Three materials, one principle
Keep liquid water and wind out, while letting the vapour the body gives off escape — that is the shared principle behind every waterproof breathable membrane. What differs is the material the membrane itself is made from: PU, PET and PTFE each have their own hydrostatic head, moisture vapour permeability (MVP) and processing characteristics. We supply all three, plus a medical-grade polycarbonate PU film for a different use case.
How waterproof and breathable can both be true
The key is the pore size in the middle layer: smaller than a water droplet, larger than a water vapour molecule. Liquid water and wind are stopped on the outside, while the much smaller vapour molecules the body gives off pass through from the inside out.
Choosing between the three materials
All three share a dry hand-feel, non-tacky surface, no carrier needed, heat resistance suitable for PU and PVC binding tape, and compliance with RSL and RoHS. They differ in hydrostatic head, MVP and processing:
| Material | Hydrostatic Head (mmH2O) | MVP (g/m2 24h) | Thickness | Weight |
|---|---|---|---|---|
| Polyurethane (PU) | > 15,000 | > 100,000 | 18 ± 2 μ | 18 ± 2 g/m2 |
| Polyester (PET) | > 10,000 | > 40,000 | 17 ± 2 μ | 17 ± 2 g/m2 |
| PTFE | > 10,000 | > 100,000 | 18 ± 2 μ | 20 ± 2 g/m2 |
- PU filmBalanced breathability and waterproofing, high colour range (black/grey/white), can also be made into a recyclable garment
- PET filmCan be made into a 100% polyester recyclable garment; excellent water vapour resistance (RET); can be laminated with non-woven fabric for medical protective wear
- PTFE filmThe material widely regarded as top-tier (the same class used by Gore-Tex); the most consistent waterproof-breathable performance, at a correspondingly higher price
Also available: medical-grade polycarbonate PU film
Not a textile breathable membrane, but a medical protective material: excellent hydrostatic head plus resistance to acid, alkali, high heat, alcohol and solvents — suited to medical protective wear and isolation gowns where chemical resistance matters.
Where it is used
- Functional apparel and outdoor gear: jackets, rainwear, hiking boot linings
- Medical protection: PET film laminated with non-woven fabric for protective wear; PC film for isolation gowns needing chemical resistance
- Sustainability-driven products: PET film can be made into a 100% polyester recyclable garment
The questions we will ask you
- What is the finished product? Functional apparel, outdoor gear, or medical protective wear?
- Your hydrostatic head and MVP targets? Target values and test standards (JIS L1092, JIS L1099, ISO 11092, etc.)
- Colour and processing method? Black/grey/white, direct lamination or with fibreglass tape edging
- Expected annual volume and lead time?
Gabriel's materials are usually not the cheapest.
But the cost of a breathable membrane is never just the unit price: insufficient hydrostatic head means complaints, low MVP means the wearer overheats, and a lamination that feels wrong after the fact means reworking the whole batch. We look at the total cost, not the number on the quote.
If all you need is the lowest unit price, the market has plenty of options. If you need a solution that genuinely meets your finished product's specification — then we should talk.
Looking for specifications and product photos
Full specifications for each material (elongation, water vapour resistance, packing) and product photos are on the product page:
→ Waterproof breathable PU film specifications
→ Waterproof breathable PET film specifications
→ Waterproof breathable PTFE film specifications
→ Medical grade PC PU film specifications
Honestly though, a phone call is usually faster. A spec sheet can tell you what options exist, but not which material suits your finished product and processing equipment — that takes a conversation.
Tell us the waterproof-breathable spec your product needs
Tell us as much as you can: the finished product category, your hydrostatic head and MVP targets, and your processing method and equipment. The more detail, the more precise our answer.
contact@yourgabriel.com
+886-2-2570-1213
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