To answer you simply and directly: Yes, PVC tensile fabric is 100% waterproof.
In fact, rain and water resistance are not only its basic functions, but also the main reason why it excels in the construction field. This material was designed to provide an "indestructible umbrella" for people and facilities below, even in extreme outdoor weather conditions.

Here's an introduction to the waterproof performance of PVC tensile fabric:

1. Why is it completely waterproof?

This is mainly due to its construction.
Physical barrier: The core of PVC tensile fabric is an extremely dense fabric, which is wrapped in a thick, continuous layer of polyvinyl chloride (PVC) coating. This coating acts like a plastic film, which is impermeable at the molecular level.
Seamless bonding: This material is not sewn together with needles and threads (which would create holes for water leakage), but rather "melted" together using high-temperature welding or high-frequency welding. This creates a seamless joint, giving rainwater no chance to penetrate.

2. What are its special characteristics in rainy weather?

Lotus effect: High-end PVC tensile fabric usually has a very smooth coating on its surface (such as PVDF). Rainwater landing on it quickly gathers into droplets and rolls off, just like water droplets on a lotus leaf. It doesn't penetrate and doesn't make the fabric heavier.
Self-cleaning function: This waterproof property also brings an added benefit – as the rainwater flows away, it also carries away surface dust and dirt. This is why many membrane structure buildings look cleaner after it rains.

3. Drainage advantages due to tension

No water accumulation: PVC tensile fabric must be used under tension. Because it is stretched tightly, it forms a certain curvature and slope, so rainwater quickly drains away along the designed curves, unlike ordinary canvas awnings that can accumulate large "puddles" of water.
Corrosion resistance: Traditional metal roofs may rust and leak over time, but this material, due to its plastic coating, is completely resistant to acid rain and humid air corrosion, ensuring very stable waterproof performance.

4. Points to Note

Although the material itself is completely waterproof, there are a few details to pay attention to during use:
Installation Quality: If the material is not stretched tightly enough during installation, or if the drainage slope is not properly designed, it may lead to localized water accumulation. While the pressure from prolonged water accumulation won't cause the fabric to rot, it may lead to leakage at the joints.
Maintenance: Although it is very durable, if it is scratched by sharp objects falling from a height, even a small tear will damage the waterproof layer. In this case, it needs to be repaired promptly using special heat-sealable patches.

5. Common Waterproof Applications

Because of its extremely strong waterproofing capabilities, it is widely used in:
Open-air grandstands: Allowing spectators to watch games comfortably even in the rain.
Logistics loading and unloading areas: Protecting goods from getting wet during handling.
Landscape walkways: Providing long-term rain protection for pedestrian streets or station entrances.