320 GSM Ultra-Heavyweight Winter Fabric – OEM Manufacturer

Q: Is 320 GSM too heavy for a hoodie?

It depends on the season and use case. A 320 GSM hoodie is too heavy for spring, summer, and mild autumn days — it will overheat you. But for winter (below 10°C / 50°F), a 320 GSM hoodie is exceptional — it provides genuine insulation that can replace a light jacket. Think of it as a winter-specific hoodie, not an everyday hoodie.

Q: What is Sherpa fleece at 320 GSM?

Sherpa fleece is a type of fleece fabric with a long, curly pile on one side that mimics the look and feel of sheepskin. At 320 GSM, Sherpa fleece has an extremely plush, textured back that traps maximum air for insulation. It's used for hoodies and jackets where a statement-making, ultra-cozy interior is desired. The face side remains smooth for printing.

Q: Can a 320 GSM hoodie replace a winter jacket?

In mild-to-moderate winter conditions (0°C to 10°C / 32°F to 50°F), a 320 GSM hoodie with DWR treatment can absolutely replace a light jacket — it blocks wind, retains heat, and sheds light rain. In extreme cold, wind, or snow, it's best used as a mid-layer under a waterproof shell. It bridges the gap between hoodie and jacket.

Q: What's the difference between 260 GSM and 320 GSM?

320 GSM is 23% heavier than 260 GSM, but the performance difference is more dramatic: 30–40% more thermal retention, significantly more wind resistance, and a much more rigid structure. 260 GSM is a premium everyday-cold hoodie; 320 GSM is a winter-performance garment. 260 GSM drapes and flows; 320 GSM holds its shape like armor. Choose 260 for versatility, 320 for maximum warmth.

Q: Can 320 GSM fabric be sublimated?

Only 100% polyester 320 GSM fabrics can be sublimated. Cotton and poly-cotton versions do not accept sublimation dyes. Our 100% polyester polar fleece at 320 GSM takes sublimation well, though the deeper pile can slightly reduce sharpness compared to smooth polyester. For cotton and blends, screen printing and embroidery are recommended.

OVERVIEW

What Is 320 GSM Ultra-Heavyweight Fabric?

320 GSM ultra-heavyweight fabric represents the absolute ceiling of standard sportswear textiles — a dense, insulating, structurally rigid fabric designed for one purpose: maximum warmth in cold conditions. This is where sportswear fabric crosses into outerwear territory.

"At 320 GSM, you're no longer making a hoodie — you're making a garment that functions as outerwear. A 320 GSM hoodie with DWR treatment can replace a light shell jacket in 80% of winter conditions. That's the power of this weight."

The dominant constructions at this weight are heavy 3-end fleece, Sherpa fleece, and polar fleece. Sherpa fleece in particular — with its long, curly pile backing — is almost exclusively produced at 280–350 GSM because lower weights can't support the pile structure. We also offer heavy French terry and brushed-back polyester fleece at 320 GSM.

Quality control at 320 GSM is the most stringent in our range. Every batch is tested for shrinkage (<2% post-compaction), pilling resistance (Grade 4–5), colorfastness (Grade 4–5), thermal resistance (ASTM D1518), and tensile strength per ASTM D5034. At premium price points, there is zero margin for defects.

320

Grams / m²

320 GSM ultra-heavyweight Sherpa fleece fabric showing deep plush pile texture

Quality Lab — Sialkot

FABRIC TYPES

320 GSM Fabric Options

At this extreme weight, construction defines the entire character of the garment — each type serves a specific winter purpose.

3-End

Heavy Fleece

Sherpa

Long-Pile Fleece

Polar

Deep Pile Knit

French

Heavy Terry

80/20

Cotton / Poly

100%

Polyester Fleece

GSM CONTEXT

Where 320 GSM Sits in the Spectrum

320 GSM sits at the top of the standard sportswear range — beyond this, you enter technical outerweight territory.

140 GSM
Training Tee

200 GSM
Standard Hoodie

260 GSM
Premium Hoodie

320 GSM
★ Ultra-Heavy

400 GSM
Technical / Extreme

320 GSM is the practical ceiling of sportswear fabric. Above 350 GSM, you're in technical outerwear, blanket-weight, or upholstery territory. 320 GSM is the heaviest weight that still functions as wearable sportswear. All weights tested per ASTM D3776.

PERFORMANCE FEATURES

What 320 GSM Delivers

At this weight, performance is about extreme conditions — every property is maximized for cold-weather survival.

Maximum Thermal Retention

The densest insulating layer in sportswear — traps a thick air pocket against the body for genuine cold-weather performance.

Wind Barrier

The ultra-dense knit naturally blocks wind penetration — functions as a windbreaker without any membrane or coating.

Armor-Like Durability

Virtually indestructible in normal use — resists tears, abrasion, and stretching far beyond any lighter weight.

Zero Pilling (Grade 4–5)

The fiber density at 320 GSM makes surface pilling nearly impossible — garments maintain a clean surface for years.

Outerwear Capability

With DWR treatment, a 320 GSM hoodie or jacket functions as standalone outerwear in most winter conditions.

Snow Shedding

With DWR finish, snow doesn't melt into the fabric — it beads and rolls off, keeping the garment dry and light.

Print Perfection

The thickest, most stable print surface available — inks embed deeply for maximum opacity and durability.

Rigid Structure

Garments hold their shape like architectural panels — no sagging, no stretching, no loss of form over time.

APPLICATIONS

What It's Used For

320 GSM is exclusively for cold-weather, winter, and extreme-condition garments — every application is warmth-first.

Winter Hoodies

Snowboard Jackets

Ski Mid-Layers

Heavy Fleece Jackets

Winter Track Pants

Sherpa-Lined Hoodies

Outdoor Workwear

Winter Team Gear

Premium Loungewear

Hunting / Fishing

Cold-Storage Gear

Alpine Wear

Corporate Winter Gifts

Heavy Zip-Ups

Blanket Hoodies

COMPARISON

260 GSM vs. 320 GSM vs. 380+ GSM

The ultra-heavyweight spectrum — three tiers for three levels of cold-weather demand.

Property	260 GSM	320 GSM	380+ GSM
Warmth	Moderate-high	Very high Best Balance	Extreme
Wind Blocking	Good	Excellent Best	Excellent
Hand Feel	Luxury, plush Best	Very heavy, rich	Can feel stiff
Structure	Excellent	Armor-like, rigid	Very rigid, less drape
Breathability	Moderate Best	Low	Very low
Versatility	Cool-cold weather Best	Cold weather only	Extreme cold only
Durability	Excellent	Exceptional Best	Exceptional
Pilling Resistance	Grade 4+	Grade 4–5 Best	Grade 4–5
Print Quality	Excellent Best	Very good	Good (fiber show)
Outerwear Capability	Light outerwear	Standalone outerwear Best	Standalone outerwear
Cost Per Meter	Moderate	High	Highest
Best For	Flagship hoodies	Winter / snow gear	Expedition / extreme

Pro tip: 320 GSM hits the sweet spot for "hoodie-as-outerwear." At 260 GSM, you still need a jacket in real winter. At 380+ GSM, you're in specialty territory with limited market appeal. 320 GSM is the heaviest weight with mainstream commercial viability — it's where warmth meets wearability.

PROS & CONS

Honest Assessment

Advantages

Maximum thermal retention in the sportswear fabric range — genuine winter performance
Functions as outerwear with DWR treatment — replaces a light jacket entirely
Natural wind barrier — no membrane needed for wind protection
Virtually indestructible — garments outlast lighter weights by 2–3×
Zero pilling (Grade 4–5) — maintains a clean surface for the life of the garment
Snow-shedding with DWR — ideal for snow sports and alpine conditions
Sherpa option creates a statement-making, ultra-cozy interior that drives impulse purchases
Ultra-premium perception — commands the highest retail price points

Disadvantages

Only suitable for cold weather — 3–5 months of seasonal relevance in most markets
Highest fabric cost per meter in the sportswear range
Heaviest shipping weight — significantly higher freight costs per unit
Can feel stiff and rigid if not properly constructed or garment-washed
Limited garment types — essentially hoodies, jackets, and pants only
Slowest production speed — heavy fabric moves slower through every production stage

Our mitigation: Every 320 GSM fabric is pre-compacted to guarantee under 2% shrinkage. We offer enzyme washing and garment-dyeing options that soften the initial stiffness. For shipping, we provide sea freight options that reduce logistics cost by 50–65% on heavyweight orders — critical at this fabric weight where air freight becomes disproportionately expensive.

PRINTING OPTIONS

Best Printing Methods for 320 GSM

The ultra-thick surface requires specific approaches — some methods excel, others struggle with the fiber depth.

Best Result

Screen Printing

The clear winner at 320 GSM. The ultra-thick, stable surface provides maximum ink adhesion — prints are bold, opaque, and deeply embedded. Plastisol inks perform best here because they sit on top of the dense surface without bleeding into the deep pile.

1–10 ColorsAll MaterialsMaximum OpacityBulk Pricing

Statement Maker

Embroidery

320 GSM is the ultimate embroidery canvas — the fabric's weight perfectly supports heavy stitching without any puckering or distortion. Large, dense logo designs with 10,000+ stitches look exceptional. The weight of the fabric balances the weight of the embroidery.

All MaterialsHeavy Stitching3D EffectPremium

Sublimation on 320 GSM polyester polar fleece

Polyester Only

Sublimation Printing

Available on 100% polyester 320 GSM polar fleece only. Full-color, edge-to-edge designs work well, though the deep pile can slightly soften fine details compared to smooth fabrics. Best for bold, large-format designs on snow-sports and team warm-up gear.

100% Poly OnlyBold DesignsFull-ColorPermanent

CUSTOMIZATION

Make It Yours

320 GSM fabrics offer the deepest customization options — these treatments transform the fabric character entirely.

01

Sherpa Backing

Long-pile sheepskin-texture backing for maximum insulation and a statement-making interior.

02

DWR Treatment

Durable water repellent coating — makes the outer surface shed snow, sleet, and light rain.

03

Garment Dyeing

Pigment-dye finished garments for a vintage, washed look — extremely popular at this weight.

04

Enzyme Wash

Biological softening that breaks down surface fibers for a broken-in feel from day one.

05

Heavy Brushing

Intensive brushing for maximum interior plushness — the coziest possible fleece surface.

06

Pre-Compaction

Mechanical pre-shrinking critical at this weight — guarantees under 2% shrinkage after wash.

HOW IT WORKS

Ordering Process

From first contact to delivery — a streamlined 5-step process with realistic heavyweight timelines.

Inquiry

Day 0

Samples

3–5 Days

Approval

1–2 Days

Production

20–28 Days

Delivery

5–10 Days

Total turnaround: 29–45 days from inquiry to doorstep. Heavyweight fabrics require the longest production window. Rush orders available in 20–26 days.

ORDER DETAILS

MOQ, Capacity & Lead Time

500 pcs

Minimum Order Quantity

Fabric-only: 100 meters

8K pcs/mo

Manufacturing Capacity

Scalable to 15K+ on demand

20–28 days

Production Lead Time

Rush orders: 14–18 days

FAQ

Frequently Asked Questions

Is 320 GSM too heavy for a hoodie?

It depends on the season and use case. A 320 GSM hoodie is too heavy for spring, summer, and mild autumn days — it will overheat you. But for winter (below 10°C / 50°F), a 320 GSM hoodie is exceptional — it provides genuine insulation that can replace a light jacket. Think of it as a winter-specific hoodie, not an everyday hoodie. Many successful brands market 320 GSM as their "Winter Collection" or "Heavyweight" drop.

What is Sherpa fleece at 320 GSM?

Sherpa fleece is a type of fleece fabric with a long, curly pile on one side that mimics the look and feel of sheepskin. At 320 GSM, Sherpa fleece has an extremely plush, textured back that traps maximum air for insulation. It's used for hoodies and jackets where a statement-making, ultra-cozy interior is desired. The face side remains smooth for printing. Sherpa is almost exclusively produced at 280–350 GSM because lighter weights can't support the long pile structure.

Can a 320 GSM hoodie replace a winter jacket?

In mild-to-moderate winter conditions (0°C to 10°C / 32°F to 50°F), a 320 GSM hoodie with DWR treatment can absolutely replace a light jacket — it blocks wind, retains heat, and sheds light rain and snow. In extreme cold, heavy wind, or prolonged snow exposure, it's best used as a mid-layer under a waterproof shell. It bridges the gap between hoodie and jacket beautifully.

What's the difference between 260 GSM and 320 GSM?

320 GSM is 23% heavier than 260 GSM, but the performance difference is more dramatic: 30–40% more thermal retention, significantly more wind resistance, and a much more rigid structure. 260 GSM is a premium cool-weather hoodie with beautiful drape; 320 GSM is a winter-performance garment that holds its shape like armor. 260 GSM is versatile across 6+ months; 320 GSM is a 3–5 month winter specialist. Choose 260 for a flagship everyday hoodie, 320 for a winter collection hero piece.

Can 320 GSM fabric be sublimated?

Only 100% polyester 320 GSM fabrics can be sublimated. Cotton and poly-cotton versions do not accept sublimation dyes. Our 100% polyester polar fleece at 320 GSM takes sublimation well, though the deep pile can slightly reduce sharpness on fine details compared to smooth polyester. For cotton and blends, screen printing and embroidery are the recommended methods — both perform exceptionally on this weight.

Is 320 GSM fabric too stiff?

Out of the package, 320 GSM can feel stiff — this is normal for any ultra-heavyweight fabric. We offer two solutions: enzyme washing (a biological softening process that breaks down surface fibers for a broken-in feel) and garment dyeing (which inherently softens the fabric during the dye process). Both options eliminate initial stiffness. Without treatment, the fabric softens naturally after 2–3 wash cycles.

Does 320 GSM fabric shrink more than lighter weights?

Yes — untreated cotton 320 GSM can shrink 5–7% because there's more fiber mass to contract. This is why pre-compaction is non-negotiable at this weight. We mechanically pre-compact all cotton and poly-cotton 320 GSM fabrics during finishing, which locks the fibers in place and guarantees under 2% shrinkage. 100% polyester versions shrink less than 1% naturally. Always ask your supplier about pre-compaction at 320+ GSM.

Can I get fabric samples before ordering?

Absolutely. We provide free A4-size fabric swatches (up to 3 options) shipped via DHL/FedEx at no charge. For 320 GSM, we highly recommend requesting a 3-end fleece sample, a Sherpa fleece sample, and a polar fleece sample — the difference in hand feel, warmth, and drape between these three constructions at 320 GSM is dramatic and must be evaluated in person before committing to production.

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