Hammock length vs. tarp length?

[KBr00ks]

Seems like this is a question that has likely been answered here before, but I haven't found it, at least alone and not in other contexts: is there a good formula to determine the best tarp length to go with a certain hammock length?

Or to put it another way: I'm about to make a new hammock and considering going longer than my old 10-footer, but don't want to cause poor coverage with my current tarp. How do I figure out how long I can go?

Additional factors: I don't really want to get a new tarp (at least not in the short term), and I often set up in closely-spaced trees, so have appreciated the flexibility I do have.

(I need to measure my current tarp, as the old webpage of stats for that model is gone.)

[LowTech]

It seems that people usually set their hammock up w/ enough sag that the hammock ridgeline measures out at around 83% of the hammock length. So an 11' will have a ridgeline around 9'.

"Sent w/o me knowing"

[Phantom Grappler]

11 foot tarp ridgeline—11 foot hammock
11 foot hammock might have hammock ridgeline 109 inches.
Tarp is 132 inches
Hammock is 109 inches
132 minus 109 is 23 inches
Divide 23 by 2 and get 11 inches on each end of hammock to end of tarp.
But it never works that way for me!
Usually one or both ends of hammock do not get almost a whole foot of overhang.

My tarp has doors. I pitch my tarp ridgeline high, to be able to stand up under tarp.
When doors are closed, they angle inwards towards hammock. This contributes to less tarp overhang coverage of hammock. And usually hammock is not perfectly centered under tarp. Might have a half foot overhang on each end of hammock with ideal conditions!

For my 12 foot hammocks I use a tarp with a twelve foot ridgeline.

TominMN, great minds think alike! (Sometimes)

How I hang is not the be all and end all of hammocking. You are free to choose your own gear and rigging.
Good luck from somewhere deep in the Uwharries!

[TominMN]

Like above, about a foot overhang on each end is usually adequate. A longer rainfly obviously gives you more space under it but MAY occasionally limit hanging between two particular trees. Longer flies are obviously just a tad heavier and bulkier, all other things being equal.

[KBr00ks]

I currently have a little less than a foot (I think? w/o measuring) with my current setup. Don't really want any less! But given the hammock's sag, adding length to the flat hammock will not add the same amount of horizontal space taken by the whole setup... just wishing for an easy answer of "make X length and you'll be fine", but there never is, LOL.

[Bob-W]

If you go with the starting point of 83% sag for your hammock and aim for 300mm (1ft) extra coverage at either end then the nominal (I.e. Pre-sag) length of your hammock is the same as the ridge length of the tarp. There might be a cm or two difference.

So in metres (3.3m is approx 11ft)

3.3 x 0.83 = 2.739
2.739 + 0.6 = 3.339

So a total of 4cm longer. I have slightly more sag at a guess 82% which makes the difference just 9mm. My tarp and hammock are homemade and errors in hem width are probably greater than that!

[SilvrSurfr]

11 foot tarp ridgeline—11 foot hammock

I agree - the tarp should be as long as the hammock.

[KBr00ks]

So it really is that simple... tarp length = hammock length. A rule of thumb more than a formula but pretty much matches with experience and anecdotal evidence from this forum.

Now I have hard decisions to make...wasn't necessarily looking to go longer with my next hammock, but after all the advice on here that longer is better (including this recent thread), I feel like I should try it. But my tarp is only 125"...which happens to correspond pretty darn closely, according to this formula, to the length of my old hammock at 10' and change. (I cannot find the original scrap envelope on which I wrote down the final measurements after errors in hem width, but I recall it being 10'4" or thereabouts. More difficult to measure accurately now that it's busted.)

I may get some remnant fabric to try making and sleeping in an 11-footer just to see.

Besides not wanting to go to big due to closely- spaced trees, I also use the hammock setup for bikepacking, in which I'm concerned with limiting bulk as well as weight.

[LowTech]

I pack my 11' hammock (skinned), 12' tarp w/ doors (mesh skinned), fronkey bugnet, and UCR suspension + tree straps in a 13lt dry bag that goes in my handlebar harness when bikepacking. Sometimes I add some tent poles to the harness as well if I want to have an external pole mode config.
Neither my hammock or tarp are narrow or light weight. Just a reference point.

"Sent w/o me knowing"

[KBr00ks]

I guess realistically, another 10 square feet of fabric (between longer hammock and tarp) wouldn't take up that much room... but it's tough to go bigger, when I've gotten used to this -- hammock, bugnet, tarp, suspension, sleeping pad and rain jacket all fit in a 5L seatbag (the droopy camo thing in the back):

P1010088.jpg