TL;DR
- They are not the same kind of material. ePTFE is expanded polytetrafluoroethylene stretched into a microporous network. TPU is a monolithic hydrophilic polymer film. Most comparison errors come from treating them as interchangeable grades of one thing.
- The published ePTFE mechanism: around 30 µm thickness, roughly 82% pore volume, average pore size 0.2–0.3 µm — larger than a water vapour molecule, smaller than a water droplet.
- The wash number is the spec that decides real-world durability. Published ePTFE grades hold W/P of 10,000–20,000 mm before washing and 8,000–10,000 mm after five washes.
- Check durability data before marketing claims. A membrane tested on new fabric and a membrane tested after laundering are different products, and the published figures here make that difference visible.
Most comparisons between ePTFE and TPU start by listing two columns of performance figures and declaring a winner. That approach fails for a structural reason: the two materials achieve waterproofing through different mechanisms, and that difference determines almost everything that follows.
An expanded PTFE membrane is a stretched microporous network. Water vapour passes because the pores are larger than the vapour molecule; liquid water is held out because the pores are smaller than a droplet and the surface is hydrophobic. A hydrophilic TPU membrane is solid, with no pores at all, and relies on the polymer matrix being less permeable to liquid water than to vapour. One blocks water by geometry, the other by chemistry.
Ningbo Chaoyue New Material, with over ten years of ePTFE membrane research, publishes the microporous parameters openly: the ePTFE microporous membrane for textile is described at approximately 30 µm thickness, 82% pore volume, and 0.2–0.3 µm average pore size — explicitly sized between water vapour and water droplets.
The wider waterproof garment membrane category covers more than the standard textile grades. Alongside the general membrane there are published flame retardant membranes for firefighting and industrial apparel, moisture barrier layers for firefighting suits and emergency rescue apparel, and separate footwear film and shoe lining products. That breadth is itself informative: it shows which end uses need a membrane specified as part of a protective system rather than as a standalone weather barrier.
The Mechanism Difference That Drives Every Other Difference
Once you know that ePTFE works by pore geometry and TPU works by hydrophilic chemistry, most of the practical differences stop being a matter of opinion and start being consequences.
Why the breathability numbers are not comparable across materials
Both materials are described as breathable, and both cite a water vapour permeance standard. ePTFE grades here are published at W.V.P ≥10,000 g/m²/24h to JIS L1099 A1, with waterproofness at W/P ≥10,000, 15,000, or 20,000 mm to ISO 811 depending on grade.
The caveat that matters is the method. A microporous membrane achieves vapour transmission through open pore volume — the published 82% pore volume figure — while a solid hydrophilic film achieves it through molecular diffusion. The same standard method applied to the two materials does not produce numbers that describe the same physical process. Comparing them directly without stating the method is one of the most common errors in this category.
Why ePTFE has a hand-feel consideration
A stretched PTFE network has a characteristic feel and drape that a solid film does not. In a garment this shows up in two places: how the material handles during cutting and sewing, and how the finished garment feels against the skin. It is a real consideration for a brand specifying a membrane, and it is the kind of thing that is easier to evaluate on a sample than to settle from a datasheet.
Why durability claims need a wash figure
The published ePTFE specification includes waterproofness both before and after washing, and the difference is substantial. Taking the highest grade as an example:
This is stated openly in the product specification rather than hidden, which is the correct way to publish it. It also means that any waterproofness figure quoted without a corresponding wash figure should be treated as incomplete. Both the W/P after five washes and the standard reference are part of the same claim.
The Published ePTFE Range
Six grades are published, split by structure. The split is not cosmetic — mono-component and bi-component membranes behave differently in lamination and in service.
| Item | RG212 | RG213 | RG214 | Standard |
|---|---|---|---|---|
| Structure | Mono-component | Mono-component | Mono-component | — |
| Average thickness | 20 µm | 30 µm | 40 µm | — |
| Weight | 10–12 g | 12–14 g | 14–16 g | — |
| Width | 163 ±2 | 163 ±2 | 163 ±2 | — |
| W.V.P | ≥10,000 | ≥10,000 | ≥10,000 | JIS L1099 A1 |
| W/P | ≥10,000 | ≥15,000 | ≥20,000 | ISO 811 |
| W/P after 5 washes | ≥8,000 | ≥10,000 | ≥10,000 | ISO 811 |
| Item | RG222 | RG223 | RG224 | Standard |
|---|---|---|---|---|
| Structure | Bi-component | Bi-component | Bi-component | — |
| Average thickness | 30 µm | 35 µm | 40–50 µm | — |
| Weight | 16 g | 18 g | 20 g | — |
| Width | 163 ±2 | 163 ±2 | 163 ±2 | — |
| W.V.P | ≥8,000 | ≥8,000 | ≥8,000 | JIS L1099 A1 |
| W/P | ≥10,000 | ≥15,000 | ≥20,000 | ISO 811 |
| W/P after 5 washes | ≥8,000 | ≥10,000 | ≥10,000 | ISO 811 |
Three things in those tables are worth reading carefully rather than skimming.
First, the wash effect is consistent across all six grades: every grade loses waterproofness between the new-fabric figure and the five-wash figure. It is not a defect in one product — it is a property of the material that a specification has to account for.
Second, breathability and waterproofness move in opposite directions across the mono-component range. RG212 carries the lowest waterproofness at ≥10,000 mm and the same ≥10,000 breathability as the others. RG214 carries the highest waterproofness at ≥20,000 mm at the same breathability. If a brand needs more waterproofness, this table shows the cost is thickness and weight rather than breathability.
Third, the bi-component range sits at a lower breathability figure — ≥8,000 against ≥10,000 — at comparable waterproofness. Whether that trade is right depends entirely on the garment, which is the subject of the next section.
Matching Membrane to End Use
The published application list for this membrane range spans sportswear, cold weather clothing, rainwear, outdoor gear, specialised protective garments, military and medical uniforms, footwear, sleeping bags, and tents. That range is wide enough to make “which membrane” the wrong first question. The right first question is which part of that list the garment actually is.
Low-load recreational outerwear
Jackets and hiking layers in this category are typically specified against a moderate waterproofness requirement, where the RG212 to RG214 range is the relevant decision. Because breathability holds flat across that range, the selection reduces to how much waterproofness the wearer needs and how much bulk the garment can carry. Lower thickness means lower weight, which matters more in this category than in any other.
Extended-exposure technical garments
Cold weather clothing and technical outerwear face a different trade. The published product description identifies cold weather as a specific application, and here the thickness grade matters more because the membrane is carrying a larger share of the garment’s thermal and wind function. Higher-grade thickness carries more waterproofness headroom, which matters when the post-wash figure is the one that has to hold.
Protective and specialised garments
The published applications include firefighting, chemical protection, disaster response, and immersion operations, as well as military and medical uniforms. This is the category where membrane selection stops being a comfort question and becomes a specification question, because the garment is being relied on for protection rather than for weather.
Two features in the published range are specific to this use: a flame retardant membrane listed for firefighting and industrial apparel, and an advanced moisture barrier layer described for firefighting suits, emergency rescue apparel, and firefighting gear. If a garment falls in this category, the membrane has to be evaluated as part of a protective system rather than on waterproofness alone.
Footwear and accessories
Footwear is published as a separate application family with its own film and lining products. Membrane behaviour in footwear is different enough to be worth noting: peak pressures are lower but flex cycles are far higher, and a membrane chosen purely on waterproofness figure will be evaluated on a different failure criterion in a shoe than in a jacket.
Questions to Ask a TPU Supplier
The ePTFE side of this comparison is documented on the pages above. The TPU side has to be established by asking, because the useful differences are in the structure and the test method rather than in a headline number.
Is the TPU membrane hydrophilic or microporous?
This is the first and most consequential question, because a hydrophilic monolithic film and a microporous TPU behave differently enough that they are not comparable on the same basis. The published ePTFE description states its mechanism explicitly; ask for the equivalent statement on the TPU side and check whether the supplier gives one.
Which permeance method is quoted?
Published ePTFE figures cite JIS L1099 A1 for water vapour permeance and ISO 811 for waterproofness. TPU datasheets frequently cite a different method, and a figure from another method is not a comparable number. Ask for the method and the standard revision, then compare like with like.
What is the figure after washing?
This is the question that most often does not get asked, and the published ePTFE table shows why it should be. Six grades published here all show a reduction between the new-fabric waterproofness and the figure after five washes. A TPU specification with only a new-fabric figure is missing half of the claim.
What is the hydrostatic head tolerance across the roll?
The published ePTFE grades specify waterproofness as a minimum, with width given as 163 ±2. Ask a TPU supplier whether their figure is a minimum, a target, or a typical value, and what the tolerance is. A minimum and a typical value are different commercial commitments.
What laminate system is the membrane specified for?
Membrane performance in a garment is a property of the laminate, not of the film alone. Published guidance on this range states the membrane can be laminated with a wide variety of fabrics while retaining breathable, waterproof, and windproof performance. Ask what laminate constructions the TPU membrane is validated for, and whether the quoted figures are for the film or for a specific laminate.
If the TPU membrane is being compared against a published ePTFE range, the garment membrane enquiry channel is where a matched quote is normally requested — and asking for the wash data at the same time as the headline figures is what makes the two submissions comparable.
Specifying and Verifying a Membrane
Five checks cover the specification, and they apply to either material. They are worth working through before a claim reaches packaging.
1. Require the test method with every figure
A waterproofness figure without a standard reference is not usable. Require the method and revision for both waterproofness and permeance, so the two materials are being measured the same way.
2. Require the post-wash figure
Ask for waterproofness after a stated number of washes, on a stated fabric, using a stated method. This is the figure that represents the garment rather than the film.
3. Confirm structure and thickness together
Structure and thickness are published together for this reason. Mono-component at 20, 30, and 40 µm and bi-component at 30, 35, and 40–50 µm are different products with different characteristics, and quoting only the thickness leaves half the description out.
4. Confirm the lamination partner
A membrane is specified against a face fabric and an adhesive system. Changing either changes the performance of the laminate, so the membrane specification alone is not a garment specification.
5. Confirm roll dimensions and tolerance
Width is published as 163 ±2 across the range. Roll width and tolerance affect how the membrane runs through lamination, and a web that does not feed cleanly costs production time downstream.
6. Match the grade to the end use, not to the best figure available
The highest waterproofness grade is not automatically the correct choice. The published table shows breathability holding flat while waterproofness rises with thickness, so the selection is a requirement decision rather than a performance-maximisation decision.
Frequently Asked Questions
Is ePTFE better than TPU for waterproof garments?
Neither is better in general; they suit different uses. ePTFE achieves waterproofness through microporous geometry and typically sustains higher breathability at a given waterproofness level, while a hydrophilic TPU uses a solid matrix and is often preferred where stretch, weight, and bonding behaviour matter. The right answer depends on the garment category and the waterproofness the end use requires.
How does ePTFE membrane work?
The published description specifies approximately 30 µm thickness, roughly 82% pore volume, and 0.2 to 0.3 µm average pore size. Those pores are larger than a water vapour molecule and smaller than a water droplet, so vapour passes while liquid water is held out.
What is the difference between mono-component and bi-component ePTFE?
The published range includes both, with different characteristics. Mono-component grades are published at W.V.P ≥10,000 with thicknesses of 20, 30, and 40 µm, while bi-component grades sit at W.V.P ≥8,000 with thicknesses of 30, 35, and 40–50 µm. The bi-component range therefore carries lower breathability at comparable waterproofness.
Does waterproofness decline after washing?
Yes, and the published figures show it. Across the mono-component range, the grade at W/P ≥20,000 mm falls to ≥10,000 mm after five washes, and the ≥10,000 mm grade falls to ≥8,000 mm. Any specification quoting only the new-fabric figure is incomplete.
Which standards are used for ePTFE membrane testing?
The published specification cites JIS L1099 A1 for water vapour permeance and ISO 811 for waterproofness, including the after-wash figure. When comparing to a TPU supplier, ask which methods they quote, since a figure from a different method is not directly comparable.
Can ePTFE membrane be used for firefighting and protective garments?
Yes, and it is a published application category. The range includes a flame retardant membrane listed for firefighting and industrial apparel, and a moisture barrier layer described for firefighting suits, emergency rescue apparel, and firefighting gear, alongside military, medical, and chemical protection applications.
What thickness should I choose for a lightweight jacket?
The published mono-component range offers 20, 30, and 40 µm at 10–12 g, 12–14 g, and 14–16 g. Because breathability holds at ≥10,000 across the range while waterproofness rises with thickness, a lightweight jacket typically selects on required waterproofness and the resulting weight rather than on maximum waterproofness available.
Is ePTFE suitable for footwear as well as apparel?
The published applications include footwear and accessories alongside apparel. Membrane behaviour differs in footwear because flex cycling is much higher and pressure lower, so a membrane chosen on a waterproofness figure alone should be evaluated against a different failure criterion in a shoe than in a jacket.
Which Approach Should You Take?
Evaluate ePTFE where sustained breathability at high waterproofness is the priority and the application is technical outerwear, cold weather, or protective work. Evaluate TPU where stretch, weight, and bonding behaviour drive the design and the waterproofness requirement is moderate.
Whichever material you specify, require three things together: the test method, the post-wash figure, and the laminate construction. Any one of them stated alone is an incomplete specification, and the gap usually surfaces after the garment is already in market.
Last verified: 2026-10-21. Thickness, pore volume, pore size, grade codes, structure, weight, width, W.V.P, W/P, and post-wash W/P are as published in the Chaoyue ePTFE membrane product specification. Standards cited are JIS L1099 A1 for water vapour permeance and ISO 811 for waterproofness. TPU figures are not published here; request them from your TPU supplier with method and wash data specified.
Post time: Oct-22-2026