Tarps vs. Overcovers

[Bushwhacker]

So I've done a few google searches on this site (added query site:.hammockforums.net) to try to understand overcovers and tarps. It seems like:

- Overcover's primary protection isn't to repel water, but to preserve warmth.
- Making overcovers out of something that is really waterproof, like cuben fiber, is not common enough to come up in searches.
- For some reason people avoid laying their tarps directly on the ridge line of the hammock. If it's truly a waterproof material, I don't understand why people don't do this. If you have a small tarp you can put it directly on, if it's bigger, why not just cut slits in the tarp?

- Side question: Do hennessey asym tarps lie directly on the ridgeline?

I feel like the best solution to the ultra-lighters out there may be to get an asymmetrical tarp and pitch it directly on the hammock ridgeline, which would save on guylines. If it's too warm out they can pitch pull out guylines further out, and in cooler weather, they can wrap the tarp closer around the hammock.

[pgibson]

Tarps are made from waterproof materials. Top or over covers are made normally from breathable fabrics. The reason to not put the tarp directly on the hammock is so that air flow can move the humid moisture that you give off can evaporate and be moved out of your shelter system. If you put the tarp directly on the hammock in an attempt to seal in heat you would also seal in the condensation which would soon get your sleep system wet. Top covers are made from breathable fabrics so that moisture can pass though the fabric working to mitigate moisture build up on your insulation and hammock.

[Bushwhacker]

Tarps are made from waterproof materials. Top or over covers are made normally from breathable fabrics. The reason to not put the tarp directly on the hammock is so that air flow can move the humid moisture that you give off can evaporate and be moved out of your shelter system. If you put the tarp directly on the hammock in an attempt to seal in heat you would also seal in the condensation which would soon get your sleep system wet. Top covers are made from breathable fabrics so that moisture can pass though the fabric working to mitigate moisture build up on your insulation and hammock.

I understand the humidity & condensation argument, but if you only have a thin 1.1 nylon hammock, it would surely be breathable enough to counteract a cf tarp lying directly above, right? And as I said, you can pitch the sides of the tarp higher up if you need more breathability. Is there something I'm missing?

[pgibson]

You would be very surprised at how much condensation will form on everything and how quickly. Condensation can under the right conditions form on bug net....so no don't expect a 1.1 nylon to breath out all moisture well enough to keep condensation from forming on a tarp that is in contact with the top of the hammock.

[nothermark]

I understand the humidity & condensation argument, but if you only have a thin 1.1 nylon hammock, it would surely be breathable enough to counteract a cf tarp lying directly above, right? And as I said, you can pitch the sides of the tarp higher up if you need more breathability. Is there something I'm missing?

Wrong. Most of the moisture moves up because it is warm air expelled as you breath. In the mean time your hammock is covered with your pad blocking moisture or you a loading downward moving moisture into your bottom quilt.

Hennessy attaches the smaller tarp to the hang lines as is the ridge line. They are not attached to each other. The tarp often ends up touching the ridge line but the net is in between.

[wisenber]

I understand the humidity & condensation argument, but if you only have a thin 1.1 nylon hammock, it would surely be breathable enough to counteract a cf tarp lying directly above, right? And as I said, you can pitch the sides of the tarp higher up if you need more breathability. Is there something I'm missing?

Not a chance. The majority of moisture moves upward and is trapped under a tarp if enough ventilation is not present. With the tarp close to your face, expect rain underneath in warm weather and snow under your tarp when it gets cold. If you want to try it out without a tarp, just cut a garbage bag and suspend it on your hammock ridgeline above your head and stay in it overnight.

[wisenber]

I feel like the best solution to the ultra-lighters out there may be to get an asymmetrical tarp and pitch it directly on the hammock ridgeline, which would save on guylines. If it's too warm out they can pitch pull out guylines further out, and in cooler weather, they can wrap the tarp closer around the hammock.

Generally speaking, a small asym tarp lets one choose which side to get wet.

[Bushwhacker]

Generally speaking, a small asym tarp lets one choose which side to get wet.

I can only assume that you had a bad experience with an asym. Could you please elucidate me?

[wisenber]

I can only assume that you had a bad experience with an asym. Could you please elucidate me?

Asym tarps by their very nature have one side protected better than the other. The primary way of offsetting this shortcoming is by setting the hammock closer to the tarp. So the tarp can be set at a standard pitch or low to the hammock. If rain with any wind arrives, either your head or your feet will get wet with a standard pitch. If the tarp is set close to the hammock, condensation will make all of you wet. Been there and done that repeatedly. Now if there is next to no chance of rain (i.e. might not even need a tarp), it's a serviceable option.

[hawghangar]

Many also like convenience of setting up and tensioning their tarp separate from their hammock. Provides maximum protection of gear during setup, and much easier to maintain tension.