Many campers assume that tents are completely waterproof—after all, they’re designed to keep you dry, right? However, the reality is most tents are water-resistant, not fully waterproof.
Understanding the difference can help you choose the right tent and protect yourself from unexpected leaks during your camping trips.
Let’s break it all down!
Are Tents Really Waterproof?
Most tents are not 100% waterproof.
Even if a tent is advertised as waterproof, it usually means it has a high water resistance but is not immune to heavy rain over long periods.
✔ Water-resistant means it repels water to an extent but may eventually leak.
✔ Waterproof means it is completely impervious to water—which is rare for tents.
So why do manufacturers call their tents waterproof? The answer lies in waterproof ratings and materials.
Understanding Waterproof Ratings (Hydrostatic Head Value)
Most tents come with a waterproof rating, often measured as Hydrostatic Head (HH) in millimetres (mm).
💧 What is Hydrostatic Head?
It’s a measure of how much water pressure a fabric can withstand before water starts to seep through.
✔ 1,500mm – 2,000mm – Light rain protection, suitable for summer camping.
✔ 3,000mm – 5,000mm – Can handle heavy rain for long periods.
✔ 5,000mm+ – Designed for extreme weather and prolonged downpours.
⛺ Tip: If you camp in the UK’s unpredictable weather, aim for a tent with at least 3,000mm HH for reliable rain protection.
Waterproof Tent Fabrics and Coatings
Most modern tents are made from nylon or polyester, which aren’t waterproof by themselves. That’s why manufacturers add coatings to improve water resistance.
Common Waterproof Coatings:
1️⃣ Polyurethane (PU) Coating
✔ Most widely used on budget and mid-range tents.
✔ Water-resistant but breaks down over time.
✔ Can absorb moisture, leading to leakage in prolonged rain.
2️⃣ Silicone (Silnylon) Coating
✔ More durable and completely waterproof.
✔ Found in high-end expedition tents.
✔ Stronger against UV rays and lasts longer.
🛠️ Tip: If you want a tent that lasts longer, look for silicone-coated fabrics over standard polyurethane.
Canvas Tents – Naturally Waterproof?
Canvas (cotton) tents become waterproof over time by swelling when they absorb water. This process, called weathering, helps tighten the fabric weave, making it water-resistant.
However, canvas tents are heavier and require more maintenance than polyester or nylon tents.
The Importance of Waterproof Tent Seams
Even if a tent’s fabric is waterproof, seams can be a weak point where water sneaks in. To combat this, manufacturers use different seam-sealing techniques:
✔ Taped Seams – Special waterproof tape is heat-sealed over stitched areas.
✔ Inverted Seams – Stitched so that the seam is inside the tent for extra protection.
✔ Welded Seams – The most durable method, joining fabrics together using heat instead of stitching.
⛺ Tip: Always check that your tent has taped or welded seams before buying.
What About the Tent Floor?
The tent floor is just as important as the fabric and seams—you don’t want water seeping in from the ground!
✔ Most tent floors use thicker coatings for durability.
✔ ‘Bathtub-style’ floors (where the material extends up the sides) offer better protection from wet ground.
✔ Using a ground tarp or footprint underneath your tent adds extra waterproofing and durability.
How Long Does a Tent Stay Waterproof?
Tents don’t stay waterproof forever. The coatings wear down over time, especially if the tent is exposed to:
🔆 UV rays – Sunlight breaks down waterproof coatings.
🌧️ Heavy rain – Prolonged wet conditions weaken the fabric.
🧼 Improper storage – Folding up a damp tent can cause mould and mildew, damaging waterproofing.
How to Extend Your Tent’s Waterproofing:
✔ Dry it completely before storing.
✔ Reapply waterproof coatings every 1-2 years.
✔ Use a footprint/tarp under your tent to protect the floor.
What to Look for in a Waterproof Tent
When buying a tent, don’t just trust the label—look at the details:
✔ At least 3,000mm Hydrostatic Head for good rain resistance.
✔ Seam-sealed or welded seams to prevent leaks.
✔ A durable, coated floor to stop water from seeping up.
✔ Silicone-coated fabrics for long-lasting waterproofing.
Remember: Even the best tents need maintenance to stay waterproof!
By choosing the right materials, coatings, and features, you’ll stay dry and comfortable on your camping trips—whatever the weather throws at you!