Minimum Order Quantity (MOQ): 1 pallet (typically 125–250+ bulk bags)
The biggest advantage of uncoated fabric bulk bags is breathability. Because the woven polypropylene fabric does not have an additional coating closing the natural openings in the weave, air can generally move through the fabric more readily. That can be extremely useful during filling, especially when the product displaces significant amounts of air. The biggest disadvantage is the other side of that exact same feature: the open weave can allow more fine-particle migration and moisture movement through the fabric. Uncoated FIBCs can be excellent for suitable granules, pellets, coarse powders, agricultural materials, minerals, recycling products, and other dry bulk solids—but they are not automatically the right choice for every product.
Here is the easiest way to understand uncoated fabric:
The weave is more open.
That means air can move through it more easily.
Good.
But very fine particles and moisture can also move through it more easily.
Potentially bad.
That is the tradeoff.
An uncoated FIBC is made from woven polypropylene fabric without the additional polypropylene coating commonly used to close more of the natural openings between the woven tapes.
Those openings influence how the fabric handles:
Air.
Fine particles.
Moisture.
Uncoated fabric generally provides more breathability than comparable coated fabric.
Potential advantages include:
Greater fabric breathability.
Better natural air displacement.
Potentially easier filling.
Potentially faster filling cycles.
Good suitability for many coarse products.
Compatibility with liners.
Compatibility with multiple FIBC constructions.
Compatibility with different top and bottom styles.
Potential cost savings when coating provides no operational value.
Potential disadvantages include:
Greater fine-particle migration through the weave.
Lower moisture resistance through the fabric.
Potential dust problems.
Potential product loss.
Potentially greater housekeeping requirements.
Reduced suitability for certain moisture-sensitive products without additional protection.
Possible need for a liner or additional containment features.
| Feature | Advantage | Disadvantage |
|---|---|---|
| 💨 Breathability | Higher | Less fabric barrier |
| 🌬️ Air displacement | Better potential | Depends on complete bag |
| ⚙️ Filling | Can improve filling efficiency | Does not solve every filling problem |
| 🌫️ Fine particles | Fine material can escape more easily | Lower containment potential |
| 💧 Moisture | Simple woven construction | Lower resistance through fabric |
| 🛍️ Liners | Compatible | Liner may reduce airflow advantage |
| 📦 Coarse products | Often a strong fit | Product must still be tested |
| 💰 Cost | Avoids unnecessary coating | Loss/cleanup can erase savings |
| 🧶 Construction | Works with many FIBC styles | Does not determine bag performance |
This is the headline advantage.
Uncoated woven polypropylene allows more natural air movement through the fabric.
That can create real operational value.
Product enters the FIBC.
Air inside needs to leave.
Uncoated fabric can provide additional paths for displaced air.
This can be especially useful when filling quickly.
If displaced air cannot escape efficiently, the FIBC may balloon during filling.
More breathable fabric may help reduce this behavior.
Poor air displacement can interfere with incoming product.
The result may be:
Product backup.
Slower filling.
Dust.
Operator intervention.
Greater breathability can potentially help.
If fabric airflow is currently limiting the process, uncoated fabric may improve throughput.
But measure it.
Do not assume.
Some products carry substantial air during filling.
If that air needs to escape quickly, fabric breathability can become valuable.
If particles are too large to migrate meaningfully through the weave, the additional barrier from coating may provide little value.
Many pelletized products may not require coated fabric.
Evaluate:
Particle size.
Fine-particle content.
Dust.
Moisture sensitivity.
Abrasion.
Static requirements where applicable.
Some agricultural materials may benefit from increased airflow.
But evaluate the actual product.
Agricultural products vary tremendously.
Fine mineral powder and coarse mineral material are not the same packaging application.
Coarser materials may perform well in uncoated fabric.
Certain recycling materials may not require additional fabric barrier performance.
In those cases, uncoated woven polypropylene can be a practical solution.
If coating solves no problem, why buy it?
Industrial packaging should be specified around performance.
Not around adding features.
This is important.
Uncoated does not mean unlined.
You can combine:
Uncoated woven outer FIBC + internal liner.
That allows the structural outer bag and internal barrier to perform separate functions.
Uncoated woven polypropylene can be used with appropriate:
Circular construction.
U-panel construction.
Four-panel construction.
Baffle construction.
Other approved designs.
Possible configurations include:
Open top.
Duffle top.
Filling spout.
Other approved designs.
Possible configurations include:
Flat bottom.
Discharge spout.
Duffle bottom.
Other approved designs.
Sometimes you do not need:
Coating.
Complex barrier construction.
Additional components.
You need a well-designed woven FIBC that handles the product efficiently.
Simple can be excellent.
Call or Text us at 832.400.1394
This is the major tradeoff.
The openings that allow air to escape can also allow sufficiently fine material to migrate through the fabric.
With very fine products, you may see:
Powder outside the FIBC.
Dust on pallets.
Dust on warehouse floors.
Dust on forklifts.
Product loss.
Customer complaints.
Even small losses matter when:
Product value is high.
Annual volume is high.
Cleanup is expensive.
Customers demand cleaner loads.
Measure the economics.
Dust does not disappear.
Someone cleans it.
That means:
Labor.
Downtime.
Equipment cleaning.
Warehouse cleaning.
Potential contamination concerns.
The natural openings in the weave create more pathways for moisture movement than comparable coated fabric.
For moisture-sensitive products, this can matter.
Do not make this assumption.
Water can potentially move through:
Fabric.
Seams.
Top.
Bottom.
Closures.
Other interfaces.
Some products can:
Cake.
Clump.
Harden.
Lose flowability.
Degrade.
If moisture exposure creates meaningful product problems, evaluate the complete barrier system.
A liner may be necessary when greater:
Fine-particle containment.
Moisture protection.
Product-contact protection.
Contamination control.
Other barrier performance.
Is required.
This is where things get interesting.
You choose uncoated fabric for airflow.
Then you install a relatively closed liner inside it.
Now where does the air go?
The complete packaging system matters.
A liner can:
Shift.
Wrinkle.
Fold.
Move during filling.
Restrict product flow.
Interfere with discharge.
Trap residual product.
Test it.
Fine particles may also escape through:
Seams.
Needle penetrations.
Top construction.
Bottom construction.
You still need to evaluate the entire FIBC.
Breathability helps only so much.
You can still have problems from:
Wrong filling spout.
Poor equipment connection.
Excessive filling rate.
Aerated product.
Bad liner configuration.
Improper bag setup.
If your product bridges through the outlet, breathable fabric will not fix it.
This is not really a disadvantage of the fabric.
It is a disadvantage of buyers misunderstanding the terminology.
Coated versus uncoated does not define Safe Working Load.
Same rule.
Safety factor must be specified separately.
Fabric treatment is one variable.
A sophisticated FIBC can still use uncoated fabric.
Food-contact requirements are separate.
UN certification applies to the complete approved packaging design.
Static requirements must be evaluated separately.
| Requirement | 💨 Uncoated | 💧 Coated |
|---|---|---|
| Fabric breathability | Higher | Lower |
| Natural air displacement | Better potential | Reduced |
| Fine-particle containment through weave | Lower | Better potential |
| Moisture resistance through fabric | Lower | Better potential |
| Coarse products | Often suitable | May be unnecessary |
| Very fine powders | More caution required | Often advantageous |
| High-speed filling | Can be advantageous | Air management more important |
| Liner compatibility | ✅ | ✅ |
| Automatically waterproof | No | No |
| Automatically dustproof | No | No |
| Consideration | 💨 Uncoated Fabric | 🛍️ Liner |
|---|---|---|
| Structural woven body | ✅ | No |
| Breathability | Higher | Can restrict airflow |
| Fine-particle barrier | Lower | Potentially higher |
| Moisture barrier | Lower | Application dependent |
| Separate component | No | Yes |
| Can shift | No | Yes |
| Can wrinkle | No | Yes |
| Can interfere with discharge | Usually less directly | Possible |
| Automatically waterproof | No | No |
Circular describes the tubular woven main body.
Uncoated describes fabric treatment.
The two can be combined.
U-panel FIBCs can also use uncoated woven polypropylene.
Four-panel FIBCs can use uncoated fabric.
Remember that panel seams still matter for containment.
Baffles control filled shape.
Uncoated fabric affects barrier and airflow characteristics.
Different functions.
This is where its advantages can become measurable.
Test:
Bag setup.
Filling connection.
Filling rate.
Air displacement.
Bag inflation.
Dust.
Total cycle time.
Do not rely on theory alone.
Watch the FIBC.
Does air escape naturally?
Does the bag inflate excessively?
Does product back up?
Does dust appear around the filling connection?
Does the operator need to pause filling?
Measure what actually happens.
Fabric breathability usually does not determine discharge performance by itself.
Discharge is more heavily influenced by:
Product flowability.
Bottom construction.
Outlet size.
Receiving equipment.
Liner.
Product condition.
But moisture exposure can indirectly affect discharge if the product cakes or clumps.
Think about the complete package.
Fabric.
Seams.
Top.
Bottom.
Liner.
Closures.
Storage.
Transportation.
Uncoated fabric provides less resistance through the weave than coated fabric, but fabric is only one potential moisture path.
Use caution.
Outdoor conditions may include:
Rain.
Humidity.
UV.
Temperature swings.
Condensation.
Standing water.
Handling damage.
Storage duration.
Do not treat an uncoated FIBC as an outdoor moisture barrier.
Polypropylene exposed to sunlight can be affected by UV over time.
If outdoor exposure is meaningful, define the actual requirement.
Moisture can originate from temperature changes and humidity—not just direct rain.
Evaluate the complete environment.
Particle size is one of the most important decision factors.
Coarse product?
Uncoated may be perfectly suitable.
Extremely fine product?
You need to look closely at containment.
Do not look only at average particle size.
A product may contain enough fines to create significant dust even when most of the material is relatively coarse.
Bulk density affects:
Required volume.
Target payload.
Filled dimensions.
SWL.
Pallet fit.
Warehouse cube.
Transportation.
Specify it.
Know whether the product:
Flows freely.
Bridges.
Cakes.
Clumps.
Compacts.
Interlocks.
That influences filling and discharge decisions.
Abrasive materials can wear the woven fabric.
Evaluate the actual product.
Sharp or angular particles may create:
Puncture risk.
Localized wear.
Fabric damage.
Liner damage.
Define unusual product temperatures before selecting the FIBC.
Do not use “uncoated” as a substitute for electrostatic classification.
Specify the required FIBC type separately when applicable.
Uncoated fabric may be used in suitable food applications when the complete FIBC meets the applicable requirements.
But uncoated does not automatically mean food grade.
The complete packaging design must satisfy applicable requirements.
Fabric treatment alone does not determine UN certification.
Coating does not determine whether an FIBC can be reused.
The complete approved design and intended-use classification matter.
Loop requirements still need to be specified around:
Forklifts.
Filling equipment.
Discharge equipment.
Operator procedures.
Calculate:
Body height.
Loop length.
Top.
Bottom.
Then compare the suspended package with the actual equipment.
Fabric treatment does not determine the final loaded footprint.
Consider:
Body construction.
Empty dimensions.
Bulk density.
Payload.
Product settling.
Baffles.
Fill the FIBC.
Place it on the real pallet.
Measure:
Width.
Length.
Height.
Overhang.
Do not approve from empty dimensions alone.
Evaluate:
Loaded footprint.
Storage height.
Handling clearance.
Pallet stability.
Humidity.
Product protection.
Warehouse cube.
Consider:
Settling.
Vibration.
Handling.
Humidity.
Temperature changes.
Transit duration.
Pallet movement.
Product containment.
The bag has to work after it leaves your facility.
Call or Text us at 832.400.1394
Uncoated fabric becomes attractive when:
The product is sufficiently coarse.
Fine-particle migration is minimal.
Moisture resistance through the fabric is unnecessary.
Breathability creates filling benefits.
Natural air displacement improves the process.
A liner handles the required internal barrier.
Coating would provide little measurable value.
Uncoated fabric deserves more caution when:
The product is extremely fine.
Product sifts through the weave.
Dust is unacceptable.
Product loss is expensive.
The product is highly moisture sensitive.
Cleanliness requirements are demanding.
The outer fabric needs greater barrier performance.
Do not compare only purchase price.
Compare:
Bag price.
Filling labor.
Filling cycle time.
Product loss.
Dust cleanup.
Product damage.
Rejected loads.
Pallet utilization.
Warehouse cube.
Transportation utilization.
Discharge labor.
Residual product.
Downtime.
Annual volume.
An uncoated FIBC that saves money and fills faster can be an excellent choice.
An uncoated FIBC that leaks valuable powder everywhere can be an expensive disaster.
Common mistakes include:
Assuming uncoated means inferior.
Assuming uncoated means weak.
Assuming uncoated means cheap.
Assuming uncoated is always cheaper overall.
Assuming uncoated automatically fills faster.
Ignoring particle size.
Ignoring fine-particle content.
Ignoring dust.
Ignoring product migration.
Ignoring moisture sensitivity.
Assuming polypropylene means waterproof.
Ignoring seams.
Ignoring needle holes.
Ignoring top construction.
Ignoring bottom construction.
Ignoring filling equipment.
Ignoring filling rate.
Ignoring air displacement.
Ignoring aerated product behavior.
Ignoring liners.
Assuming uncoated plus liner remains highly breathable.
Ignoring liner movement.
Ignoring liner discharge behavior.
Ignoring bulk density.
Ignoring payload.
Ignoring SWL.
Ignoring safety factor.
Ignoring body construction.
Ignoring flowability.
Ignoring abrasion.
Ignoring sharp particles.
Ignoring temperature.
Ignoring static requirements.
Assuming uncoated means food grade.
Assuming uncoated means UN certified.
Ignoring loops.
Ignoring hanging height.
Ignoring filled dimensions.
Ignoring pallet fit.
Ignoring settling.
Ignoring warehouse conditions.
Ignoring outdoor exposure.
Ignoring nationwide transportation.
Comparing only unit price.
Ask:
✅ Major advantages: greater fabric breathability, improved natural air displacement, potential filling-efficiency benefits, suitability for many coarse products, compatibility with liners, broad compatibility with different FIBC constructions, and avoiding unnecessary coating when additional fabric barrier performance is not required.
⚠️ Major disadvantages: greater potential for fine-particle migration, lower moisture resistance through the fabric, possible product loss, possible dust and housekeeping issues, and the potential need for liners or additional containment features in more demanding applications.
Start with 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 ask:
What problem would coating solve?
If the answer is:
None.
That is important.
Now ask:
Would the greater breathability of uncoated fabric improve filling?
If yes, uncoated deserves serious consideration.
Then define:
SWL.
Safety factor.
Body construction.
Top.
Bottom.
Seams.
Liner if required.
Loops.
Dimensions.
Pallet.
Filling system.
Discharge system.
Now test.
Fill the FIBC with the actual product.
Use the intended payload.
Use the real filling equipment.
Run at the intended production speed.
Measure:
Filling cycle time.
Air displacement.
Bag inflation.
Product backup.
Dust.
Product migration.
Operator intervention.
Inspect:
Fabric.
Seams.
Top.
Bottom.
Liner if applicable.
Then place the loaded FIBC on the actual pallet.
Measure:
Width.
Length.
Height.
Overhang.
Allow representative settling.
Measure again.
Store it under representative conditions.
Evaluate:
Humidity.
Temperature.
Product containment.
Moisture exposure.
Handling.
Loaded geometry.
Then move it through representative nationwide transportation conditions.
Finally, discharge through the actual receiving system.
Measure:
Discharge time.
Flow.
Bridging.
Surging.
Dust.
Spillage.
Liner interference.
Residual product.
Operator intervention.
Now calculate total cost.
FIBC price.
Filling labor.
Cycle time.
Product loss.
Cleanup.
Pallet utilization.
Warehouse cube.
Transportation utilization.
Discharge labor.
Damage.
Downtime.
Annual volume.
If uncoated fabric gives you adequate containment and protection while providing better airflow or eliminating an unnecessary coating expense, the advantages may clearly outweigh the disadvantages.
If the product sifts through the weave, creates unacceptable dust, or requires greater moisture resistance through the fabric, the disadvantages may outweigh the breathability benefit.
That is the real tradeoff.
Uncoated fabric gives you greater breathability—but less fabric barrier.
Whether that is an advantage or a disadvantage depends entirely on what you are putting inside the bag and what happens to that bag from filling line to final discharge.
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