Essential Guide: Fabric Types And Denier Ratings

Understanding Fabric Denier

What is Denier?
Denier (D) is a unit of measurement that reflects the thickness or weight of the fibres used to weave a fabric. It is defined by the weight in grams of 9,000 meters of yarn. For example, if 9,000 meters of fabric weighs 600 grams, it is classified as 600D fabric. Generally, higher denier fabrics are stronger and thicker, while lower denier fabrics are lighter and more flexible fabrics.

• Low Denier (<400D): Lighter and more flexible, ideal for small daypacks or clothing.
• Medium Denier (400D–600D): Suitable for general-purpose backpacks and outdoor bags.
• High Denier (>600D): Heavier and more durable, best for heavy-duty backpacks and duffel bags.

However, denier alone does not determine the strength of the fabric. Factors such as the type of fibre (nylon, polyester), weave structure, and coatings also contribute to its performance in fabrics.

Common Fabrics Used in Outdoor Gear

1. Nylon
   • Description: Nylon is a synthetic polymer widely used in outdoor gear due to its durability and water resistance. It is lightweight, making it a popular choice for hiking and camping backpacks.
   • Common Types:
     • Ripstop Nylon: Reinforced with a grid of thicker threads to resist tearing, making it ideal for lightweight but durable backpacks.
     • Ballistic Nylon: A thick, durable type of nylon originally designed for military gear. It is often used in high-denier (e.g., 840D to 1680D) for heavy-duty rucksacks.
   • Pros: Strong, lightweight, and relatively water-resistant.
   • Cons: May weaken with prolonged UV exposure and can take longer to dry when wet.
2. Polyester
   • Description: Polyester is a common alternative to nylon, known for its UV resistance and colour retention. It is often less expensive than nylon but can be just as durable depending on the weave and denier.
   • Common Uses: School backpacks, daypacks, holdalls, duffel bags and medium-duty outdoor gear.
   • Pros: UV-resistant, quick-drying, and more affordable.
   • Cons: Slightly less durable than nylon in high-abrasion environments fabrics.
3. Cotton Canvas
   • Description: Traditionally used for military duffels, cotton canvas is a heavy, durable fabric but is prone to water absorption and damage if not treated.
   • Modern Use: Often blended with synthetic materials or treated with wax for waterproofing.
   • Pros: Durable and natural aesthetic.
   • Cons: Heavy and not inherently water-resistant.
4. PVC (Polyvinyl Chloride)
   • Description: PVC is a durable waterproof material often used for waterproof bags, such as those used for rafting or in highly wet conditions.
   • Pros: Waterproof and fire-resistant.
   • Cons: Difficult to repair if torn.
5. Cordura
   • Description: Cordura is a brand name often associated with high-quality, durable fabrics. It is typically made from nylon and is known for its excellent abrasion resistance.
   • Common Denier Ratings: 500D to 1000D, often used in tactical and military bags.
   • Pros: Extremely durable, resistant to wear and tear.
   • Cons: Heavier and more expensive than other fabrics.
6. X-PAC
   • Description: X-PAC is a laminated fabric composed of several layers, providing a combination of water resistance, durability, and light weight. It’s commonly used in high-performance outdoor gear.
   • Common Types: VX21 (210D), VX07 (70D), offering various levels of durability.
   • Pros: Lightweight, waterproof, and tear-resistant.
   • Cons: Can be more expensive.
7. Dyneema® and Spectra®
   • Description: Ultra-High Molecular Weight Polyethylene (UHMWPE) fibres are extremely strong and lightweight, making them ideal for high-performance gear.
   • Pros: Stronger than steel by weight, resistant to UV and chemicals, and extremely durable.
   • Cons: Expensive and limited in colour options.

Coatings and Treatments

Pay close attention to fabric types and denier ratings to ensure your gear can handle the demands of outdoor living. The durability and performance of the fabrics used in outdoor bags are often enhanced by coatings and treatments:

• Polyurethane (PU) Coating: Increases water resistance and helps maintain the fabric’s structure.
• Thermoplastic polyurethane (TPU) Coating: Durable, waterproof and abrasion resistant.
• PVC Backing: Adds waterproofing and durability.
• DWR (Durable Water Repellent): Applied to fabrics to make them water-resistant without affecting breathability.

PU vs TPU

Thermoplastic polyurethane (TPU) and polyurethane (PU) are commonly used coatings in outdoor gear, designed to enhance waterproofing and durability. Both materials serve to protect equipment from the elements, extending the lifespan of items such as bags, shoes, and other gear.

The key difference between TPU and PU lies in their manufacturing processes and chemical composition. As a result, TPU tends to be more rigid than PU. Products with a TPU coating, such as bags and footwear, often feel sturdier and less flexible compared to those with PU, which generally offers a softer, thinner texture.

When selecting outdoor gear, TPU is an excellent choice for ensuring a robust waterproof barrier, especially when combined with features like taped seams and waterproof zippers. While PU also offers a degree of water resistance, it is typically more flexible and lighter in weight, making it a suitable option for applications where flexibility and reduced bulk are priorities.

Matching Fabric to Function

When choosing a bag for outdoor activities, the fabric types and denier ratings should match the intended use:

• Lightweight Daypacks: Ripstop nylon or lower-denier polyester is suitable for short hikes or everyday use.
• Multi-Day Hiking and Camping: Mid-range denier nylon or polyester (400D–600D) offers a balance between weight and durability.
• Heavy-Duty Expeditions or Tactical Use: Higher denier ballistic nylon or Cordura (900D or above) provides maximum durability in extreme conditions.