# What is the main difference between HydraProof PE and PP films?

> Source: https://breathablefilm.com/news/knowledge-center/hydraproof-pe-vs-pp-waterproof-films/
> Author: kh_sales02
> Published: 2026-04-28
> Updated: 2026-08-28

## Key takeaways

- HydraProof™ PE and PP are both engineered for absolute liquid and vapor isolation rather than breathability, unlike Kae Hwa's breathable film series.
- HydraProof™ PE offers high elongation, excellent stretch and recovery, superior moisture sealing, and a softer feel, suiting construction membranes, isolation liners, and flexible industrial packaging.
- HydraProof™ PP prioritizes rigid strength — high tensile strength, outstanding heat resistance, and superior dimensional stability — for applications where structural integrity under load or heat matters more than flexibility.

## Frequently asked questions

### What is the main difference between HydraProof PE and PP films?

HydraProof PE and PP are both engineered for absolute liquid and vapor isolation rather than breathability, but they suit different mechanical and thermal needs. PE offers high elongation and excellent stretch and recovery with superior moisture sealing and a softer feel, so it conforms to irregular surfaces without tearing, making it well suited to construction membranes, isolation liners, and flexible industrial packaging. PP instead prioritizes rigid strength, with high tensile strength, outstanding heat resistance, and superior dimensional stability, making it the better choice when structural integrity under mechanical load or heat matters more than flexibility.

### How is HydraProof™ different from Kae Hwa's breathable film series?

Unlike Kae Hwa's breathable series, which is engineered to let vapor pass while blocking liquid, HydraProof™ is engineered for absolute liquid and vapor isolation — it's a non-breathable barrier film, so the choice between HydraProof™ and a breathable series depends on whether the application needs vapor to escape at all.