool fabrics, including fiber production at the farm level and textile processing at the factory level, accumulates high environmental impacts in many categories. Up to the factory gate, sheep wool fabrics are high-impact materials.

Conventional sheep wool is ranked class E – the least sustainable fiber class by Made-By Environmental Benchmark for Fibres.

However, this benchmark doesn’t consider wool’s usage phase and end-of-life options, which are much more environmentally favorable (as we will explain later) than many other textile materials. Also, the benchmark doesn’t cover organic and recycled wool fabrics.

How Sustainable Is the Transportation of Sheep Wool Fabrics

Transporting can be a carbon-intensive stage in the life-cycle of clothing items made with sheep wool fabrics due to the distances covered and emissions associated with transporting vehicles. Sheep wool fabrics typically travel from pasture lands, where the fleeces are collected, to processing and finishing factories, sorting centers, shops, and consumer’s houses before going to recycling centers or landfills.

In the life-cycle of sheep wool clothing items, transportation typically occurs as below:

From grasslands, where the sheep’s fleeces are collected, to yarn factories
From yarn factories to textile manufacturers
From textile manufacturers 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 of

Traveling Distances of Sheep Wool Fabrics Vary Depending on the Supply Chain

It is not uncommon for sheep wool fabrics to have their supply chain spreading globally, meaning that animal farming, yarn processing and finishing might happen in various towns, countries, or even continents.

Here are some scenarios for transporting sheep wool fabrics:

Sheep wool manufacturers can source the fleeces from New Zealand, ship them to China to be scoured, Vietnam to be spun, Cambodia for garment-making, and finally across the Pacific for US consumers.
The fleeces are collected from sheep in Argentina and processed in the US before selling to consumers worldwide.
Sheep wool manufacturers source fibers in the UK and turn them into sheep wool products in Italy, which are sold mainly in Europe and North America.

You can reduce the transporting carbon footprint by choosing sheep wool fabrics that travel shorter distances.

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

During its life-cycle, a piece of sheep wool 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 sheep wool clothing items and accessories to reduce the carbon footprint of your order.

According to a life-cycle assessment of a sweater made with wool from merino sheep, the shares of transportation in several impact categories across the whole value chain (cradle-to-grave) are as followings:

Transportation accounts for 12.6% of the total fossil fuel requirement
Transportation accounts for 5.2% of the total global warming impact
Transportation accounts for 3.6 % of the total freshwater usage

How Sustainable Is the Usage of Sheep Wool Fabrics

The usage of sheep wool is generally sustainable. Sheep wool fabrics require less frequent washes because they are breathable, odor-resistant, quick-to-dry materials.

The usage phase is a main source of energy consumption in the life cycle of clothing, due to washing, drying and ironing. Compared to many other textile materials, using wool fabrics, including the sheep wool variety, would be more sustainable because of the less frequent need for washing, low washing temperature requirements and suitability for air drying practices.

Sheep wool fabrics are odor-resistance. Thus, sheep wool clothing requires fewer washes than many other textile materials. Typically, woolen socks can be worn 2.5 times per wash and woolen sweaters can be worn 10 times per wash. In comparison, cotton socks and cotton sweaters are generally washed after 1,5 and 5 wears, respectively.
Washing instructions for sheep wool clothes often ask for 30°C instead of 40°C or higher. Low-temperature washes use less energy.
Sheep wool fabrics should be left to dry on the line because the mechanical friction of a tumble dryer is not good for the fibers. This property helps further reduce energy requirements, either for running drying appliances or heating the drying space.

As a consumer, you can reduce the environmental impact of your usage by maximizing the number of wears between washes, avoid unnecessary hot washes or machining drying. You can avoid full washing with airing and spot-cleaning sheep wool garments.

Also, the longer you use a piece of clothing, the lesser the environmental impact of each wear.

Wool garments thrown out after only 15 wears were responsible for nearly six times the amount of pollution than garments with just over 100 lifetime wears.
On top of that, if the garment lifetime were to increase to 400 lifetime wears, it would reduce total emissions by 49 – 68%.

According to a life-cycle assessment of a sweater made with wool from merino sheep, the use phase was a significant contributor to its environmental impacts. The shares of this usage stage in several impact categories across the whole value chain (cradle-to-grave) are as followings:

Usage accounts for 30.4% of the total fossil fuel requirement
Usage accounts for 13.4% of the total global warming impact
Usage accounts for 37.1 % of the total freshwater usage

How Sustainable Is the End-of-Life of Sheep Wool Fabrics

The end-of-life stage for sheep wool is generally sustainable because untreated sheep wool is fully biodegradable and compostable.

As a natural textile material, sheep wool can be left to degrade naturally in a landfill or be composted. Decomposing time depends on many environmental factors and if the fabrics are treated and blended.

For example, according to a study by researchers in New Zealand, when burial in soil, fabrics made with fibers from merino sheep degrade quickly:

After two months, wool fabrics would lose around 36% of their mass
After nine months, wool fabrics would almost completely degrade (99% of their mass).

In comparison, a polyester knitted fabric did not degrade at all after the nine-month burial period.

The hair from sheep is made up of keratin – the same protein in human hair. Bacteria and fungi break down this protein and return essential plant nutrients, including nitrogen, magnesium, and sulfur, back into the soil. Thus, wool makes a great garden compost.

Sheep wool has also been found to readily biodegrade in a marine environment, whereas synthetic fibers do not.

A study comparing the biodegradability rate of untreated and machine-washable sheep wool with nylon, polyester, and polypropylene in a marine environment pointed out the outstanding rate at which wool degrades.

Following are the specific rate of biodegradability for all four materials:

Sheep wool: 67.3%
Polyester: 6.3%
Polypropylene: 1.8%
Nylon: 0.8%

It is important to note that sheep wool is sometimes blended with other materials for durability and performance. Mixing materials would normally hinder biodegradability and the opportunities for recycling.

How Circular Are Products Made of Sheep Wool 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 is new resource.

Specifically, recycling wool reduces the drain on natural resources, leading to stabilized flock numbers, diminishing methane emissions, and lessening the grazing pressure on pasture lands so they can regenerate.

Wool is the most reused and recyclable fiber in all textile materials, according to Woolmark. Still, the rate of recycling wool is lower than it used to be and what the industry is capable of.

There are three established ways of recycling wool:

The closed loop system: a mechanical process that returns garments to the raw fiber state and turns the fiber into yarn again to produce recycled wool clothes. The new fabrics can be woven or nonwoven (like Cloudwool).
The open loop system: the wool from a previous product is used (mostly as it is) for a new product, such as insulation or mattress padding.
Re-engineering: to make a new product from a used woolen product like a jacket.

There are also emerging chemical recycling systems, though these systems, unlike the three above-described ones, require expanding new technology.

How Can You Buy Sheep Wool Fabrics More Sustainably

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

Global Organic Textile Standard (GOTS): A globally-recognized certification system that ensures a certain threshold of organic content has been met. It covers manufacturing, packaging, labeling, transportation, and distribution (but not what happens in the grasslands where sheeps are raised).
The Responsible Wool Standard (RWS): An all-encompassing wool certification that ensures all facilities and aspects of Merino production are held to the highest standards. It covers everything from farms, top makers, spinners, fabric mills, garment makers, and even the retailers themselves.
Woolmark Certification: Woolmark certification is for wool products that were made using sustainable and cruelty-free methods.
ZQ Merino: This certification system focuses on the quality, sustainability, and ethics of Wool from farm to fashion. They have five core principles they abide by in each step of the wool process: Animal Welfare, Environmental Sustainability, Quality Fiber, Traceable to Source, and Social Responsibility
Recycled Claim Standard (RCS): The Textile Exchange RCS was originally developed as an international, voluntary standard that sets requirements for third-party certification of Recycled input and chain of custody. (For recycled sheep wool fabrics)
The Global Recycled Standard (GRS): The Global Recycled Standard (GRS) is an international, voluntary, full product standard that sets requirements for third-party certification of Recycled Content, chain of custody, social and environmental practices, and chemical restrictions. It can be used for any product with more than 20% recycled material.(For recycled sheep wool fabrics)
Certified Organic Wool: Wool produced following federal standards for organic livestock production as described in the U.S. Department of Agriculture’s National Organic Standards. (For organic sheep wool fabrics)
Certified Animal Welfare Approved: A Greener World (AGW) has the most rigorous standards for farm animal welfare and environmental sustainability across the globe. AGW’s Certified Animal Welfare Approved standards have been developed in collaboration with scientists, veterinarians, researchers, and farmers around the world to maximize practicable, high-welfare farm management with the environment in mind.
IWTO Specifications for Wool Sheep Welfare: Specifications developed by the wool-growing country members of IWTO.

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 Sheep Wool Fabrics

We have established throughout the life-cycle assessment that sheep wool fabrics are on a spectrum from unsustainable to sustainable. Unsustainable sheep wool fabrics are associated with farming systems promoting overgrazing, land degradation, and biodiversity loss.

However, some sheep wool producers and clothing manufacturers address the above challenges in their sourcing and production and/or opt for recycling materials instead of putting strain on natural resources and organic farming to reduce pollution. Here, we compile for you a list of such sustainable brands selling recycled and/or organic sheep wool fabrics (in alphabetic order):

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 newly extracted.

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 the 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 sheep or goat wool. 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, sheep wool 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 labors 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

Sheep wool fabrics are on a spectrum from unsustainable to sustainable, largely depending on the farming systems in which sheep are raised for their fleece.

Sheep wool fabrics are generally made from renewable resources. They are breathable and odor-resistant, leading to a low-impact usage phase. At the end of their life, they are readily biodegradable and suitable for composting.

Also, it is possible to produce sheep wool sustainably and ethically, with controlled grazing, high considerations for the sheep, and less fossil fuel dependency.

To make it even more sustainable:

Buy second-hand, recycled, or upcycled sheep wool clothing items and accessories.
While using sheep wool products, maximize the number of wear between washes, and keep the items as long as possible.
At the end of sheep wool products, upcycle the material to extend its usage, and arrange for it to be recycled or properly disposed of.