Pack Cover Necessary

A good pack liner — properly closed up — will keep 100% of the rain out — and protect your contents in case of a stream-crossing or canoeing mishap.

A pack cover gives partial rain protection (although good enough most of the time) but no protection in case of pack dunking.

I've been using 2-mil "contractor bags" to great satisfaction. They're cheap, weighs just 2.6 oz. and they have protected me from both hours of hiking in the rain as well as a full-on river dunking.

Finally, you should know that the above contractor bags are almost twice as strong as "heavy duty" yard and garden bags — which only have around 1-mil rating.

Under most conditions, I think you will be fine with the Pinnacle and effective use of liners. Just don't fill the liners until they are bursting; make sure you have some room in them to get an effective seal at the closure and occasionally inspect them for holes. You can double the protection with a pack cover if you are expecting a violent cloudburst or something of that nature, but you should be fine using DriDucks for your body (I love my Propore) and liners with your in-pack gear. I have used both covers and liners and both have actually worked well for me; I usually just use liners, however.

Check out this article by Jim Wood; he discusses such issue with great detail:
http://jwbasecamp.com/Articles/DryGear/index.html

Hope it helps!

I have walked for days with my jam2 in all types of rain. I had a poncho that was used as a pack cover. I use a pack liner. The dyneema will allow water to come through in small amounts, but with the pack liner everything else stays perfectly dry. And as one person posted a dunking in a stream also has great potential to wet your gear. I should'nt have, but crossed a swollen stream in the Smoky Mountains last fall. My feet were swept out from under me and I went down. I was rolled through two rapaids and ended up bobbing around like a watermelon in a pool at the bottom. I swam to the side and got out. I Shook off and started digging in my pack hoping I had some dry clothes to wear– and thanks to the pack liner, I did. I have been used contractor bags (heavy, but tough), comPACTor bags (nice), and am now using Glad Forceflex (strong and light).

The suggestion for contractor weight bags is an excellent one. I've never had gear get wet when placed in one with the top rolled closed. GoLite, or any other Dyneema gridstop product is not waterproof. It's only about 1/10 Dyneema so the remaining 90% is not waterproof. Even with a full Dyneema pack the stitching in the sewn seams would have to be sealed to make it absolutely waterproof. I haven't yet decided to seam seal mine.

I have a GIANT ziploc bag that my grandma gave me for christmas. It poured on christmas day so I went ahead and threw some clothes in it and chucked it in a puddle. left it overnight, dry shirts in the morning.

One thing to consider about pack covers is will the pack cover even stay on. Most pack covers are meant to cinch around the pack with a cord or elastic. The top and bottom of most ultralight packs does not extend above and below where the shoulder straps and hip belt attach and the pack cover will not stay on without some other method of attachment. You could make cuts on both sides of the bottom of the pack cover for the hip belt to pass through but it may not stay attached around the top either. A pack liner is much lighter and won't blow off in a strong wind or when going through brush.

I am a huge advocate of putting slits into a garbage bag, and using this as a pack cover. Your entire pack is covered, except for the straps which protrude through the slits in the bag. This is my favorite method because: 1) its easier to go through your belongings in the pack when a pack liner wouldn't be necessary (ie no rain); 2) it keeps the back of the pack dry. I like the back of the pack to stay dry since I use my pack for ground insulation in addition to a Torso length sleeping pad. If it were wet, that wouldn't be good for my down bag now would it?

I'm glad that people here mentioned using a liner when fords are an issue. This is a great point, and I think this will convince me to use a liner instead thru the High Sierra this spring on my PCT thruhike. The rest of the trip I'll probably ditch it to save a few ounces, and instead rely on my ponchotarp.

So: if fords aren't an issue on your hike, go for a pack cover. If you will be doing sketchy fords…pack liner.

I use Sea to Summit Ultra-sil dry bags to organize the stuff I don't want to get wet – clothes, first aid/fire kit, quilt come to mind – and dispense with the cover.

It hasn't been an issue, and it bugs me to carry a cover when most of the time it isn't raining.

I actually hike with my cover on my pack all the time. I figure why place it in your pack when it fits just as well outside? The pack cover dose a nice job protecting my pack from abuse and rain.

I also use my pack cover when in camp. I remove my pack and place the pack cover on the back site so it is covering the shoulder straps, hip belt and back panel. I am now able to lay my pack down on the ground with easy access to it's contents (front loading pack) without getting it dirty or muddy.

I use my pack cover for more than just rain, like Chad describes. Might as well put it to work. I also line my pack, but I prefer a pack cover for serious rain to avoid the pack absorbing water and adding weight.

Which leads me to a question I've had for a long time about pack fabric. Why aren't packs made of waterproof fabric to begin with? The fabric doesn't need to be breathable – just strong, lightweight, and waterproof. No such combination?