ePTFE is the membrane technology behind most high-performance waterproof-breathable jackets — including the best-known branded ones. If you’re sourcing technical outerwear, understanding what ePTFE is (and how it differs from cheaper PU membranes) helps you spec the right fabric instead of paying brand-name prices for a marketing word.
What ePTFE Is
ePTFE stands for expanded polytetrafluoroethylene — the same base polymer as PTFE (Teflon), stretched into a thin, porous film.
The magic is in the pore size. An ePTFE membrane has billions of microscopic pores that are:
- Far too small for a liquid water droplet to pass through (a raindrop is ~20,000× larger than a pore) → waterproof.
- Large enough for individual water-vapor molecules to escape → breathable.
That single structure does both jobs at once. That’s why ePTFE is the benchmark for waterproof-breathable performance.
How It’s Built Into a Jacket
An ePTFE membrane is never used alone — it’s laminated to face and/or backing fabrics to form a 2-layer, 2.5-layer, or 3-layer construction. The membrane sits between the protective outer fabric and the wearer. This is fundamentally different from a coating applied to fabric — see laminated vs coated fabric for the distinction and why it affects durability and feel.
Because the membrane is what creates the waterproof barrier, the jacket still needs taped seams to seal the stitch holes and the membrane’s performance is rated in mm (waterproof) and g / MVTR (breathable). See breathability ratings explained and waterproof vs breathable jacket.
ePTFE vs PU (Polyurethane) Membranes
The two dominant membrane types:
| ePTFE | PU (polyurethane) | |
|---|---|---|
| Mechanism | Microporous (physical pores) | Mostly monolithic (solid, vapor diffuses through) |
| Breathability | Very high | Moderate to high |
| Cost | Higher | Lower |
| Feel | Often crisper | Softer, stretchier |
| Best for | High-output, premium technical | Value tiers, everyday waterproof |
PU isn’t “bad” — modern PU membranes perform well and cost less, which makes them right for many products. The choice is about target price point and use case, not one being universally superior.
The PFC / PFAS Question
Traditional ePTFE production has been associated with PFAS chemistry, which is under increasing regulation (especially in the EU). The industry is shifting toward PFC-free / PFAS-free membranes and DWR finishes. If you sell into the EU or eco-conscious markets, ask your supplier specifically about PFC-free options rather than assuming.
(Note: a PFC-free DWR finish and a PFC-free membrane are two separate things — confirm both.)
ePTFE vs Branded Membranes
Branded waterproof-breathable membranes are, in most cases, ePTFE — you’re paying for the brand’s testing, licensing, and marketing on top of the base technology. Unbranded ePTFE and quality PU membranes can hit comparable spec numbers at lower cost. For a brand-by-brand breakdown of the trade-offs, see GORE-TEX vs alternatives.
What to Specify When You Source
- Membrane type — ePTFE or PU, driven by price point and breathability target.
- Construction — 2L / 2.5L / 3L laminate.
- Ratings — waterproof (mm) and breathability (MVTR/RET).
- PFC-free — membrane and DWR, if you need it for your markets.
- Seam-taping — required to seal the membrane’s performance into the finished garment.
Sourcing Membrane Jackets
PTOUTWEAR builds laminated waterproof-breathable jackets using ePTFE and PU membranes to your chosen construction and spec — with in-house seam-taping (5 machines), waterproof zippers, and PFC-free DWR options, ISO 9001 and SGS tested. From a 30-piece MOQ (1-piece sampling).
See our custom hardshell jackets or request a sample with your target membrane and rating spec.
