340 GSM Heavyweight Fabric
The industry-standard shell weight for insulated outerwear. Rugged enough to hold down fill without rippling, weather-sealed with DWR & PU coatings — built for puffer jackets, parkas, and winter performance gear.
What Is 340 GSM Fabric?
340 GSM fabric is a heavyweight performance shell specifically engineered as the outer layer for insulated garments. At this density, the fabric provides enough structural rigidity to hold down or synthetic fill panels flat and even — preventing the rippling, bunching, and cold-spot formation that plagues lighter shells.
We manufacture 340 GSM shells in both high-tenacity nylon and recycled polyester, with optional DWR treatment, PU coating (5,000–10,000mm waterproof), and full membrane lamination (20,000mm+) for extreme conditions.
Every roll is tested for tear strength (ASTM D1424), waterproof rating (AATCC 127), hydrostatic head pressure, and seam-seal compatibility before it leaves our Sialkot facility.
Available 340 GSM Variants
Six configurations engineered for different end-uses — from team puffers to expedition parkas.
Where 340 GSM Fits
Understanding where this weight sits in the full fabric range — and why it's the go-to for insulated outerwear.
Why 340 GSM Performs
The specific properties that make this weight class the industry standard for insulated outerwear shells.
Fill Retention
Structural density prevents down and synthetic insulation from shifting, bunching, or creating cold spots over time.
Puncture Resistance
High GSM eliminates feather poke-through — down quills and synthetic fibers stay contained within quilt channels.
Wind Block
Dense weave structure creates an effective wind barrier even before coatings are applied — critical for winter performance.
Coating Bond
Heavier fabric bonds more reliably with PU coatings and membrane laminations — fewer delamination issues in the field.
Seam Strength
Thicker material holds stitch lines and tape seals securely — essential for waterproof garment construction at seam points.
Shape Retention
Garments hold their structured silhouette wash after wash — no sagging, stretching, or loss of panel alignment.
Premium Hand Feel
Despite the weight, high-tenacity yarns and calendering produce a smooth, crisp hand — not stiff or cardboard-like.
What It's Used For
340 GSM shells dominate the insulated outerwear category across performance, fashion, and workwear segments.
Shell Weight Comparison
How 340 GSM stacks up against lighter and heavier shell options across key performance metrics.
| Property | 200 GSM | 340 GSM | 450 GSM |
|---|---|---|---|
| Fill Support | Minimal — fill shifts | Excellent — holds panels flat Best | Overkill — adds weight |
| Puncture Resistance | Feather poke-through likely | Strong barrier Best | Maximum but unnecessary |
| Wind Protection | Requires coating | Naturally wind-blocking Best | Naturally wind-blocking |
| Garment Weight | Very light Lightest | Moderate | Heavy Heaviest |
| Packability | Highly compressible Best | Moderate — compresses well | Bulky — hard to pack |
| Coating Bond | Can delaminate | Strong, reliable bond Best | Strong bond |
| Seam Strength | Adequate for light use | Excellent for taped seams Best | Very strong |
| Hand Feel | Soft, flexible Softest | Crisp, premium | Stiff, boardy Stiffest |
| Cost Per Meter | Lowest Cheapest | Moderate | Highest Priciest |
| Best For | Light shells, liners | Puffers, parkas, ski Versatile | Tactical, industrial |
Honest Assessment
- Optimal density for holding down and synthetic insulation flat
- Eliminates feather poke-through in down-filled garments
- Naturally wind-resistant even without additional coatings
- Superior PU coating and membrane lamination adhesion
- Strong seam integrity — ideal for fully taped waterproof construction
- Maintains garment shape and silhouette over hundreds of wash cycles
- Versatile across puffers, parkas, ski jackets, and workwear
- Premium crisp hand feel despite the weight
- Heavier than midweight shells — not suitable for packable ultralight gear
- 15–30% higher material cost than 200–250 GSM alternatives
- Less breathable than lighter fabrics — moisture can accumulate during high-output activity
- Longer production lead time due to heavier fabric handling
- Not suitable for sublimation on nylon (polyester variant available)
- Overkill for non-insulated garments — adds unnecessary cost and weight
Three Levels of Protection
340 GSM's density makes it the ideal base for durable, long-lasting water protection treatments.
DWR Treatment
Durable water repellent finish causes water to bead and roll off the surface. Not fully waterproof — ideal for light rain and snow. Retains full breathability and fabric hand feel.
PU Coating
Polyurethane coating applied to the fabric back creates a waterproof barrier rated 5,000–10,000mm. The standard choice for puffer jackets — fully waterproof, seam-tape compatible, and cost-effective.
Membrane Lamination
PTFE or TPU membrane laminated between fabric layers. Waterproof to 20,000mm+ with breathability of 10,000–15,000 g/m²/24hr. For expedition-grade parkas and premium alpine jackets.
Make It Yours
340 GSM is one of the most treatment-friendly weights — almost any finish can be applied with excellent adhesion.
Fiber Type
Nylon, recycled polyester, or standard polyester — each with distinct performance profiles.
Weave Structure
Taffeta, ripstop, oxford, or plain weave — selected based on end-use and aesthetic needs.
Coating Level
DWR, PU coating (5K–10K), or membrane lamination (20K+) — matched to your waterproof spec.
Color & Dyeing
Pantone-matched solid colors, heathered effects, or solution-dyed for maximum colorfastness.
Finish Treatments
Anti-pilling, UV stabilizer, anti-static, or antimicrobial — layered on top of base coating.
Print Method
Screen printing, heat transfer, or sublimation (polyester only) for branded outerwear.
Ordering Process
From first contact to delivery — a streamlined 5-step process for bulk fabric orders.
Inquiry
Day 0Samples
3–5 DaysApproval
1–2 DaysProduction
18–25 DaysDelivery
4–7 DaysMOQ, Capacity & Lead Time
Frequently Asked Questions
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Ready to Start Your 340 GSM Order?
Get a detailed quote with pricing, lead time, and free fabric samples — typically within 4 business hours.