In the first article of this series, we dealt with the hammock itself and the hammock suspension- the minimum requirements to actually hang in a hammock. In this article we will deal with the another component of a complete hammock system. While not critical to actually hanging in a hammock, insulation is necessary for a complete hammock system to be comfortable in varying conditions, such as cooler weather.
Insulation, especially if overnight temperatures are expected to fall below 70 (note: all temperatures mentioned in this article are in degrees, Fahrenheit), is necessary to prevent, at minimum, CBS (Cold Butt Syndrome) and in colder weather hypothermia or worse. When tent camping, most people use a pad, such as a closed cell foam pad or inflatable, or a hybrid of the two, and a sleeping bag. The pad may provide a modicum of comfort while laying on the hard ground (this point is debatable), but its main purpose is to insulate the camper’s body from the ground. Heat flows from hot-to-cold, and since the ground is colder than a human’s body (in most places, most times of the year) it will drain the heat from a person’s body faster than the heat can be replaced. Hence, insulation is needed. The sleeping bag also insulates heat lost from the individual into the surrounding air.
Because a hammocker is suspended in and surrounded by air, insulation is just as important when hammocking as it is when tenting. They also need insulation above and below. Just as we saw that there were different options in types of hammocks and suspensions, there are varying options in insulation as well.
If someone is already a tent camper and has decided to try hammocks, they probably already have a pad and sleeping bag. Some have tried to use just a sleeping bag, but the problem is that laying on the insulation compresses it, negating its insulating properties, just as it would if one were laying on the ground. Pads can be used as insulation in a hammock as well as on the ground. Simply lay the pad in the hammock and lie on it. Depending on preference and conditions, one can either use their sleeping bag as a cover or actually get in it and zip it up. There are many hammockers who use a pad and sleeping bag to camp in their hammocks successfully. I’ve never actually tried it, but I have camped with people who do it and have also read about it. Some common drawbacks/complaints seem to be 1. It is difficult to keep the pad in place through the night as the hammocker shifts positions. 2. The hammock is not quite as comfortable when a pad is inserted. 3. Because the pad doesn’t wrap around the hammocker’s sides, cold shoulders can become an issue as the hammock compresses the sleeping bag’s insulation in that area. Many hammockers use a sleeping bag/pad system because this gives them the option to “go to ground” (aka sleep in the dirt) if needed.
Whether or not to use a pad as insulation in a hammock system is entirely an individual decision. As I said in this article, individual customization is integral to hammock camping. In this area, however, the consensus seems to be that an under-quilt/top quilt insulation system is the most comfortable way to hang. Think of it like this: instead of a full sleeping bag, the under-quilt would be the bottom part of the bag which is suspended underneath your hammock insulating your backside, and the top half of the bag, your top-quilt, would cover you above. Additionally, no zipper is needed.
The first under-quilts Cathy and I used were DIY (Do-It-Yourself) jobs made from military surplus poncho liners, also known as “PLUQs” (Poncho Liner Under Quilt). We added shock cord and hardware to them so that we could suspend them underneath our hammocks, and they really did work well. We used this video (Thanks, KDawgCrazy!) as a guide. They’re fairly lightweight and I’d guesstimate that they would be effective down to the low 50’s (depending on how warm or cold of a sleeper you are). An easy way to extend/supplement their insulating properties is to add an appropriate sized piece of Reflectix, or like we did, a truck-sized windshield reflector. Other options for the same temperature ranges include modifying a Costco down throw-blanket, which can also be purchased relatively inexpensively.
There are also commercially available under-quilts, both synthetic and down insulated. Synthetics, although less expensive, are heavier and bulkier than their down counterparts. Down is substantially more expensive, but its insulating properties are unequaled, it is much lighter and compresses much more, saving critical weight and space in a backpacker’s pack.
Cathy and I, after careful consideration, decided to purchase a set of down quilts for each of us. They were expensive, but considering all of these previously mentioned factors it seemed like the most preferable option. In the following video, I will show you the quilts and their features, and how they’re used when hammocking.
Here is a video detailing our “pre-down” insulating equipment and discussion on down alternatives.
Keep in mind, the amount of insulation needed will vary from one person to the next. At the same temperature, I may be comfortable and Cathy may be cold even though we are using the practically identical equipment. Get a feel for how you sleep and what works best for you!
In our next article we will discuss protection from wind and rain (or snow, as the case may be).