When it comes to choosing a tent for your outdoor adventures, one crucial aspect to consider is its waterproof rating. Understanding waterproof ratings is essential for selecting a reliable and weather-resistant tent. In this article, we will explore the basics of tent waterproof ratings, explaining the terminology and their significance. By the end, you’ll have a clear understanding of how waterproof ratings work and their importance in making an informed tent-buying decision. Let’s dive in!
How is Tent’s Waterproof Rating Described?
When it comes to tent waterproof ratings, you’ll often come across specific terms used in the specifications and descriptions of tents. Let’s explore these terms and understand how they describe the waterproofness of a tent.
1. Waterproofness in mm H2O:
This term refers to the water pressure that a waterproof fabric can withstand before water starts to penetrate it. To determine this rating, manufacturers conduct a test where the fabric is placed at the bottom of a cylinder without a bottom, and a water column is created above it. The rating indicates the height of the water column in millimeters that the fabric can withstand before it begins to leak.
For example, a rating of 1000 mm means the fabric can hold a water column of 1 meter above it without any leakage. Visualizing this impressive level of waterproofness helps you understand the fabric’s capability to withstand water pressure.
2. Hydrostatic Head Rating in mm:
The term “hydrostatic head” is another way to describe a tent’s waterproof rating. It essentially measures the water pressure required to penetrate the fabric. The hydrostatic head rating is also measured in millimeters and provides information similar to the waterproofness rating in mm H2O.
Both waterproofness in mm H2O and hydrostatic head rating in mm convey the same information regarding the fabric’s resistance to water pressure.
3. Rating in PSI:
The third term you may encounter is the rating in PSI, which stands for “pounds per square inch.” This measurement indicates the water column pressure in pounds when the area of the fabric is 1 square inch. While it is a different unit of measurement, the concept remains the same. Conversion tables are often available to provide a comparison between ratings in mm and PSI.
Waterproof Rating
| Rating in mm | Rating in PSI |
|---|---|
| 500 | 0.71 |
| 1000 | 1.42 |
| 1500 | 2.13 |
| 2000 | 2.84 |
| 3000 | 4.27 |
| 5000 | 7.11 |
How Much Waterproofness is Enough?
When considering the waterproofness of a tent, it’s essential to determine how much is sufficient for your specific camping needs. While an ordinary umbrella may have a waterproof rating of around 400-500 mm, the requirements for a tent differ due to various factors.
Tent Fly and Walls:
For the tent’s fly (the outer layer) and walls, a waterproof rating within the range of 400-500 mm may be considered sufficient. These parts of the tent are primarily responsible for protecting against rain and moisture. However, it’s important to note that many waterproof tents often offer higher ratings for enhanced durability and longevity.
Tent Floors and Water Pressure:
The tent floor is a critical area that requires higher waterproofness due to potential abrasion and the presence of ground moisture. It’s important to consider the pressure exerted on the tent floor, both from your body weight and potential groundwater. Even if you press down on the floor, water can potentially seep through if the fabric isn’t adequately waterproof.
In family camping tents and other models, the floor is typically made of a thick, completely waterproof material like polyethylene. These materials are cost-effective and provide reliable protection against moisture from the ground. The thicker the material, the better it withstands water penetration.
Tents for Summer Camping:
Most of the tents available on the site are designed for summer camping. These tents typically have relatively lower waterproof ratings, sometimes as low as 600 mm. However, it is more common to find ratings around 1200 mm, 1500 mm, or even 1800 mm, such as the Kelty Trail Ridge 6 tent. While these ratings may seem lower compared to other types of tents, they are usually sufficient for typical summer camping conditions where heavy rainfall is less likely.
The Issue of Seams:
When it comes to maintaining the waterproof integrity of a tent, the quality of seams plays a vital role. Seams are the areas where different panels of fabric are joined together, and if not properly addressed, they can become weak points where water can penetrate. Let’s explore two important aspects related to seams: untaped seams and the potential issues with condensation.
Untaped Seams:
Untaped seams refer to seams that have not been treated with any additional waterproofing measures. While some tent materials, like polyethylene floors, can be welded together to create a reliable waterproof seal, other fabrics require a different approach. In these cases, tape-sealed seams are commonly used to enhance the waterproofness of the tent.
Welding Used for Seams:
In the case of tents with polyethylene floors, welding is often employed as the most reliable method to create a waterproof seal. Welding involves using heat and pressure to fuse the seams of the material, creating a strong and watertight bond. This method ensures that the floor remains fully waterproof, even in wet and challenging conditions.
Issues with Condensation:
While making the fabric itself waterproof is important, it’s essential to consider the potential issues with condensation that may arise inside the tent. When the outside temperature is significantly different from the inside, condensation can form on the inner walls and ceiling of the tent. This moisture can make the interior damp, reducing overall comfort.
Conclusion
Understanding tent waterproof ratings is essential for selecting a suitable tent. Higher ratings are beneficial for tent floors due to abrasion and water pressure. Consider factors like quality seams and a full-coverage fly for enhanced waterproof integrity. Be mindful of condensation and opt for breathable materials when possible. With this knowledge, you can confidently choose a tent that will keep you dry and comfortable during your outdoor adventures.
