The original design of the Garlington Insulator has been refined based on further testing and the suggestions of others. Like the original, the new Insulator consists of two components: a shell and insulation. The shell is a lightweight tarp and has been referred to as a ‘taco shell’ because it encapsulates the hammock body like a taco shell encapsulates a taco. The insulation can be anything with insulative value that can be held between the insulator shell and the hammock body.
The shell is an 8’x5’silicon-nylon tarp (finished size) with loops at the corners and a drawstring along one of the narrow sides.
5'x8'sil-nylon shell with corner loops and drawstring
Shell’s Foot End
Note the corner reinforcements and drawstring.
Insulation can be just about anything, but good results have been obtained using a crinkled, loosely rolled space blanket inside a large plastic bag, with a small amount of air trapped inside.
A crinkled space blanket is inserted into a large plastic trash bag.
Insulator bag assembled
A small amount of air is trapped inside the bag, and the end is tied off with a large rubber band.
Insulator bag installed
The insulator bag is inserted between the shell and the hammock body.
The tarp (shell) can be easily connected to a Speer hammock (or to a Hennessey Hammock if the side pulls are not used). Use the shell’s corner loops to fasten it to the hammock ridgeline, and use the drawstring to position the tarp after occupying the hammock.
First, tie the head end of the shell to the head end of the hammock using a short piece of cord looped around the hammock’s support line. The end of the shell should be tied even with the hammock body just before it flares out. Then, tie the foot end of the shell to the foot end of the hammock body in a similar manner. On the Speer Hammock, the long edge of the shell should align with the long edge of the unoccupied hammock with about the same amount of tension. On the Hennessey hammock the foot end should be tied more loosely, so that the middle of the shell’s footend can be pulled to within 6” of the reinforced area where the hammock fabric splits (to allow for bottom entry).
At the head end, gather all the excess shell material and tie it to the hammock’s support rope. At the foot end, tie a cord to the drawstring, and route it through a loop tied either to the ridgeline, or the hammock support rope.
Install your insulation, then get in the hammock. Pull the drawstring until the insulation touches the hammock bottom, then tie the drawstring to the ridgeline.
The Garlington Insulator on the Speer Hammock
As shown, the system weighs 12oz. The tarp weighs 8 oz and the space blanket air bag weights 4 oz.
This configuration has been tested overnight to a low of 40*F with good results. No pad was used inside the hammock. I was dressed in 100wt fleece (shirt, pants, socks) and used a Feathered Friends Rock Wren sleeping bag like a quilt. I tend to feel cold while sleeping, but this set up was comfortable.
I experienced a propensity for the airbag to slip ‘down hill’ during the night (toward the middle of the hammock). With the Speer Hammock, you can just reach out and reposition, but if this became annoying, you could run a short cord to the airbag to hold it in position.
On the Speer Hammock, the drawstring tension is adjusted once when the insulation is installed. On the Hennessey Hammock, the drawstring is adjusted each time the hammock is entered.
I think just using the shell will keep you comfortable down to about 60*F. Below that, you will need to add insulation. The airbag has been tested in low temperatures (~13*F) for short times (~2 hours); however, as you sleep, your metabolism slows so less heat is available to trap. I think extended stays at low temps for cold sleepers would require improved insulation.
If you don’t mind putting a pad inside the hammock, the Garlington Insulator with an additional pad has been tested down to 5*F with reasonable success; however, cold feet was a problem. (see Rick’s (aka geoflyfisher) test results in the version 1 writeup.)