Is Polyester Waterproof (7 Easy To See Downsides)

Polyester, a synthetic fabric derived from petrochemicals, has become ubiquitous in our daily lives, particularly in the clothing industry.

Its resilience and versatility have raised questions about its potential properties, including its relationship with water. Is polyester truly waterproof, or does it merely repel water to a certain extent?

Is Polyester Waterproof?

No, polyester is not naturally waterproof; however, it is water-resistant. Polyester, being a synthetic fiber, possesses hydrophobic properties, which means it repels water rather than absorbing it.

This characteristic makes polyester more water-resistant than many natural fibers, like cotton, which tend to absorb moisture.

When water comes into contact with polyester, the droplets will often bead up and roll off the surface, especially if the fabric has a tight weave.

However, given enough time or pressure (as in heavy rainfall or submersion), water can still penetrate polyester.

To make polyester truly waterproof, it often needs to be treated with specific coatings or undergo processes that enhance its ability to block water completely. These treatments can include laminations, coatings, or durable water-repellent (DWR) applications.

The Basic Nature Of Polyester

Origin And Production

  • Synthetic Origin

Polyester is a man-made fiber derived primarily from petrochemicals.

Polymerization Process: It is produced through the polymerization of purified terephthalic acid (PTA) and monothylene glycol (MEG).

Molecular Structure

  • Long-chain Polymers

Polyester fibers are composed of long-chain polymers, primarily polyethylene terephthalate (PET).

  • Stable Structure

The polymer chains in polyester lend the material its strength and durability.


  • Durability

Polyester is known for its strength and resilience. It resists stretching, shrinking, and wrinkling.

  • Hydrophobic Nature

The fabric repels water, making it naturally water-resistant to some extent.

  • Thermal Stability

It can withstand higher temperatures and is often used in applications that require resistance to heat.

  • Chemical Resistance

Polyester is resistant to many chemicals, including most common solvents.

Common Uses

  • Clothing

From everyday wear, like t-shirts and pants, to specialized sportswear.

  • Home Furnishings

Used in carpets, curtains, and bedding.

  • Industrial Uses

Sails, ropes, belts, and reinforced plastics.

  • Packaging

Especially in the form of PET bottles for beverages and other liquids.

Versatility In Production

  • Blendability

Polyester is often blended with other fibers (like cotton) to combine the best qualities of both materials.

  • Yarn Varieties

It can be spun into various types of yarns, such as filament, staple, tow, and texturized.

  • Variety of Textures

Depending on its production process, polyester can be made to mimic the texture of silk, wool, and other natural fibers.

Environmental Considerations

  • Non-biodegradable

Polyester, being a synthetic fiber, does not decompose easily, posing long-term environmental challenges.

  • Microplastic Concerns

Washing polyester garments can release microplastics into waterways, impacting marine life and entering the food chain.

Overall, polyester’s basic nature is characterized by its synthetic origin, durable properties, and wide range of applications.

However, while it offers many advantages in terms of durability and versatility, its environmental impact remains a topic of concern.

Enhancing Polyester’s Water Resistance

Enhancing the water resistance of polyester is crucial for various applications, from outdoor gear to protective clothing. Here’s how it’s commonly achieved:


  • TPU (Thermoplastic Polyurethane) Lamination

A thin layer of TPU can be bonded to polyester fabric, making it both waterproof and somewhat breathable.

  • PVC (Polyvinyl Chloride) Coating

Often used for raincoats and outdoor tarps, this coating provides a waterproof barrier but can reduce the fabric’s breathability.

  • Acrylic Coating

Provides a water-resistant layer and is often used for lighter applications like umbrellas.

Durable Water Repellent (DWR) Treatments

  • Chemical Application

DWR is a chemical treatment applied to the surface of fabrics. It causes water to bead up and roll off the fabric surface instead of soaking in.

  • Retreatment

Over time, with wear and washing, DWR treatments can wear off. However, they can be reapplied to maintain water repellency.

Weave And Fabric Construction

  • Tight Weaves

Denser and tighter weaves can naturally enhance the water resistance of polyester by reducing the spaces through which water can penetrate.

  • Multi-layered Fabrics

Combining multiple layers can create barriers to water ingress. For instance, a three-layer fabric might have an outer polyester layer, a middle waterproof membrane, and an inner liner for comfort.

Blending With Other Fibers

  • Polyester-Nylon Blends

Nylon, like polyester, has good water resistance. When combined, the two can create a fabric that capitalizes on the strengths of both materials.

  • Incorporating Specialized Fibers

Some high-tech fibers, designed specifically for water resistance, can be blended with polyester to boost its performance.

Heat Setting

  • Controlled Heating

Polyester fabrics can be heat-set after weaving to tighten the weave and improve overall water resistance.

Maintenance And Care

  • Proper Cleaning

Regular cleaning without harsh chemicals or abrasive methods can preserve the water-resistant properties of treated polyester.

  • Re-application

As mentioned, treatments like DWR can wear off and might require periodic re-application.

Limitations And Considerations

  • Breathability

Enhancing water resistance can sometimes reduce the breathability of polyester. This is crucial for applications like activewear, where moisture from sweat needs to evaporate.

  • Environmental Impact

Some treatments, especially older formulations of DWR, have been associated with environmental concerns due to their chemical composition.

Overall, while polyester is naturally water-resistant due to its hydrophobic properties, various methods and treatments can enhance its resistance to water.

The choice of method often depends on the specific requirements of the end product and any trade-offs in terms of breathability, durability, and environmental impact.

Practical Applications Of Polyester In Wet Conditions

Polyester’s inherent water-resistant properties, combined with its ability to be enhanced for even greater water protection, make it ideal for numerous applications in damp or wet conditions.

Here are some of the practical uses of polyester in such environments:


  • Jackets and Outerwear

Many rain jackets and windbreakers are made of polyester because of its water-resistant nature. Enhanced treatments can make these jackets completely waterproof.

  • Active and Sportswear

Athletes and outdoor enthusiasts often wear polyester clothing because it wicks moisture away from the body, keeping the wearer dry even during intense physical activity.

  • Swimwear

Polyester is commonly used in swimwear because it retains its shape, doesn’t absorb much water, and dries quickly.

Outdoor Equipment

  • Tents and Shelters

The outer layers of many tents are made from polyester due to its ability to repel water, making it ideal for protection against rain. These layers often come with additional waterproof coatings.

  • Backpacks and Travel Gear

Many backpacks, especially those designed for hiking or camping, use polyester because it’s lightweight and can keep contents dry in light to moderate rain.

These covers protect boats from rain, dew, and other moisture, making water-resistant polyester an ideal material.

Everyday Items

  • Umbrellas

The canopy of most umbrellas is made of polyester. It’s chosen not just for its water resistance, but also its durability against wind and the elements.

Items like grill covers, furniture covers, and car covers often use polyester to protect against rain and moisture.

  • Shoe Linings

Polyester is often used in the inner linings of shoes, especially in athletic or outdoor footwear, because it wicks away moisture and keeps feet dry.

Industrial And Specialized Uses

  • Tarps

Heavy-duty polyester tarps are used in construction, transportation, and other industries to protect equipment, supplies, and cargo from rain and moisture.

  • Sails

The durability and water resistance of polyester makes it a popular choice for sails in boating and windsurfing.

  • Fishing Gear

From fishing jackets to gear bags, polyester provides protection against water splashes and wet conditions.

Home And Interiors

  • Shower Curtains

Polyester is a popular material for shower curtains because it can repel water and resist mold.

Treated polyester is used for cushions on outdoor furniture, providing comfort while repelling moisture.

  • Carpets in Wet Areas

Some indoor-outdoor carpets made of polyester are designed to resist mold and mildew, making them suitable for basements or patios.

Overall, the water-resistant properties of polyester, combined with its strength, durability, and versatility, make it a preferred material for a vast array of applications in wet conditions.

From personal apparel to industrial applications, polyester provides reliable performance and protection against moisture.

Potential Downsides Of Polyester

While polyester is celebrated for its durability, versatility, and water resistance, there are certain drawbacks and concerns associated with its use. Here are some of the potential downsides:

Environmental Concerns

  • Non-Biodegradability

Polyester is a synthetic polymer derived from petrochemicals, and it doesn’t decompose quickly. This leads to environmental challenges when polyester products are discarded.

  • Microplastic Pollution

Washing polyester garments can release microplastics into water systems, which can eventually find their way into aquatic ecosystems and harm marine life.

  • Energy-Intensive Production

The production of polyester, primarily from petrochemicals, is energy-intensive and contributes to greenhouse gas emissions.

Breathability Issues

  • Trapped Heat and Moisture

Polyester is less breathable than natural fibers like cotton. This can lead to trapped sweat and heat when worn, making it less comfortable in very hot conditions.

  • Potential For Odor

Because of its reduced breathability, bacteria can thrive in a damp environment, causing odors to develop in polyester clothing, especially after physical activity.

Skin Sensitivities

  • Allergic Reactions

Some individuals might experience allergic reactions or skin irritations when in direct contact with polyester, especially if they’re sensitive to synthetic materials.

  • Static Buildup

Polyester is prone to static electricity, which can be uncomfortable and annoying for the wearer.

Limited Natural Feel

  • Texture

Even though polyester can be made to mimic the textures of natural fibers, it often lacks the soft and luxurious feel of materials like cotton, silk, or wool.

Durability Concerns With Low-Quality Polyester

  • Wear and Tear

While polyester is generally durable, low-quality polyester fabrics can pill, snag, or thin out over time.

  • UV Sensitivity

Polyester can weaken and fade when exposed to prolonged direct sunlight.

Chemical Treatments

  • Toxic Chemical Use

Certain treatments to enhance properties like water resistance or flame resistance can involve toxic chemicals. Some of these chemicals might be harmful to the environment or the end-users.

  • Health Concerns

Chemicals used in dyeing or treating polyester might sometimes cause health concerns, especially if they are not properly set or washed out.

Sustainability Issues

  • Recycling Challenges

While polyester can be recycled, the recycling rate is relatively low. Mixed materials (like polyester-cotton blends) can also be challenging to recycle.

  • Dependence on Fossil Fuels

The production of polyester depends on non-renewable resources like petroleum.

While polyester offers numerous benefits in various applications, it’s essential to consider its potential downsides.

Addressing these challenges, especially the environmental concerns, is crucial for a sustainable future.

Advances in technology and research are leading to more eco-friendly alternatives and better production methods, but awareness and informed choices remain vital.


Polyester, a versatile and durable synthetic fabric, boasts significant advantages, especially in terms of water resistance. This makes it valuable for a myriad of applications, from clothing to industrial uses.

However, alongside its benefits, it carries environmental and practical challenges, including issues of biodegradability and breathability.

While innovations are addressing some of these concerns, consumers and industries alike must remain cognizant of both the advantages and drawbacks of polyester to make informed, sustainable choices.