A painless option to make enchanted armour lighter than normal
Magic armour is, in many ways, its own reward. But here’s an additional bonus that boosts the value of enchanted protection even more.
At the DM’s option, magic armour, in addition to its protective bonuses, may also grant a weight reduction. For every “plus” of the armour, lower the armour’s ENC value by 10%. For example, a shield +1 would be 10% lighter than a normal shield (100cn) for a total of 90cn. A suit of chain mail +3 would be 30% lighter than a normal suit of chain mail (400cn) for a total of 280cn.
Note that the standard restriction on magical “plusses” is +5, so no enchanted armour can weigh less than 50% of its normal counterpart. To be consistent, it is recommended that cursed armour imposes an encumbrance increase of +10% for every -1 penalty (i.e., a shield -1 would weigh 110cn).