Minimum Order Quantity (MOQ): 1 pallet (typically 125–250+ bulk bags)
You should use uncoated fabric bulk bags when your product does not require the additional fine-particle or moisture barrier provided by coated woven polypropylene and when greater fabric breathability benefits the application. Uncoated FIBCs can be an excellent choice for suitable granules, pellets, coarse powders, agricultural products, minerals, recycling materials, and other dry bulk products that are not likely to sift excessively through the weave. They can also be particularly useful when filling creates significant displaced air. But “uncoated” does not automatically mean cheaper, weaker, more breathable in every complete bag configuration, or appropriate for every dry product. The product and process should make the decision.
Here is the wrong way to decide:
“Our current bag is coated. Should we switch to uncoated to save money?”
Maybe.
But that is not enough information.
What product are you filling?
How fine is it?
Does it sift?
Does it create dust?
Is moisture a concern?
How fast are you filling?
Do you use a liner?
Does the bag inflate during filling?
Where does displaced air go?
Those questions tell you whether uncoated fabric makes sense.
An uncoated FIBC uses woven polypropylene fabric without an additional polypropylene coating applied over the woven structure.
Polypropylene tapes are woven together to form the fabric.
Small openings naturally remain between those tapes.
Those openings can allow more:
Air movement.
Moisture movement.
Fine-particle migration.
Compared with comparable coated fabric.
That creates both advantages and disadvantages.
Consider uncoated fabric when:
The product is not likely to sift significantly through the weave.
Fine-particle containment through the fabric is not critical.
Moisture resistance through the fabric is not a major requirement.
Greater breathability is beneficial.
The filling process creates significant displaced air.
A separate liner provides the necessary barrier.
Coating would add cost without solving a meaningful problem.
This is one of the biggest reasons.
Product enters the FIBC.
Air inside the FIBC has to leave.
Uncoated woven fabric provides more natural pathways for air to move through the fabric than comparable coated fabric.
For some filling systems, that can be extremely useful.
Fast filling can move a lot of air.
This is especially important when product:
Falls rapidly into the FIBC.
Carries air with it.
Aerates during filling.
Is pneumatically conveyed or otherwise enters with substantial air movement.
Air management needs to be considered.
If air cannot escape efficiently, the FIBC may:
Inflate.
Balloon.
Fill inconsistently.
Back product up.
Create dust around the filling interface.
Require slower filling.
Require operator intervention.
Greater fabric breathability may help reduce these problems.
Do not assume uncoated automatically means your line can run faster.
Test it.
But when air displacement is limiting production, fabric breathability deserves attention.
Measure:
Filling rate.
Bag inflation.
Product backup.
Dust.
Operator intervention.
Total cycle time.
Granular products may be strong candidates when particles are large enough that migration through the weave is not a meaningful issue.
The key word is:
May.
Test the actual material.
Pelletized products may not require the additional fabric barrier provided by coating.
Evaluate:
Particle size.
Dust generation.
Moisture sensitivity.
Static requirements where applicable.
Abrasion.
Product value.
Some agricultural materials may benefit from greater breathability.
But agriculture covers an enormous range of products.
Do not assume all agricultural materials belong in the same FIBC.
Coarser mineral products may work well with uncoated woven polypropylene.
Fine mineral powders can be a completely different story.
Know the particle distribution.
Certain recycling applications may benefit from:
Simple woven construction.
Breathability.
Broad filling options.
Broad discharge options.
But sharpness and abrasion can become important.
This is one of the simplest decision points.
If meaningful product migration through the fabric is unlikely, you may not need coating for containment.
Then ask whether coating is needed for another reason.
If not, uncoated may make sense.
This does not mean product loss should be ignored.
It means you should measure whether it is actually occurring at a meaningful level.
If the product remains contained adequately in uncoated fabric, additional coating may not create enough value.
If the product:
Is not particularly moisture sensitive.
Is stored in controlled conditions.
Is protected through another barrier.
Does not require increased fabric moisture resistance.
Then coating may be unnecessary.
This is an important configuration.
You can use:
Uncoated woven outer FIBC + internal liner.
The outer FIBC provides structural support.
The liner provides the internal barrier.
That can be appropriate for some applications.
This is critical.
The outer fabric may be breathable.
The liner may not be.
The complete packaging system determines airflow.
If the liner traps displaced air, the breathability of the outer FIBC may provide limited benefit.
Call or Text us at 832.400.1394
Be cautious when:
The product is extremely fine.
Fine particles migrate through the weave.
Dust containment is critical.
Product loss is unacceptable.
The product is highly moisture sensitive.
The outer fabric needs stronger barrier performance.
The application requires greater contamination protection.
Uncoated fabric is not automatically wrong in these applications, but the complete barrier system needs closer evaluation.
The cheapest FIBC can become expensive quickly.
Suppose you save a small amount per bag.
But now you have:
Product loss.
Dust cleanup.
Customer complaints.
Rejected loads.
Moisture damage.
Additional housekeeping.
The cheaper bag just became the expensive bag.
Dry does not mean:
Coarse.
Non-dusty.
Moisture insensitive.
Easy flowing.
Safe from contamination.
You need more information.
This is one of the most important factors.
Ask:
What is the particle-size distribution?
Is there a fine fraction?
Can those fines migrate through the weave?
Do they create visible dust?
A product can look coarse and still contain enough fines to create problems.
Inspect what actually happens during handling.
Watch the FIBC during:
Filling.
Forklift handling.
Storage.
Transportation.
Discharge.
Look for material appearing outside the FIBC.
Then determine where it came from.
Dust may come from:
Fabric.
Seams.
Top.
Bottom.
Filling connection.
Discharge connection.
Operator handling.
Process equipment.
Find the actual source.
Uncoated does not mean seam requirements disappear.
Seams still affect:
Strength.
Containment.
Shape.
Top construction.
Bottom construction.
Fabric treatment and seam construction are separate variables.
An application may use uncoated fabric while still requiring additional seam containment.
Specify based on actual performance requirements.
Fabric choice does not determine top construction.
Possible configurations include:
Open top.
Duffle top.
Filling spout.
Other approved designs.
Open tops can provide:
Easy access.
Fast loading.
Easy air escape.
But product containment after filling may be lower.
A duffle top can provide:
Broad access.
Closure after filling.
That can work well for many suitable dry bulk products.
A filling spout can interface with:
Chutes.
Filling heads.
Process equipment.
Other filling systems.
The breathable fabric may assist air displacement, depending on the complete FIBC construction.
The bottom is a separate decision.
Choose around how product needs to leave the FIBC.
Flat bottom can make sense for:
Collection applications.
Products removed another way.
Processes where bottom discharge is unnecessary.
For suitable free-flowing materials, discharge spouts can provide controlled unloading.
Match the outlet to:
Particle size.
Flowability.
Desired discharge rate.
Receiving equipment.
Duffle bottoms may work well for:
Bulky products.
Irregular products.
Products prone to bridging.
Rapid full discharge.
But receiving equipment needs to handle the flow.
| Application Factor | 💨 Uncoated | 💧 Coated |
|---|---|---|
| High fabric breathability needed | Strong candidate | Lower |
| Natural air displacement valuable | Strong candidate | Lower |
| Fine-particle containment through fabric | Lower | Strong candidate |
| Moisture resistance through fabric | Lower | Strong candidate |
| Coarse particles | Often suitable | May be unnecessary |
| Very fine powders | Evaluate carefully | Often advantageous |
| Liner use | Compatible | Compatible |
| High-speed filling | Can be advantageous | Air management more critical |
| Automatically waterproof | No | No |
| Automatically dustproof | No | No |
| Requirement | 💨 Uncoated Fabric | 🛍️ Liner |
|---|---|---|
| Structural woven body | ✅ | No |
| Fabric breathability | Higher | Can restrict overall airflow |
| Internal barrier | Limited | Stronger potential |
| Fine-particle containment | Lower | Potentially higher |
| Moisture protection | Lower | Application dependent |
| Internal movement | None | Possible |
| Discharge interference | Usually less | Possible |
| Separate component | No | Yes |
Circular construction describes the tubular woven main body.
Uncoated describes the fabric treatment.
They can be combined.
Yes.
U-panel describes body architecture.
Uncoated describes fabric treatment.
Yes.
Four-panel FIBCs can use appropriate uncoated woven polypropylene fabric.
Yes.
Baffles help control filled shape.
Uncoated fabric provides the desired fabric characteristics.
Different functions.
Bulk density affects:
Required volume.
Target payload.
Filled geometry.
SWL.
Warehouse cube.
Transportation.
Do not finalize an FIBC without understanding it.
Do not fill until the FIBC “looks full.”
Specify the intended product weight.
Uncoated does not mean low strength.
Coated does not mean high strength.
Specify SWL separately.
Safety factor is also independent of coating.
Specify it around intended use.
Do not treat it as additional payload capacity.
Determine whether the product:
Flows freely.
Bridges.
Cakes.
Clumps.
Compacts.
Interlocks.
This matters particularly when selecting the bottom.
Abrasive material can wear:
Fabric.
Seams.
Bottom areas.
Discharge components.
The complete construction needs to handle the product.
Sharp products can create:
Puncture risk.
Localized wear.
Fabric damage.
Liner damage.
Do not hide those characteristics behind a generic product name.
If the material enters the FIBC unusually hot or cold, specify the actual operating conditions.
Uncoated does not tell you the electrostatic classification of the complete FIBC.
If static hazards matter, specify the required FIBC type separately.
It does not.
Food-contact requirements need separate specification.
It does not.
UN certification applies to the complete approved packaging design.
Fabric coating does not determine whether an FIBC is approved for repeated use.
That depends on the complete design and intended-use classification.
Specify loops around:
Forklifts.
Filling equipment.
Discharge equipment.
Operator procedures.
Loop length affects:
Forklift access.
Hanging height.
Filling setup.
Discharge setup.
Handling efficiency.
Calculate:
Body.
Loops.
Top.
Bottom.
Then verify actual equipment clearance.
Do not approve from an empty sample.
Fill it.
Measure:
Width.
Length.
Height.
Put the loaded FIBC on the intended pallet.
Measure:
Overhang.
Footprint.
Stability.
The FIBC may change shape after:
Filling.
Handling.
Storage.
Transportation.
Allow representative settling before final approval.
Consider:
Humidity.
Temperature.
Storage duration.
Loaded footprint.
Handling.
Product protection.
Indoor versus outdoor storage.
Uncoated woven fabric should not be treated as a complete moisture barrier.
Outdoor storage introduces:
Rain.
Humidity.
UV.
Condensation.
Temperature changes.
Handling damage.
Storage duration.
If those conditions matter, design for them.
Consider:
Humidity.
Temperature changes.
Vibration.
Settling.
Handling.
Transit duration.
Product containment.
Pallet movement.
The bag needs to work at the destination too.
Call or Text us at 832.400.1394
Uncoated may be the better fit when:
Greater breathability creates operational value.
Product does not sift through the weave.
Fabric moisture resistance is unnecessary.
A liner already provides the required barrier.
The filling process benefits from natural air release.
Coating provides no measurable benefit.
Coated may deserve consideration when:
Fine product migrates through uncoated fabric.
Product loss through the weave is significant.
Cleaner fabric containment is needed.
Improved moisture resistance through the fabric is important.
Reduced breathability can be properly managed.
Consider a liner when the application requires additional:
Fine-particle containment.
Moisture protection.
Product-contact protection.
Contamination control.
Chemical compatibility.
Other barrier characteristics.
But define exactly what the liner needs to accomplish.
Potentially when:
The product is sufficiently coarse.
Sifting is not a concern.
Moisture protection is unnecessary.
Contamination requirements do not require an internal barrier.
The filling process benefits from greater breathability.
The actual product performs successfully in testing.
Common mistakes include:
Choosing uncoated only because it may cost less.
Assuming uncoated means weak.
Assuming uncoated means low quality.
Assuming uncoated is always highly breathable regardless of liner.
Ignoring particle size.
Ignoring fine-particle content.
Ignoring dust.
Ignoring product migration.
Ignoring moisture sensitivity.
Assuming polypropylene means waterproof.
Ignoring seams.
Ignoring top closure.
Ignoring bottom closure.
Ignoring filling equipment.
Ignoring filling rate.
Ignoring air displacement.
Ignoring liners.
Ignoring liner airflow.
Ignoring liner movement.
Ignoring bulk density.
Ignoring target payload.
Ignoring SWL.
Ignoring safety factor.
Ignoring body construction.
Ignoring flowability.
Ignoring abrasion.
Ignoring sharp material.
Ignoring temperature.
Ignoring static requirements.
Assuming uncoated means food grade.
Assuming uncoated means UN certified.
Ignoring loops.
Ignoring filled dimensions.
Ignoring pallet fit.
Ignoring product settling.
Ignoring warehouse conditions.
Ignoring outdoor exposure.
Ignoring nationwide transportation.
Comparing only unit price.
Ask:
📦 Product: Identify the actual material.
🔬 Particle Size: Determine whether sifting through the weave is realistic.
🌫️ Dust: Evaluate the fine fraction.
⚗️ Bulk Density: Use actual data.
⚖️ Payload: Define the intended fill weight.
💨 Breathability: Determine whether greater airflow creates value.
🌬️ Air Displacement: Understand the filling process.
💧 Moisture: Confirm that lower fabric barrier performance is acceptable.
🪡 Seams: Define structural and containment requirements.
🛍️ Liner: Specify one only when required.
🔝 Top: Match the filling system.
⬇️ Bottom: Match the discharge system.
🧶 Body: Select the appropriate construction.
⚖️ SWL: Specify the required rating.
🛡️ Safety Factor: Match intended use.
⚡ Static: Define requirements separately when applicable.
🪢 Loops: Match handling equipment.
📐 Filled Geometry: Measure the loaded FIBC.
🪵 Pallet: Test the real pallet.
🏭 Warehouse: Evaluate actual storage conditions.
🚚 Transportation: Evaluate nationwide logistics.
📄 Revision: Control the approved specification.
🧪 Testing: Test the actual product and process.
Start with one question:
What would coating actually accomplish in this application?
If the answer is unclear, do not automatically specify coating.
Now examine the product.
Determine:
Particle size.
Fine-particle content.
Particle shape.
Bulk density.
Flowability.
Dust behavior.
Moisture sensitivity.
Abrasion.
Sharpness.
Temperature.
Static considerations when applicable.
Target payload.
Then evaluate filling.
How does product enter?
At what rate?
How much air is displaced?
Does the current FIBC inflate?
Does product back up?
Is filling dusty?
Would greater fabric breathability help?
Then determine:
SWL.
Safety factor.
Body construction.
Top.
Bottom.
Seams.
Liner.
Loops.
Dimensions.
Pallet.
Now test the uncoated FIBC.
Use the actual product.
Use the intended payload.
Use the actual filling equipment.
Run at the real production rate.
Measure:
Filling time.
Air displacement.
Bag inflation.
Product backup.
Dust.
Product migration.
Operator intervention.
Inspect:
Fabric.
Seams.
Top.
Bottom.
Liner if applicable.
Then put the filled FIBC on the actual pallet.
Measure:
Width.
Length.
Height.
Overhang.
Allow representative settling.
Measure again.
Store it under representative conditions.
Check:
Product containment.
Moisture exposure.
Humidity effects.
Handling.
Loaded geometry.
Move it through representative nationwide transportation conditions.
Then discharge it through the actual receiving equipment.
Measure:
Discharge time.
Flow.
Bridging.
Surging.
Dust.
Spillage.
Liner behavior.
Residual product.
Operator intervention.
Finally, compare the economics.
FIBC cost.
Filling labor.
Filling cycle time.
Product loss.
Cleanup.
Pallet utilization.
Warehouse cube.
Transportation utilization.
Discharge labor.
Damage.
Downtime.
Annual volume.
If uncoated fabric provides adequate containment and product protection while improving airflow, filling efficiency, or overall cost, use it.
If product is escaping through the weave or the application requires more moisture resistance through the fabric, coated fabric or an appropriate liner system may be the better direction.
The important thing is not to treat uncoated fabric as the “cheap version” of coated fabric.
It is a different fabric configuration with a different performance profile.
For the right product and process, that greater breathability can be exactly what the operation needs.
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