B.W.
I actually got a good deal on the 'Space bags' and had put all my maternity clothes in those. They really do get down to a small flat size. If I were you, I would somethign like that, then put them in the garbage back (extra protection) then sling them into the attic. I actually put comforters, blankets and pillows in those too and they pop right back to shape when I reopen the bag. Great space savers.