Hennessy Hammock Weathershield Questions

**Peter_pan** · 12-13-2006, 10:52

JJ ... True it will be better than silnyl.

Headchange4u.... give it a try... you may like it.

Pan

**headchange4u** · 12-13-2006, 22:46

Quick and dirty HH top cover:

Made from 1.9oz untreated ripstop nylon with a draw string that runs the perimenter of the cover. I did a quick set up and tested it in the back yard. The cover fits the hammock great. When you pull the draw string the edges of the cover hug the hammock. Couldn't have worked out better.

I put the cover on and got inside the hammock. I noticed with my weight there is a very small slit that opens up right above my head and at my feet. This works for getting in air so I'm not going for a hole in the top right now. It was slightly breezy tonight and the cover stopped the wind. After lying in the hammock for about 20 minutes I could tell a VERY noticable difference in the air temp inside the hammock and outside.

Although I have not given it any real world tests, I am very happy at this point on how it performs.

**slowhike** · 12-13-2006, 22:56

that`s bound to make a differance... in a good way. & i`ll bet it weighs near nothing.

**Peter_pan** · 12-14-2006, 08:54

Test it some and post the results....please be sure to include the test conditions, temp, relative humidity etc...

Pan

**headchange4u** · 12-14-2006, 21:30

I got a chance to take some pics today of the top cover installed on my HH. Here's a couple of shots:
http://www.hammockforums.net/gallery...r&imageuser=27
http://www.hammockforums.net/gallery...r&imageuser=27

I tighten the draw cord and tie it off to my biner:
http://www.hammockforums.net/gallery...r&imageuser=27

Here'sa some shots from the inside. The first pic shows the gap that opens up at my feet when lying in the hammock. The second pic is the gap above my head for breathing.
http://www.hammockforums.net/gallery...r&imageuser=27
http://www.hammockforums.net/gallery...r&imageuser=27

**slowhike** · 12-14-2006, 21:39

i was just noticing those in the photo gallery. looks great.
looks like it would work well.

**Perkolady** · 12-14-2006, 22:11

Headchange4u,

Thanks for posting this project!

I'm learning a lot from them...

Congratulations! Great job !

Perkolady

**Just Jeff** · 12-15-2006, 02:29

Yep - that looks like it'll be a very helpful piece of gear in the cold, as long as condensation isn't a problem. Turned out great.

**headchange4u** · 12-22-2006, 20:56

I wa doing a search on MPP and I came across a comparision between MPP and Tyvek. I went to the Tyvek site and I started doing some reading in the building material suppliers' FAQ section and found some interesting facts out:

What is the difference between DuPont™ Tyvek® and other housewraps?
Many other wraps are perforated, which means in order for them to breathe, the manufacturer has punched holes in them, resulting in a reduction of air and water holdout effectiveness. DuPont™ Tyvek® is a non-perforated, nonwoven product with microscopic pores that are so small air and bulk water have a difficult time passing through but since DuPont™ Tyvek® is breathable, moisture vapor can easily escape from the wall.

Is DuPont™ Tyvek® a vapor barrier?
No, DuPont™ Tyvek® is not a vapor barrier. It is breathable, allowing moisture vapor to pass through it.
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I found this interesting also.

Does DuPont™ Tyvek® have an R-value?
In 2006 DuPont introduced Tyvek® ThermaWrap™, a weather resistive, insulating breathable membrane designed to manage radiant heat flow through the wall. This metalized product helps increase the R-value of insulation.

This stuff MAY be useful in hammock applications. You can see the PDF here.

Tyvek sounds like it would be the perfect thing to make a bottom weathershield. I know from my own experiences that Tyvek is highly water resistant, border-line waterproof, and should act as a windstopper also. The crinkley texture of washed Tyvek may also help to disrupt the air flow oner the bottom of the hammock. Even better, I have a roll of Tyvek setting in my garage. I am thinking about using grommets on the cornors of the Tyvek and 1/2" webbing loops on the side. I may try and pick up some gosgrain if WalMart sells it.

**blackbishop351** · 12-22-2006, 21:09

As a former contractor, my understanding is that Tyvek is a moisture barrier, nothing more. I don't recall hearing about any insulative value at all for a house, except for maybe stopping drafts. Of course, the construction methods used in fairly modern houses don't make for much draftiness anyway.

If you were to use Tyvek as an undercover or travel pod type application, I'd definitely suggest running it through the washing machine several times first, for two reasons. One, it'll make the material softer and more pliable. Stock Tyvek, as I'm sure you know, is pretty stiff. Two, it'll make the Tyvek more moisture permeable. It'll still provide plenty of protection against splash-ups (if used underneath) or the occasional drip, but I think the stock product would be TOO impermeable and you'd get a lot of condensation.

As always, just my .02