Adding a zipper to a sleeping bag

[3bdulHazred]

I got a 20F bag years ago for a trip only to find out it didn't have a zipper, and is just a tube. Very light, very warm, no ventilation. The past weekend has taught me that I'm in need of something to keep me warmer than my beloved 40F bag. Instead of buying new, I'm considering adding a zipper to my 20F bag, or maybe even turning into a quilt. (Insulation should be synthetic.)

Has anyone done anything similar? What should I be careful of when starting this project.

[bluesam3]

Turning it into a quilt is definitely the easiest option: just cut it open to the shape you want the gap to be, and sew the sides up.

However, if you don't already have an underquilt, I'd get one of those first: no amount of fancy top quilt/sleeping bag will keep you warm without one (or something roughly equivalent) in anything but the warmest weather.

[3bdulHazred]

Turning it into a quilt is definitely the easiest option: just cut it open to the shape you want the gap to be, and sew the sides up.

However, if you don't already have an underquilt, I'd get one of those first: no amount of fancy top quilt/sleeping bag will keep you warm without one (or something roughly equivalent) in anything but the warmest weather.

Good advice. I have a couple of UQs already. I went to the ground this past weekend to appease my SO and realized that if I'm mountain camping, my 40F bag isn't going to cut it even in July.