Thermal Overcover...Possible?

**dosei** · 11-06-2014, 12:45

Not exactly sure where would be the best place to post this, but I figured since Papa Smurf / Dream Hammocks seem to be up on the latest stuff I'd post it here...

Are there any thermally reflective fabrics that would lend themselves well to being used as an Overcover (or at least for "lining" the interior of an Overcover)?

Just thinking aloud, it seems to me that having an Overcover (vented, of course) that is thermally reflective on the inside could give the setup a significant improvement in cold-weather comfort. An added bonus would be that small light sources like the nite ize spotlit light would be enough to illuminate the interior surprisingly well. Is this something people have already been looking into or playing with? I know many people use reflectix underneth themselves in hammocks, but often it does not allow enough airflow between the body and the reflectix resulting in that "warm but clammy" condition that is not desirable.

**PapaSmurf** · 11-06-2014, 21:46

I don't see why something like this wouldn't work as long as we maintain enough ventilation. DIY Gear Supply used to have soe of this fabric, but I don't recall if it was breathable at all. I suppose the key is finding the right material.

**autolox** · 11-06-2014, 22:34

Might be kinda nifty to figure a way to attach the most common size of a space blanket to the inside of the over cover?

..Hmmm....what about tarp pull outs on the inside of the cover and attaching to grommets in reflectix or a space blanket?

**Zilla** · 11-06-2014, 22:47

Yup, mylar space blanket with velcro attachments, should be doable for under ten bucks.or just make a tq liner out of a space blanket.

**PapaSmurf** · 11-06-2014, 22:50

Maybe? I gotta do some searching on these fabrics when i get a chance.

One idea that's been on the back burner for awhile is building an overcover with a layer of Climashield between 2 layers of lightweight ripstop. The overcover would not be zipped over the ridgeline, but under it so that it would lay coloser down against you. Would need to figure out a head hole or way to seal off the end. Maybe a large noseeum window? This idea is not my own, but came from a similar top cover developed by Slowhike. I'd just put ThunderBird zippers along the edges.

**Zilla** · 11-06-2014, 23:04

Originally Posted by PapaSmurf

Maybe? I gotta do some searching on these fabrics when i get a chance.

One idea that's been on the back burner for awhile is building an overcover with a layer of Climashield between 2 layers of lightweight ripstop. The overcover would not be zipped over the ridgeline, but under it so that it would lay coloser down against you. Would need to figure out a head hole or way to seal off the end. Maybe a large noseeum window? This idea is not my own, but came from a similar top cover developed by Slowhike. I'd just put ThunderBird zippers along the edges.

Ok, well this is a much better idea, them darn fancy smurfs.

**dosei** · 11-07-2014, 11:50

Finding the right material is indeed the trick. The "ideal" material would be thin, strong, light, silent, and (ideally) breathable. Mylar fails miserably in the silent & breathable categories. Sandwiching the material in-between two layer of ultralight ripstop is a superb way to protect it, but doing so removes the interior lighting benefits. Since the 11' Dream Hammocks have so much headroom that even tall people can actually sit up in them, having an over-the-ridgeline overcover that holds in the heat would give the user a more cozy place to sit in the morning while getting bundled up to step out of the hammock and face the cold...your own personal suspended suite.

**thesilence** · 11-07-2014, 12:05

If you can find the Omni-Heat fabric that Columbia uses in its jackets that could work.
http://www.textileworld.com/Issues/2...cta_For_Warmth

**dosei** · 11-07-2014, 12:36

Originally Posted by thesilence

If you can find the Omni-Heat fabric that Columbia uses in its jackets that could work.
http://www.textileworld.com/Issues/2...cta_For_Warmth

The problem, in my opinion, with so many of the products that use thermally reflective material is that they put it in the wrong place. For optimum comfort you want your body heat to pass through the insulation (trapped air) and then hit the thermally reflective material and thus be reflected back through the insulation and finally to you body. This way the thermally reflective material provide the maximum benefit of warming the insulation. Putting the material between your body and the insulation only means less of your body heat will be available to warm the insulation, and you will be more likely to experience that "warm/cold clammy" sensation that most people dislike. The reason they put it where they do (again, in my opinion), is to make it eye candy/bling for the consumer..."Ohhh look, SHINY!!!". If a person is in hypothermia then YES put the space blanket right up against their skin, they don't have the thermal reserves to heat up any high-loft insulation. But for non-emergency applications, the better set-up is: body - soft/smooth breathable fabric - insulation - thermally reflective material (breathable) - wind/water resistant (but breathable) outer fabric.