The Thermarest Slacker Hammock Sleeping pad is a 26-ounce self-inflating pad with an R-value of 2.1. Given its weight and size when rolled up, it’s best used for hammock car camping rather than backpacking. While not as sexy as a underquilt, it’s far less expensive, easy to deploy, and perfectly sufficient for warm weather hammock camping. The Slacker Hammock Pad can also be used as a comfortable sleeping pad when you want to go-to-ground and sleep in a tent, extending its utility.
Why do you need a sleeping pad or insulation underneath you in a hammock? The nighttime air is usually cooler than your body temperature. If you lie in a hammock without some sort of back insulation you’re likely to get cold at night, much like you would if you slept on bare ground without a sleeping pad. There are several types of hammock insulation solutions available to address this problem.
- Foam sleeping pads like a Thermarest Z-lite (inexpensive, bulky, awkward)
- Inflatable sleeping pads like the Thermarest XTherm (expensive, awkward)
- Down or synthetic underquilts like the Loco Libre Habanero or Hammock Gear Burrow (expensive, very comfortable)
- Hammock-specific inflatable sleeping pads like the Klymit Hammock V Pad and the Thermarest Slacker Sleeping Pad.
The Slacker Hammock Pad is fully symmetric and works well with simple camping hammocks or mosquito hammocks with integrated bug nets. It also works well if you can lie diagonally in your hammock, to get a flatter “lay,” instead of sleeping like a banana.
The pad is made of urethane foam with a durable 75 d polyester cover. Perforated channels in the foam prevent the pad from buckling when you lie on it in the confined space of a hammock. Thermarest obviously took a page out of the Klymit design playbook here, leaving gaps in the foam to reduce the weight of the pad and let it mold around your body in what they call an AirFrame design.
The Slacker Hammock Pad is 75 inches in length and 26 inches at its widest. The middle section of the pad is wide enough to insulate your butt and torso, while the tapered foot and head ends of the pad fit into the narrower ends of a gathered-end hammock. The ends taper to 16″ but have a width of 20″ where your shoulders would be positioned, providing insulation for your upper body and arms unless you have a very wide torso.
Technically self-inflating, the Slacker Hammock Pad does require a dozen breaths to fully inflate and has a standard Thermarest stick valve for this purpose. Deflation is a bit more challenging. Rolling up the pad, folding it in two, and sitting on it is the best way to compress it before stuffing it into its stuff sack. The included stuff sack can also serve double duty be used as a pillow or as a bolster under your knees to help prevent painful knee hyperextension, a common problem in shorter length, gathered-end hammocks.
The Slacker Hammock Pad provides good stability when you lie on it although it won’t flatten the curved shape of a camping hammock if you lie on it along the centerline. It does work well on diagonal lay hammocks though, especially ones that are fairly wide. It’s also exceptionally easy to use, unlike most cottage hammock underquilts which require configuring a complicated suspension system every time you use them.
While the Slacker Pad provides good three-season insulation for back sleepers and side sleepers, I wouldn’t recommend using it below 55-60 degrees at night given my experience using it and it’s relatively low R-value of 2.1 (which is the same as a Thermarest Zlite foam pad). Unfortunately, rating the temperature of under-insulation in hammocks is very subjective and there are enough individual differences between people that the only way to tell if a solution works for you is to test it out (and bring extra foam insulation along in case you get cold.)
What’s the value of the Thermarest Slacker Hammock Pad over a simple foam pad? Well it’s a heck of a lot more comfortable than a foam pad, it’s pre-shaped to fit in a gathered end hammock, wide enough to insulate your shoulders and arms, and it can serve dual use as a comfortable ground pad when you sleep in a tent. Given its size and weight at 26 oz, it is best used for camping and not backpacking, where a more compact, lighter weight insulation option is preferable.
Disclosure: Thermarest donated a pad for this review.SectionHiker is reader-supported. We only make money if you purchase a product through our affiliate links. Help us continue to test and write unsponsored and independent gear reviews, beginner FAQs, and free hiking guides.