Anyone who has spent the night in a hammock knows the problem: it’s cold from underneath! Despite a blanket or sleeping bag, you just freeze. Your shoulders, back and bottom cool down. There are two solutions that can help you sleep warm and relaxed in your hammock.
The problem: Why is it cold from below in the hammock?
What is the advantage of hammocks on a hot day turns into a disadvantage at night. In the hammock, no insulating air cushion can build up between the back and the hammock. The body weight presses the clothing layers or the sleeping bag tightly against the hammock and the wind blows under the hammock. It is the perfect cooling: no insulation and the wind simply blows away the heat radiated from the body.
Two solutions of how to stay warm in the hammock
There is a simple way to combat the cold: an insulating layer is needed to protect the body from the cold from below. Either between the body and the hammock or between the hammock and the surroundings.
1. Use an underquilt or underblanket
This is the most comfortable type. An underquilt, sometimes also called an underblanket, hangs like a second hammock below the actual hammock. There it protects against the cold from below without affecting the comfort of lying down. In the meantime I have underquilt by OneTigris* for the summer and the underblanket by Snugpak for the colder seasons.
Protection from the cold: Underquilt insulates the hammock from below
Properly attached, an insulating air cushion forms between the Underquilt and the hammock. My underquilt from Snugpack has the shape of a hammock and covers almost the entire hammock. This also protects the feet and head from the cold. But there are also smaller underquilts that only keep part of the hammock warm. In terms of pack size, an underquilt is as big as a small sleeping bag.
The most comfortable protection against the cold for the hammock
As a counterpart to the underquilt, there is also the top quilt. This protects the body from the cold from above. Here, however, I always use a sleeping bag. But basically, the underquilt and the top quilt are a sleeping bag cut open, in which a hammock hangs.
2. Sleeping pad in the hammock
The simpler solution is a classic sleeping mat. It goes between the body and the hammock. Depending on the type of sleeping pad, it provides different levels of protection against the cold.
Disadvantages of an speeping pad in the hammock as protection against the cold
The sleeping pad slips easily in the hammock
My sleeping pad often slipped when I turned around in the hammock. The shoulder, side or half of the buttocks would cool down. The pad can be pushed back under the body, but it’s an act every time. I also didn’t like waking up several times at night because of the cold. To avoid this, professional camping hammocks have separate slide-in compartments for sleeping pads. That is the case with DD Frontline hammock, for example.
Cold shoulders despite sleeping pad
Another problem is the shoulder area. Small movements during sleep cause a shoulder to slip off the sleeping mat or press against one side of the hammock. Then there is the original problem again: the sleeping bag is compressed at that point and the warming air cushion for insulation escapes. To prevent this, there are special sleeping pads for hammocks. The Klymit V* sleeping mat has side wings in the shoulder area and in the foot zone. This way, feet and shoulders remain surrounded by the sleeping pad all the time.
Protection from the cold from below: Underquilt or sleeping pad – My recommendation!
In terms of lying comfort, the Underquilt is clearly the better choice for me. Properly hung up, it is not noticeable in the hammock – it feels like being without protection against the cold and yet it is still comfortably warm. If an extra piece of luggage is not a problem, then the Underquilt is there.
The situation is different for ultralight tours, where every gram counts. Then a sleeping pad is the better choice. If in doubt, I can sleep on it on the ground and it protects me from the cold from below. Apart from that, the Underquilt is just a strangely cut blanket that is no good as an insulating mat on the ground.