Doublespace

The doublespace spell allows a volume of space to "be" two times larger than it actually "is." In addition, objects in the doubled space have an effective weight of half their "real" weight. For example, if a 7th-level mage casts doublespace on a cargo hold with a volume of 875 cubic feet, the cargo hold would then have an effective volume of 1,750 cubic feet. The spell is great for packing extra cargo onto a ship and can vastly increase the profit margins of merchant vessels. The spell can only be used on inanimate objects.

If the spell expires while material remains within the folded space, or if a successful dispel magic is cast upon the area, disaster can occur as the material suddenly occupies its original volume. The doublespace immediately ceases to function if any dimension-altering spells or magical items (such as rope-trick, dimension-door, teleport, portable hole, or a bug of holding) are used within the area of effect.

The material component (consumed) is a 1" wide strip of paper (worth not less than 1 gp) twisted and joined so as to only have one side.