Dry Bags vs Stuff Sacks: What Should You Use for Ultralight Backpacking?

Quick Answer

For ultralight backpacking, use dry bags for items that must stay dry, like sleep gear and electronics, and stuff sacks for items that can tolerate some moisture, such as clothing and food. Dry bags offer waterproof protection but are heavier and bulkier; stuff sacks are lighter and more compressible but not fully waterproof.

When you're shaving ounces off your pack, every piece of gear counts. One common question is whether to use dry bags or stuff sacks for organizing your backpack. Both have their place, but understanding the trade-offs can help you build an efficient packing system.

In this comparison, we'll look at the differences between dry bags and stuff sacks, focusing on waterproofing, weight, and practical use. We'll also highlight some Zpacks options that fit well into an ultralight setup.

What Are Dry Bags and Stuff Sacks?

Dry bags are fully waterproof containers, typically made from coated fabrics like Dyneema® or PVC, with roll-top or zip closures. They keep contents completely dry even when submerged. Stuff sacks, on the other hand, are usually made from lightweight nylon or polyester and are not waterproof. They are designed to compress and organize gear, but they won't protect against rain or water crossings.

In ultralight backpacking, the choice often comes down to how much you value waterproofing versus weight savings. Dry bags tend to weigh more because of the waterproof materials and closures, while stuff sacks are lighter and more flexible. However, modern ultralight dry bags, like those made from Dyneema®, can be surprisingly light.

• Dry bags: waterproof, heavier, bulkier, ideal for critical gear.
• Stuff sacks: lightweight, compressible, not waterproof, good for non-critical items.

Waterproofing: Why It Matters

The primary job of a dry bag is to keep water out. Whether you're fording a stream, caught in a downpour, or your pack falls in a lake, a dry bag ensures your sleeping bag, down jacket, or electronics stay dry. This is non-negotiable for gear that loses insulation when wet.

Stuff sacks offer no waterproof protection. If you're in a wet climate or expect water crossings, you'll need to line your pack with a trash compactor bag or use dry bags for vulnerable items. The trade-off is weight and space: dry bags are heavier and don't compress as well as stuff sacks.

• Use dry bags for items that must stay dry: sleeping bags, quilts, down clothing, electronics.
• Use stuff sacks for items that can get damp: extra clothing, food, camp shoes.

Weight and Packability

In ultralight circles, every gram counts. Stuff sacks are generally lighter because they use thinner, non-waterproof materials. They also compress gear more effectively, allowing you to fit more in your pack. Dry bags, even ultralight ones, have heavier fabrics and closures that add weight.

However, some ultralight dry bags are designed to be as light as possible. For example, Zpacks uses Dyneema® Composite Fabric, which is both lightweight and durable. This can narrow the weight gap, but dry bags still tend to be less compressible than stuff sacks.

• Weigh the cost of waterproofing against the weight penalty.
• Consider using a hybrid approach: a waterproof pack liner and stuff sacks for organization.

Organization and Access

Stuff sacks often come in various sizes and colors, making it easy to organize your gear. You can assign a sack for cooking gear, another for clothes, and so on. This speeds up packing and finding items in your pack.

Dry bags also come in different sizes and can be color-coded, but they are typically more rigid and take up more space. Some dry bags, like the Zpacks Tall Dry Bag, are long and skinny, designed to fit in side pockets or lash to the outside of your pack, which can be handy for items you need to access quickly.

• Use color coding to quickly identify contents.
• Long, skinny dry bags can be lashed to the outside for easy access.

Trade-Offs to Consider

• Waterproofing vs. Weight: Dry bags provide peace of mind but add weight. Stuff sacks are lighter but require a pack liner if rain is likely. If you hike in wet conditions, the extra ounces for a dry bag are worth it.
• Compression vs. Protection: Stuff sacks compress gear into smaller volumes, but dry bags maintain a fixed shape, which can waste space. For bulky items like sleeping bags, consider a compression sack if waterproofing isn't needed.
• Durability vs. Flexibility: Dry bags made from Dyneema® are tough and puncture-resistant, but they are less flexible than soft stuff sacks. Choose based on the terrain; rocky environments favor tougher materials.

Zpacks Options for Ultralight Packing

• Tall Dry Bag: This dry bag is long and skinny allowing it to be securely lashed to your pack’s base straps, or stored standing vertically in a side pocket. Put less critical items like your tent, sleeping pad, rain gear, today’s food, or town clothes on the outside. This design maximizes space in your pack and gives you quick access to items you might need during the day without unpacking everything.
• Rock Stuff Sack: Constructed from ultralight but durable 1.6 oz/sqyd Dyneema® Composite Fabric to resist abrasion and punctures. This is also a great way to store cord. A stuff sack made from Dyneema® offers durability and weather resistance, making it a versatile choice for organizing gear that doesn't need full waterproofing.

How to Choose What's Right for You

Best for

• Hikers who need to keep sleeping gear dry in wet climates or during water crossings.
• Ultralight backpackers who prioritize organization and quick access to gear with color-coded dry bags.

Not for

• Minimalists who want to save weight and are comfortable using a pack liner and stuff sacks.
• Those who don't expect heavy rain or water exposure and prefer maximum compressibility.

In the end, both dry bags and stuff sacks have a role in an ultralight packing system. Use dry bags for your critical, water-sensitive gear, and stuff sacks for everything else. This balanced approach keeps your pack light, organized, and ready for whatever the trail throws at you.