Never compare unlike materials by GSM alone
200 GSM PE and 200 GSM PVC are different constructions with different reinforcement and coating systems.
Tarp Specification Guide
For distributors, fabricators, fleet operators, contractors and industrial buyers
Buyer Decision Guide
How to Choose Tarp GSM, Oz and Thickness
Tarp GSM, ounces per square yard, mil and millimeter describe different properties. The safest way to specify a tarp is to start with the material and application, then use weight and thickness to narrow the construction—not to treat one number as a complete quality grade.
GSMMass per square meter
oz/yd²Mass per square yard
mil / mmPhysical thickness
Quick Answer
Choose the tarp by job first, numbers second.
For procurement: identify material → define exposure and handling → set a weight/thickness band → verify tensile, tear, coating adhesion and finishing → approve a physical sample.
A higher GSM or thicker sheet can add material, but it does not automatically guarantee stronger reinforcement, better welds, better UV behavior or a longer useful life.
GSM and oz are convertible
They both measure area weight. Convert them directly when comparing supplier quotations.
Mil and mm are convertible
They both measure physical thickness. One mil equals 0.001 inch, or 0.0254 mm.
Do not force GSM into mil
Mass and thickness depend on resin, coating density, scrim, finish and production method, so there is no universal conversion.
Step 1 · Understand the Units
GSM, Oz, Mil and mm Answer Different Questions
Using the correct unit prevents common sourcing errors, especially when comparing quotations from different countries.
Grams per square meter
Area weight of the finished tarp material. Useful for purchasing, shipping-weight estimates and broad duty comparison within the same material family.
Ounces per square yard
Another area-weight measurement commonly used for vinyl and canvas tarps in North American markets.
Thousandths of an inch
Physical sheet thickness. 10 mil means 0.010 inch, not 10 millimeters.
Millimeters
Metric thickness measurement often used on technical data sheets for PVC coated or laminated material.
Buyer note: GSM and oz/yd² can be converted mathematically. Mil and mm can also be converted mathematically. But weight and thickness are not interchangeable; ask the supplier for both when thickness consistency is important.
Built-In Reference Tool
Convert Tarp Weight and Thickness Units
This tool converts equivalent units only. It intentionally does not convert GSM to mil because that relationship changes with material construction.
GSM ↔ oz/yd²
Use this when one supplier quotes metric area weight and another quotes ounces per square yard.
=
Reference: 1 oz/yd² ≈ 33.906 GSM.
mil ↔ mm
Use this when a US specification is in mil and a technical data sheet is in millimeters.
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Reference: 1 mil = 0.0254 mm.
Step 2 · Use a Material-Specific Range
Practical Tarp Weight Selection Matrix
These bands are sourcing directions rather than universal standards. Final selection should be checked against reinforcement, coating system, weather exposure, handling frequency and required test values.
| Material / Market Language | Typical Direction | Common Buying Situation | What to Verify Before Ordering |
|---|---|---|---|
| Light woven PE tarp | Approx. 80–120 GSM | Short-term dust cover, indoor protection, temporary weather shielding | Weave density, lamination quality, UV treatment, grommet spacing and expected exposure |
| General / heavier PE tarp | Approx. 150–250+ GSM | Outdoor storage, agriculture, construction protection and repeated general covering | Actual finished weight, mil thickness, reinforcement, tear behavior and edge construction |
| PVC coated polyester tarp | Approx. 450–650 GSM | General industrial covers, truck and trailer covers, equipment protection, fabricated covers | Base fabric denier, yarn density, tensile/tear values, coating adhesion, weldability and UV formulation |
| Heavy PVC coated polyester | Approx. 650–900 GSM | Repeated transport use, industrial handling, long outdoor cycles, higher abrasion exposure | Duty cycle, seam/weld strength, cold crack, abrasion, finish, edge reinforcement and hardware loads |
| High-mass PVC programs | Approx. 900–1200+ GSM | Demanding industrial covers, special containment, high-wear or application-specific fabrication | Whether extra mass solves the real failure mode; handling weight, flexibility and fabrication method |
| Vinyl tarp quoted in oz/yd² | 18 oz ≈ 610 GSM; 22 oz ≈ 746 GSM | US-market truck, industrial and equipment tarp purchasing | Do not assume oz predicts exact mil; confirm both area weight and physical thickness |
Important: duty labels such as “heavy duty” are not standardized across PE, PVC, canvas and mesh. A complete specification is more useful than a marketing grade name.
Step 3 · Match the Material Family
The Same GSM Does Not Mean the Same Tarp
Weight is meaningful only when you know what the weight is made of: reinforcement, coating, lamination and finish all contribute differently.
PE Tarpaulin
Woven polyethylene construction is commonly selected for low weight, easy handling and general-purpose coverage.
- Often specified by GSM plus mil
- Useful for temporary or general outdoor coverage
- Check weave and edge reinforcement, not weight alone
PVC Coated Polyester
Polyester scrim carries structural load while PVC coating adds weather protection, surface properties and weldability.
- Often specified by GSM, oz/yd² and mm/mil
- Common for truck, industrial and fabricated covers
- Base fabric and coating adhesion strongly affect performance
Canvas / Specialty Fabric
Canvas and specialty textiles may be sold mainly by oz/yd², but water behavior and finishing can differ from coated vinyl.
- Area weight remains useful for grade comparison
- Water-resistant and waterproof should not be treated as synonyms
- Finish, breathability and shrinkage can matter as much as weight
Why GSM Can Mislead
Two 650 GSM tarps can perform differently.
Finished weight is the sum of the reinforcement, coating/lamination and surface treatment. If one construction puts more mass into coating and another puts more into the polyester reinforcement, their tensile and tear behavior can differ even when the scale reads the same.
- Base fabric denier and yarn density
- Warp and weft tensile strength
- Tear strength and puncture behavior
- PVC coating or lamination adhesion
- UV, cold-flex, mildew or flame-retardant formulation when required
- Welding, sewing, hems, webbing and grommet reinforcement
Decision Workflow
Define the failure you need to preventRain penetration, tearing, strap abrasion, wind flap, puncture, UV aging, cold cracking or excessive handling weight.
Choose the material familyPE for lighter general coverage; PVC coated polyester for weldable, repeated industrial and transport programs; other fabrics for application-specific needs.
Set a weight and thickness bandUse GSM/oz for material mass and mil/mm for physical depth. Do not create a false one-to-one conversion between them.
Specify strength and finishingAdd measurable tensile, tear, adhesion, weathering, seam/weld and reinforcement requirements where the application depends on them.
Approve a sample before scalingConfirm feel, weight, thickness, color, weld behavior and finished construction against the approved specification.
Step 4 · Select by Real Application
Which Tarp Weight and Thickness Should You Quote First?
A useful first quotation should be narrow enough to test but flexible enough to adjust after a sample review.
| Application | Starting Direction | Why | Ask About |
|---|---|---|---|
| Temporary indoor / dust cover | Light PE range | Low handling weight and easy deployment can matter more than maximum material mass. | Sheet size, tear risk, reuse cycles and grommet needs |
| Agriculture / outdoor stock cover | Medium-to-heavier PE or PVC depending reuse | Wind movement, UV and repeated covering increase stress. | UV package, reinforcement, edge loads, season length |
| Truck / trailer tarp | Commonly PVC coated polyester around 500–900 GSM | Repeated movement, rain, strap contact and fabrication favor a reinforced weldable construction. | Tensile/tear, weld strength, abrasion, cold flex, edge reinforcement, finished dimensions |
| Construction equipment cover | Medium/heavy PVC or reinforced PE | Rough surfaces and repeated handling may make puncture and abrasion more important than nominal weight alone. | Surface contact points, wind exposure, handling frequency, repair method |
| Long-term industrial outdoor cover | Higher-duty PVC construction after testing | Long exposure requires a balanced structure rather than simply the heaviest available sheet. | UV duration target, temperature range, abrasion, chemical exposure, attachment load |
| Custom fabricated tarp | Choose after panel and load design | Large finished covers can fail at seams, hems or hardware even when the base material is heavy. | Panel layout, seam type, webbing, D-rings/grommets, tie-down spacing and load direction |
Procurement Checklist
What to Put on a Tarp RFQ Instead of “Heavy Duty”
A measurable RFQ reduces ambiguity between suppliers and makes repeat orders easier to control.
Material Specification
Material familyPE woven laminated / PVC coated polyester / PVC laminated polyester / other
Finished weightTarget GSM or oz/yd², with acceptable production tolerance
ThicknessTarget mil or mm if physical depth affects your design
ReinforcementDenier, yarn density or approved supplier construction
PerformanceTensile, tear, adhesion, UV/cold/fire/mildew requirement as applicable
Finished Tarp Specification
Finished sizeState whether dimensions are cut size or finished size
SeamsHot-air/HF welding, sewing or other fabrication method
EdgesHem width, rope, webbing or double-layer reinforcement
HardwareGrommet/D-ring type, material and spacing
Commercial detailsColor, logo, packing, quantity, destination and sample requirement
DERFLEX Manufacturing Perspective
Specify the construction, not just the label.
DERFLEX supplies PVC coated and laminated tarpaulin materials as well as fabricated tarp solutions for transport, industrial, construction, agriculture and OEM programs. Published DERFLEX tarp ranges include multiple GSM directions, allowing buyers to start from the application and then match reinforcement, coating and finishing.
For repeat procurement, DERFLEX can discuss target GSM, thickness, color, roll or finished dimensions, welding/fabrication, hems, webbing, grommets and private-label packing based on the project requirement.
Weight range discussionMultiple PVC tarp GSM directions for different duty levels
Fabrication supportRoll goods, panels and custom finished tarp configurations
Performance matchingBase fabric, coating and optional functional finishes
OEM sourcingColor, dimensions, finishing, packaging and branding discussion
FAQ
Questions Buyers Ask About Tarp GSM, Oz and Thickness
What does GSM mean on a tarp?
GSM means grams per square meter. It is the mass of one square meter of finished tarp material. GSM is useful for comparing area weight within the same material family, but it does not by itself describe base-fabric strength, coating adhesion, UV formulation or finished tarp reinforcement.
How do I convert tarp ounces to GSM?
For ounces per square yard, multiply by approximately 33.906 to obtain GSM. For example, 18 oz/yd² is about 610 GSM and 22 oz/yd² is about 746 GSM.
Can GSM be converted directly to mil thickness?
No universal conversion is reliable. GSM measures mass per area, while mil measures physical depth. Different scrims, resin densities, coating ratios and finishes can produce different thicknesses at the same GSM. Request both values when both matter.
Is higher GSM always better for a tarp?
No. Higher GSM usually means more material mass, but the best specification depends on the job. Extra weight can increase handling effort and cost without solving a failure caused by weak reinforcement, poor edge design, inadequate UV resistance or unsuitable fabrication.
What GSM is commonly used for PVC truck tarps?
PVC coated polyester truck tarp programs are commonly sourced in medium-to-heavy weight ranges. A practical starting discussion is often around 500–900 GSM, then adjusted for base fabric, abrasion, weather exposure, fabrication method and expected reuse cycle.
What should I send DERFLEX for a tarp recommendation?
Send the tarp application, current material or sample if available, target GSM/oz, thickness if known, finished or roll size, color, environmental exposure, required tensile/tear values, finishing details, quantity and destination. DERFLEX can then discuss a suitable material and sampling direction.
Not sure whether you need 610 GSM, 650 GSM, 900 GSM—or a different construction?
Send DERFLEX the application, finished size, handling frequency, weather exposure and target market. The team can help narrow the material direction before sampling and quotation.
Selection ranges on this page are practical sourcing references, not universal industry grades. Confirm the final construction and test values for your application before production.