When choosing a hammock tarp, start with the obvious: it needs to keep you dry. Not all hammock tarps can do that reliably, sometimes because they are made in an inferior way from poor materials. But usually it’s because of the shape of the tarp itself. Another consideration is the ability of a tarp to protect from blowing rain and shed wind.
Hammock Tarp Shapes
Many hammock tarps on the market today are diamond-shaped. It’s easy to see why. First, they look really cool. Plus, it’s much less expensive to produce a diamond-shaped tarp because the triangular pieces allow the manufacturer to use much less fabric and save money.
The problem with diamond-shaped tarps is that they don’t protect a hammock very well, unless the rain happens to be falling straight down. When blowing rain begins, a hammock camper will find that a diamond-shaped tarp has little protection anywhere but over the middle of the hammock bed. The result is that the areas near the occupant’s head are far less protected.
Rectangular shaped tarps are also common, and protect better than diamond-shaped tarps. But rectangular tarps are also not created equal. These tarps have a tendency to flap noisily in the wind. This is caused because the outline of the hammock between the tie-out points are straight. Superior tarps are cut with curves between tie-out points to allow the hammock to shed wind and not keep you up all night listening to violent tarp flapping.
Materials for building hammock tarps
There are various fabrics and other materials used to make hammock tarps. The most popular is sil-nylon, a silicone impregnated or coated nylon fabric.
Sil-nylon is lighter than many other materials because the silicone coating itself is lighter than other coatings used to make nylon fabrics waterproof. In fact, it hardly adds any weight to the fabric at all. While much more expensive than polyurethane-coated fabrics, sil-nylon is definitely worth the price.
Another material sometimes used for hammock tarps is Cuben Fiber. Cuben Fiber is taken from the sailing and wind-surfing industry. It is a laminated fabric that is extremely lightweight. However, it is also more expensive than sil-nylon.
The current consensus is that sil-nylon makes more sense for hammock camping based on its price, its ability to be cut with catenary curves, and the fact that it blocks more light than cuben fiber. If a cuben fiber tarp is not cut to shed wind correctly, it is extremely noisy.
Clark, the inventor of the camping hammock, makes sil-nylon hammock tarps that are both protective and include wind-shedding catenary curves to help you sleep better. You also get velcro closures on each end of the hammock for ultimate protection in violent storms. Besides the tie out point on each side of the ridgeline, Clark tarps offer you three tie-out points on each side that create a reliable, waterproof shelter.
If you want to sleep well in a hammock, make sure you have the right hammock tarp, not just a cool tarp made on the cheap.