Many friends have bought itwaterproof tarpaulinWhen using it, I found that one side was smooth and the other was rough, or the color was slightly different, which made me wonder: which side is facing up? If used in reverse, will it affect the waterproof effect?

The answer is: yes! Correctly distinguishing the front and back of waterproof tarpaulins is crucial for maximizing their performance. Different types of tarpaulins have different identification methods.

Why distinguish between positive and negative?

Waterproof principle: The waterproof function of most waterproof tarpaulins depends on the surface coating or film. The front (usually the side in contact with rainwater) coating is denser and smoother, allowing water to form droplets and roll off. The reverse side (the side in contact with the cover) may have only undergone anti slip or anti adhesion treatment, resulting in weaker waterproof ability.

Durability: The front is usually coated with anti UV agents, which can resist sunlight for a long time. If the reverse side is exposed to sunlight for a long time, it will quickly age and pulverize.

Anti slip and anti-wear: The reverse side usually has a rougher texture or is more wear-resistant to protect covered items or reduce friction with the ground.

Methods for identifying the front and back of three types of tarpaulins

Method 1: PE (polyethylene) color strip cloth

This is the easiest category to distinguish.

Front: Smooth, shiny, and brightly colored. It feels delicate when touched by hand, and water quickly condenses into beads on it. This is a waterproof surface that should face upwards towards the rainwater.

Reverse: rough, matte, dull color. Some may have simple grid patterns that give a rough feel to the touch. This is the inner level and should face downwards to touch the goods or ground.

Method 2: PVC coated cloth

The difference between the front and back of this type of tarpaulin is small, but there are still traces to follow.

Check the coating: The PVC coating on the front is usually thicker, more uniform, and brighter. The reverse coating may be slightly thinner and have a slightly lower glossiness.

Texture: Many PVC fabrics have different textures on both sides. The waterproof surface is often made of fine small squares or diagonal lines to reduce rainwater adhesion; The inner layer may have rough large particle patterns to increase slip resistance.

Check the label/seam: Regular products will have a label sewn on one corner or seam, indicating "This side up" or "TOP SIDE".

Simple test: Drop a few drops of water on each side. The side with fast rolling water droplets and minimal residue is the front.

Method 3: Traditional canvas (treated with waterproofing)

It is sometimes difficult to determine the front and back of waterproof canvas.

Judging by color: The side treated with waterproofing agents (such as paraffin or silicone) will have a darker and more moist color, while the untreated or less treated side will have a lighter and whiter color.

Feeling: The waterproof surface feels slightly "oily" or "rough" (depending on the type of waterproofing agent), while the back retains the natural roughness of cotton fabric.

Water absorption test: Drop a drop of water to see which side penetrates faster. Slow or non permeable is the waterproof front.

A universal universal law

If the above methods confuse you, please remember this safest principle:

Turn the smoother, brighter, and faster rolling side outward (upward), facing the rain and sunlight.

Place the rougher, matte, and even slightly "sticky" side inward and touch the goods or ground.