I need to make a cotton storage bag for my quilt. I know, it’s better to keep it uncompressed, but can’t do that. The quilt has 12 oz. of down. Is there a ‘rule of thumb’ for storage compression?

If you’ve got 850 fill power down, then you should leave 850 cubic inches for each ounce of down, which works out to about 167 liters *uncompressed* in your case. So, that’s the most you’d need. You can figure out how much smaller you want to make it.

I guess the rule of thumb for storage compression is “don’t” or, barring that, “as little as possible”.

—Peter

Thanks, I have to compress it for hiking, and it takes it’s toll, but, it comes back, especially if it’s hung in the sun for a while. Storage will be uncompressed.

Sorry, I thought you were asking about storage compression from your original post. As far as compression during a trip, I just stuff my sleeping bags into the smallest bags they’ll fit in. My Marmot Helium EQ—19.5 oz fill weight, 850+ fill power down—fits in an XS stuff sack. Yes, it’s very warm!