Is Osprey rain cover waterproof?

An Osprey rain cover is designed to be waterproof and provide protection for your backpack and gear in wet weather conditions. However, the level of waterproofness can vary between specific Osprey rain cover models. In this article, we’ll take an in-depth look at whether Osprey rain covers are truly waterproof.

The Purpose of an Osprey Rain Cover

An Osprey rain cover is meant to keep the contents of your backpack dry in rain, snow, and wet conditions. Rain covers are useful for protecting your extra layers, electronics, food, and other gear when you’re hiking, backpacking, or traveling. The cover fits over the entire backpack and cinches at the bottom for a secure fit.

Here are the key benefits of using an Osprey rain cover:

• Keeps your pack and gear dry in wet weather
• Lightweight and compact – easily packs into your bag when not in use
• Durable material withstands rugged use
• Adjustable cordlock at hem for a snug and secure fit over pack
• Reflective graphics provide visibility

Having a rain cover for your pack allows you to adventure in rainy conditions while keeping your belongings protected and dry inside. However, for the cover to be effective, it needs to prevent water from seeping through.

Osprey Rain Cover Fabrics

Osprey constructs their rain covers from different types of water-resistant fabrics, depending on the specific model. Some of the common fabrics used include:

• Nylon: A very common material used for rain covers and outdoor gear. Nylon is lightweight, packable, and dries quickly. The level of water resistance depends on the denier (thread thickness).
• Silnylon: A more advanced, ultra-lightweight nylon fabric treated with silicone for enhanced water resistance and durability.
• Cuben fiber: An even more waterproof synthetic fabric made of laminated polyethylene sheets. However, Cuben is more expensive.

Some Osprey rain covers also have a polyurethane coating or DWR (durable water repellent) chemical treatment on the fabric to improve water beading and resistance. However, coatings can wear off over time.

Key Factors That Impact Waterproofness

There are several variables that determine how effectively an Osprey rain cover will keep water out of your pack:

• Fabric density: Densely woven fabrics with a higher denier count are more water resistant. Lighter, more porous materials let more moisture seep through.
• Fabric coating: PU or silicone coatings on the fabric help prevent water absorption and penetration. Uncoated covers absorb more moisture.
• Seam construction: Fully taped seams block water ingress better than stitched seams. Untaped seams are most prone to leaking.
• Fit over pack: A tight, snug fit over the pack prevents rain running down the material. A loose cover can let water in around openings.
• Condition of fabric: Brand new covers offer maximum waterproofness, while older worn fabrics lose their protective properties over time.

Considering these factors, not all Osprey rain covers provide the same level of water resistance. More expensive models made with advanced fabrics tend to offer better waterproofness.

Testing Osprey Rain Cover Waterproofness

To evaluate the real-world waterproof performance of a rain cover, it needs to be tested in wet conditions. There are a few methods to test waterproofness:

• Shower test: Spray the cover with a hose or showerhead for several minutes and check if any moisture is leaking through onto the pack.
• Submersion test: Fully submerge the rain cover in water for a period of time and assess internal and external moisture.
• Wet weather test: Use the cover in actual rain, snow or heavy mist conditions while hiking or backpacking.

Ideally, minimal water should permeate the fabric after extended wet testing. A totally “waterproof” cover allows no moisture ingress. However, cheaper models often leak to some degree when subjected to heavy water exposure.

Osprey Rain Cover Models Comparison

Here is a comparison of a few popular Osprey rain cover models and their relative waterproofness based on user reviews and product details:

*Waterproof rating is based on a 1 to 5 scale, with 5 being completely waterproof and 1 allowing significant water ingress.

This table shows how water resistance improves with lighter, more densely woven fabrics, advanced seam sealing, and high-end materials like Cuben fiber. Note that sizing the cover properly for your pack model also affects the waterproof rating.

Tips for Improving Osprey Rain Cover Waterproofness

If your Osprey rain cover seems to leak or soak through in very wet conditions, here are some tips to enhance waterproof performance:

• Treat the fabric with a waterproofing spray like Nikwax TX Direct to improve moisture beading.
• Seal any leaking seams or fabric openings with waterproof seam sealant.
• Tighten all cord locks and openings for a snug, close fit over your pack.
• Use a pack liner or dry bag inside your backpack for extra water protection.
• Upgrade to a more technical rain cover model made with advanced waterproof fabrics.

With proper maintenance and preparation, even budget Osprey rain covers can be quite effective at keeping your gear dry in wet weather hiking and backpacking trips.

Conclusion

In summary, Osprey rain covers provide varied levels of waterproofness depending on the specific model. Less expensive covers often leak when subjected to heavy rain or submersion but can handle light showers. More technical Osprey covers with coated fabrics, taped seams and high-end materials like Cuben fiber offer excellent water resistance and true waterproofing.

To ensure your gear stays dry, it’s best to choose a rain cover with proven waterproof construction and perform your own wet weather testing. Supplementing the cover with a pack liner and proper maintenance will further improve effectiveness. While an Osprey rain cover may not be 100% waterproof, it certainly supplies a useful level of protection from the elements when you need it.