How to Use a Dry Bag as a Pack Cover for Rain
By Sea to Summit | Outdoor Gear To Equip & Inspire | Published: 2026-10-30
Category: How-to Guides
Learn how to turn a dry bag into an effective pack cover for rain, including step-by-step instructions and tips for ultralight backpacking.
Quick Answer
Yes, you can use a dry bag as a pack cover for rain. Choose a dry bag that fits over your backpack, secure it with compression straps or a sling, and ensure the closure is tight to keep water out.
Why Use a Dry Bag as a Pack Cover?
A dry bag is typically more waterproof than a standard pack cover because it uses a roll-top or zippered closure that seals completely. It also doubles as a storage solution for wet items or as a camp pillow. The trade-off is that a dry bag may not cover the entire backpack, leaving the shoulder straps and hip belt exposed. For ultralight backpackers, this is often acceptable because the main compartment stays dry.
How to Use a Dry Bag as a Pack Cover
- Choose the Right Size Dry Bag: Select a dry bag that is slightly larger than your backpack's main compartment. A 20-30 liter dry bag works for most daypacks; 35-50 liters for multi-day packs. The dry bag should fit snugly over the pack's body without leaving large gaps. Too small a dry bag will not cover the top of your pack; too large will be bulky and may slip off.
- Prepare Your Backpack: Remove the shoulder straps and hip belt from your backpack if possible, or loosen them so the dry bag can slide over the pack. Alternatively, stuff the backpack into the dry bag if it is small enough. Ensure the backpack's contents are already in a waterproof stuff sack or liner for redundancy. Leaving straps attached can cause the dry bag to bunch up and create gaps.
- Secure the Dry Bag: Place the dry bag over the top of the backpack and pull it down until the pack's main body is covered. Use the dry bag's compression straps or a separate strap (like the Dry Bag Sling) to cinch it tight around the pack. Roll the dry bag's closure at the top and clip it shut. If the dry bag slips, use a bungee cord or a gear tie to secure it to the pack's frame.
- Check for Gaps and Adjust: Inspect the fit: there should be no exposed fabric on the top or sides of the main compartment. If your backpack has a hydration port or daisy chains, tuck them inside or seal them with tape. For heavy rain, use a poncho (like the Nylon Tarp Poncho) over the entire setup for extra coverage. A common mistake is leaving the shoulder straps exposed—water can wick through the strap webbing into the pack.
Related Gear
- Dry Bag Sling (Like New): The detachable Dry Bag Sling converts certain compatible dry bags to a hands-free tote with a comfortable 3D mesh shoulder pad for loads up to 9kg. If your dry bag has a base attachment point, the Dry Bag Sling lets you carry it over your shoulder when not in use as a pack cover, adding versatility without extra weight.
Dry Bag Sling (Like New) - Nylon Tarp Poncho (Like New): The Nylon Tarp-Poncho is a seam-taped 70D nylon poncho that can double as a tarp shelter when not worn. For full coverage in heavy rain, pair your dry bag pack cover with this poncho to keep both your backpack and body dry, and use the poncho as a shelter at camp.
Nylon Tarp Poncho (Like New)
