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Using Trash Compactor Bags For Backpacking

Backpackers have been using trash compactor bags to line their backpacks for ages. A cheap compactor bag will keep your gear dry in pouring rain and terrible weather. How do you use trash compactor bags for backpacking? What size compactor bag is best for backpacks?

Line the inside of your backpack with a trash compactor to keep your gear dry in the rain. A standard 18 Gallon bag should be big enough for most backpacks. Go with unscented bags and remember that everything doesn’t have to stay dry.

Using trash compactor bags in your backpack will keep your gear dry. They’re cheaper than pack liners and work better than rain covers. Continue reading to learn how to use trash compactor bags for backpacking.

How to Use Trash Compactor Bags For Backpacking

I’ve been caught in more storms than I can count and unfortunately I wasn’t always prepared for the weather. A few years ago I made the switch from dedicated pack liners to compactor bags and I haven’t looked back.

They’re completely waterproof, cheap, durable, and easy to find. Just patch it up with duct tape on the trail and throw it out when you’re done. There’s really no reason to buy a dedicated pack liner.

  1. Take all the gear out of your pack before it rains.
  2. Place heavy/bulky gear that doesn’t need to stay dry in the bottom of your pack.
  3. Line the inside of your pack with the trash compactor bag.
  4. Load everything that needs to stay dry inside the trash compactor bag. You can always use a second bag if you can’t fit everything inside.
  5. Compactor bags can withstand a lot of abuse, but they will occasionally puncture. You can replace the bag or patch the hole with a little bit of duct tape.

You can save room in your compactor bag by keeping bulky gear in separate dry bags. My sleeping bag goes in a waterproof compression stuff sack that I keep at the top of my pack.

What Size Compactor Bag For Backpacks?

Before you head to the store for compactor bags you need to figure out what size compactor bag you actually need. Luckily, compactor bags come in one standard size (18 Gallons). Thankfully it’s the perfect size for most backpacks.

I’ve been using the Kirkland Brand Compactor Bags that you can find on Amazon or your local Wal Mart.If you need a larger size you can always go with a heavy duty contractor bag (these are huge) or flexible garbage bag.

Remember that everything doesn’t need to go inside the compactor bag. You only need to protect your clothes, food, sleeping bag, etc.

18 Gallon Compactor Bags Are Big Enough For Most Packs

Standard 18 gallon compactor bags (these are the ones I use) are big enough to line the inside of most packs. It’s actually 68-Liters and proportioned similarly to most packs. Even when you fold down the top it’s big enough to line the inside of my 65-Liter pack.

With larger packs just keep some of the stuff out that you don’t mind getting wet. There’s no need to put things like my rainsuit, tent, pack cover, and various dry sacks into the liner.

Unless you’re going on a serious hike this should be big enough. I normally end up cutting down the top of my bag so that I don’t have all that extra plastic scrunched up at the top.

You then just pack up your gear, twist the top and fold it down. Even in serious downpours the inside of my liner stayed bone dry and I never needed a pack cover.

Don’t Buy Scented Compactor Bags

I had a very hard time finding unscented compactor bags at my local grocery stores. After going to 3 or 4 different stores and calling around I finally found some at my local Ace Hardware.

Now I just save myself the hassle and buy a 5 pack of Hefty 18 Gallon Compactor Bags On Amazon. I’m sure that I could find them a little bit cheaper locally, but it’s not worth the hassle.

Not Everything Needs to Go Inside The Compactor Bag

Just remember that not everything needs to go inside the compactor bag. You really only need to protect your clothing, electronics, sleep system, etc from rain. Everything else can go on the bottom or top of your pack outside the compactor bag.

You can also use waterproof compression stuff sacks and dry bags to further protect gear that doesn’t fit inside the liner.

Larger Packs Try Contractor Bags and Flexible Garbage Bags

If you really decide that you need to have the entire inside of your pack lined you can try contractor bags and heavy-duty flexible garbage bags.

In the past I’ve used flexible garbage bags (Hefty Flexible Bags) and they worked really well on short trips(less than a week), but they do eventually tear. Just use a little bit of duct tape to fix tears whenever they arise.

Contractor bags should only be used with the biggest packs. These bags are absolutely huge; way bigger than any backpack will ever be. You can either fold the top down or cut off the extra plastic to customize the size of your bag.

Try ZPacks Pack Liners if Your Compactor Bag Keeps Tearing

Unfortunately some packs just don’t agree with compactor bags. The plastic hoop holders on one of my packs kept tearing into my compactor bag. With that pack I just use a couple of oversized dry sacks instead of the compactor bags.