In 2015, I rode the Continental Divide carrying the Big Agnes UL Copper Spur 2. In 2016, I was looking to bikepack more technical terrain, and I wanted to lighten my load without sacrificing warmth. (I was constantly cold on the Divide, which I ameliorated by using a SOL emergency blanket on top of my 45 degree synthetic sleeping bag every night after I left Wyoming.)
Since I got my hands on the Mountain Hardwear Dry.Q Bivy Sack, I’ve ridden the Kokopelli Trail, a handful of Colorado Front Range overnighters, and the White Rim Trail. It’s now been almost exactly a year since I got the bivy, and I finally feel I’ve slept out with it enough to know how it performs.
This is a medium-weight, relatively affordable bivy that performs best in semi-arid, windy, or moderately cold conditions. A noticeable amount of condensation will accumulate between your sleeping bag and the bivy, and I would not recommend this to someone expecting very cold weather as it may freeze. I would also not recommend this if you are expecting a lot of rain as the cinch closure around the head box still leaves space for rain to enter. I would recommend this bag to someone who is looking for an affordable, durable bivy, and expects to encounter cold to mild temperatures, wind, or light rain.
This bivy does not do an exceptional job of letting body-generated moisture escape. I have camped in the high desert with this bivy and the Colorado forests, and my sleeping bag was consistently damp by the morning. The dampness was always relegated to the outside of the sleeping bag, and I always stayed dry and warm. However, I would need to pack my sleeping bag away damp. Additionally, moisture would condense on the inside of the bivy especially near the head box. While it didn’t prevent me from sleeping, it wasn’t pleasant to wake up to every morning. Then again, a person who sleeps in a bivy typically isn’t in it for the pleasantries. I would be wary if you want to take this bivy in very cold places, as this condensation layer may turn into ice.
The folks at Mountain Hardwear Customer Care indicated that the bivy doesn’t have a direct breathability rating. For your reference, the methods used to test breathability are not as widely standardized as that for waterproofing. For a great reference on breathability and waterproofing, check out this page from Evo.
I found this bag to be exceptionally good at retaining body heat, even in windy conditions. I’ve slept out in the open in the high desert as well as the woods, and I’ve never been cold. I have stayed warm with my 45 degree synthetic bag on 30-45 degree nights and with my 15 degree down sleeping bag on 10-30 degree nights.
The Dry.Q Bivy features zippers and seams that are taped for water proofing. However, the opening for your face is a closure that – when fully cinched down – still leaves about a 3” diameter hole. If it were raining hard, you might need to roll over to avoid getting water in the bivy.
Mountain Hardware told us that the water proofing is “rated to be at least 10,000mm of pressure”. This roughly translates into withstanding average rain at a light pressure.
I hoped to test this quality more empirically. However, living and adventuring in the relatively dry climates of Colorado and Utah, I felt that the “Dry” part of the Dry.Q wasn’t adequately tested. So I came up with a “lab” experiment.
I felt it wasn’t fair to try and replicate a water-column test, because I couldn’t guarantee experimental rigor. However, I did feel that sticking the bivy under the rain-like shower head was a pretty good way to see how permeable the material was.
Everyone knows that you never wear a light blue button down if you think you’re going to sweat… because it shows, immediately. So, I stuck my fancy button down in the bivy, tightly wrapped the head opening, and put the bivy on the shower floor.
After 15 minutes of direct showering, my light blue shirt came out completely dry.
Unsatisfied with this successful test, I put the shirt back in the bivy, turned the shower on for an additional 5 minutes, and then left a pool of water standing on/around the bivy for the rest of the night. Indeed, water permeated the bivy to the point where I had to dump it out the next morning. Herein lies proof that the bivy is not made of rubber, and that you won’t stay dry if water pools around you while you sleep.
The bivy packs down fairly small, but not as small as some of the other lightweight bivys out there. It measures about 3” in diameter and about 4” in length. However, I tend to stuff a bivy around other things in my bikepacking bags, which it does very well. It weighs in at 11.5 oz.
Durability and Ease of Use
After using this as a ground cloth and a bivy for a year (over about 20 days of sleeping out), I’ve not seen any wear or tear. The material seems highly durable, and is easy to clean. The zippers are particularly good at catching the material and getting stuck, which is a downside that can be avoided with a more careful user action. The zipper pulls have a bit of reflective material so the pulls are easy to find at night. The cinch action is what you get with a typical one-sided drawcord; easy at first, harder when it gets tight. Overall though, no complaints on the drawcord.
As this review is a year old, Mountain Hardwear will undoubtably come out with a new bivy in the future. As of this writing, you can now buy the Dry.Q for $89 instead of the original $189. For future reference, here’s a breakdown of the materials used, so you might compare with any future iterations:
Fabric Topside Upper (black, near the head box): AirShield™ Nylon Ripstop
Fabric Topside Lower (black, chest and below): 100% nylon
Fabric Floor (orange): 40D Nylon Ripstop 1500mm Ester Type PU/SIL FR
Bag Shell (white interior): Dry.Q® 2L Ripstop
Water proofing: At least 10,000mm, but no designated threshold