Half quilts

I’ve had similar thoughts about contortionists.

Could a contortionist get by with a half length tent as well as a half length sleeping bag?

I couldn’t do it personally.  If I got a leg cramp I’d probably kick a hole through both.

I don’t think people often stay in the same fetal position all night.  Any stretching and your insulation would disappear.

If you want to know the impact, EE sells junior quilts:

https://support.enlightenedequipment.com/hc/en-us/articles/115002179667-Revelation-Junior

a 66″x54″ 30 degF Rev jr with 900 Fill weighs 14.2 oz

a regular weighs 16.5 oz (78″x54″ 30 degF Rev with 900 Fill)

https://support.enlightenedequipment.com/hc/en-us/articles/115002191628-Revelation

of course you may need more width since your bundled up in a ball, x-short/x-wide weighs (66″x64″) 16.4 oz

Not quite the same, but some mountaineers use a half bag.  They come up to mid-torso and are intended to be used w/ a thick puffy jacket.  Filled with down and a 20F – 30F rating, the weigh around 8oz.

You could see how you like this concept by safety pinning 2 old sheets together and spending a night in it in bed.  Maybe you could just fold one sheet up to make a pocket, crawl in and lay on top of the folded edges to keep it together.

Once you get a sense for size, you can estimate weight.  In theory, you should be able to go a bit colder than the standard rating for a given amount of insulation because the fetal position is better for conserving warmth and the bag will have a better surface area to volume ratio.

I don’t think you’ll get as low as half the weight, but 25% – 30% savings seems reasonable.

https://www.mid-atlanticmountainworks.com/store/p120/XCUSE_Half_Quilt.html

Thank you all, i’ll keep the advises in mind when committing to my first quilt

I’m 5′ 6″ tall and sleep mostly on my side with my knees up a bit and started off with a short quilt that just barely came up to my chin when laying flat on my back. After spending a couple of years with that setup I now have a quilt that barely reaches the top of my head when flat on my back and I’m much, much happier with it.

I used to use a 48X25 pad but now use a 66X20. I’m super happy with that as well.

Even though I’m on my side curled up most of the time it turns out that I am significantly more comfortable with room to stretch out. YMMV.