The Essential Guide to Semi-Synthetic Fabrics

In recent years we’ve seen a growing appetite for more sustainable fabric options that are less harmful to the environment in their production. You may have heard of fabrics made from Tencel, modal, bamboo or Ecovero viscose but aren’t sure of the differences and similarities between them all, or what projects they’re best suited to. In this blog I’ll talk you through these different fabrics, how they’re made, what they feel like and how to work with them.

You can hear me chat about these fabrics and show lots of examples in my Youtube video below, or read on for written notes and links to fabric and pattern combinations using these types of fabrics.

Key Points

These fabrics are known as semi-synthetic as they are produced using natural fibres (e.g. from trees or bamboo plants) but require extraction and processing before they can be spun into thread. They’re very similar to viscose and rayon but their production methods can make them more environmentally friendly alternatives to these fabrics, as viscose and rayon have quite intensive production techniques.

You might sometimes see that these fabrics have the STANDARD 100 by OEKO-TEX® certification. This is one of the world's best-known labels for textiles that are tested independently to ensure that they don't contain any harmful substances and are therefore harmless for human health. You can find out more information on this certification by visiting the Oeko Tex® website in this link.

These fibres can be made into lots of different types of fabric, both woven and jersey (knitted). We’ll discuss below the most common types and what you’re likely to find when you’re fabric shopping.

Tencel

How is it made?

Tencel refers to the brand name Tencel™, of Austrian company Lenzing AG. Tencel produces a wide range of fabrics but is most well known for its fabrics made from lyocell fibres. As a result, Tencel and lyocell are often used interchangeably, similarly to how Hoover and vacuum are used interchangeably here in the UK. I’ve used the name Tencel in this blog as this is how it’s so often referred to, but when used like this Tencel usually refers to lyocell fibres produced under the Tencel™ brand name. You can find out more about Tencel™ Lyocell in this link.

Tencel fibres are often produced from sustainably grown eucalyptus trees, which are quick-growing and need minimal pesticides. The fibres are extracted using a unique closed loop system which recovers and reuses the solvents used, minimising the environmental impact of production when compared to traditional viscose production methods. Less energy and water are also used in production.

Tencel fibres can be made into woven and knitted fabrics, though they’re most frequently seen in woven fabrics. Common versions you’ll probably see are plain woven, twill weaves with their classic diagonal texture and crepes, which have a slightly crinkled texture due to the twisted threads.

What does it feel like?

Fabrics made from Tencel lyocell fibres behave in a similar way to viscose and rayon fabrics. They have a silky drape, are breathable and feel comfortable to wear. Tencel fabrics are durable with good colour retention and tend to have a slight sheen or lustre to them. Tencel lyocell is also a very absorbent fabric, being 50% more absorbent than cotton.

Tencel tends to be a bit more expensive than equivalent fabrics and you might sometimes see it blended with other fibres - this can add to its characteristics, making it more hard-wearing for example, but can also make it more affordable.

Example garments

Pictured below from left to right is the Hey June Handmade Amherst Shirt made using a lightweight 100% Tencel Denim in a dark and light colourway and the True Bias Zoey Top made using a Tencel ribbed jersey.

Modal

How is it made?

Modal fabrics are also produced in a similar manner to viscose and Tencel Lyocell fabrics, with the extraction of cellulose fibres - in this case from beech trees. These are then treated before they can be turned into a weaveable fibre. Modal is not inherently environmentally-friendly, but the production techniques used can make it a sustainable option. For example, those used by Lenzing who produce Tencel™ Modal.

Modal fibres can be woven and when you might see them described as modal viscose. You’ll frequently see them used in knitted fabrics as well. They blend well with other fibres, so you might find they’re blended with elastane or cotton to create French Terry fabrics, ribbed fabrics or single jerseys.

What does it feel like?

Fabrics made from modal fibres behave in a similar way to viscose and rayon fabrics, both woven and knitted types. They have a good drape, are breathable and feel comfortable to wear. It is not as durable as tencel lyocell, but is softer and smoother to the touch. Modal is also a very absorbent fabric and it does not build up static. It is not as quick drying as tencel, though it tends to be more affordable.

When used in fabrics such as loop-back French Terrys they increase the drapiness of the fabric, meaning a French Terry with modal in it would have a greater drape to it than a cotton version.

You may also come across micro modal, which uses a very fine version of this fibre to make an even softer fabric.

Example garments

Pictured below from left to right is the Closet Core Sallie Jumpsuit made using a Tencel Modal light weight jersey fabric, the Grainline Linden Sweater and the Megan Nielsen Virginia Leggings both made using Loopback modal Jersey.

Ecovero Viscose

How is it made?

Ecovero Viscose is a very similar fabric to the traditional viscoses you may be used to working with, but the way it is produced is very different. Lenzing Ecovero Viscose fibres are derived from sustainable wood and pulp, coming from certified and controlled sources.

These viscose fabrics are free of harmful substances and the manufacturing cycle has been optimised to drastically reduce the environmental impact compared to traditional viscose. Emissions and water impact are up to 50% lower using these production techniques. Lenzing also state that their wood sourcing policies are audited annually for their contribution to forest conservation, transparency, and commitment to sustainability.

Like traditional viscose, you’ll find Ecovero viscose in both woven and knitted forms. There’s lightweight challis, heavier twills and crinkly crepes, alongside stretchy jerseys. You can read more about Ecovero Viscose in this link.

What does it feel like?

Just like generic viscose fabrics, those made of Ecovero viscose have the same great qualities. They’re very drapey, soft to the touch and comfortable to wear. They’re also breathable and don’t tend to build up static. They do have a bit of a tendency to crease, so just make sure you have your iron handy!

Bamboo

How is it made?

Bamboo fabrics are produced from the fibres of the bamboo plant, which is the fastest growing grass species in the world. Bamboo grows easily without much need for pesticides and fertilisers (as anyone who’s grown any in their garden will know!). Because of this, bamboo has become a popular choice for fabric producers. It can be grown in difficult areas (such as hillsides) and uses much less land and water than cotton.

There are a variety of methods for turning raw bamboo into fibres that can be woven into fabric, which have varying environmental impacts. It can be processed using a closed loop method similar to Tencel lyocell fibres or it can be mechanically extracted, a method which can be used to produce organic bamboo fabrics. It can also be processed using techniques generally used in the production of traditional viscose, which unfortunately can be more harmful to the environment and causes the fabric to lose many of its beneficial properties.

Like viscose, you’ll see bamboo fibres made into various types of fabric, both woven and knitted, though it is frequently used in knitted fabrics. Bamboo blends well with other fibres, so you’ll probably come across fabrics that contain different fibres along with bamboo.

What does it feel like?

Bamboo fabrics are a great choice for dressmaking as they’re so beautifully soft to wear. Like viscose, tencel and modal fabrics they also have a great drape and are breathable due to the fact they’re made from natural fibres. They have more crease resistance than these other fibres though, which is a nice bonus!

Bamboo fabrics are popular in the production of activewear as they’re absorbent and quick drying, and they’re also said to have antibacterial properties.

Washing and care

Some of these fabrics are more prone to it than others, but all of them have a tendency to shrink so it’s best to pre-wash then before use. I'd recommend using a cooler wash, such as a 30 degree cycle and then air drying afterwards. These fabrics iron well on a medium hot setting, but you may want to use a pressing cloth or iron on the reverse to prevent shine marks on the fabric.

Tips for working these fabrics

All the fabrics discussed in this post behave in a similar way so these tips will make sewing them up much more plain sailing.

• Use fine needles such microtex needles when working with woven fabrics and a smaller size ballpoint needle for jersey fabrics
• Take care when cutting out, try not to move the fabric too much and maybe use a rotary cutter and mat if you have one
• When working with lightweight wovens you can always stabilise the fabric first with spray starch, which makes the fabric less slippery and can be washed out once your garment is complete
• For more detailed information on sewing with these drapey fabrics see our post on working with slippery fabrics.

Lightweight Woven Fabrics & Pattern Recommendations

These lightweight fabrics work well for garments that need something really drapey - think floaty dresses and tops. Details such as ruffles, tucks and gathers will look great in these fabrics and will hang softly.

Medium Weight Woven Fabrics & Pattern Recommendations

These fabrics work best for garments that require a little more body, but still benefit from having a fabric with drape. You can use them for more structured dresses and tops, trousers with a looser fit and even some outerwear.

Lightweight Jersey Fabrics & Pattern Recommendations

These floaty, stretchy jersey fabrics work really well for both fitted tops and looser ones which benefit from the drapiness of the fabric. They also work well for wrap dresses, as long as the fabric isn't sheer.

Medium Weight Jersey Fabrics & Pattern Recommendations

These medium weight jersey fabrics can be used for a wide variety of garments, from simple tube skirts to snuggly sweaters and cosy joggers. As they have more drape than more traditional sweatshirting fabrics your garment will hang softly and a have a little more movement.