Characters need an average of five or more hours of sleep per day (over the last seven days) to function at their best.  Players need to track their daily sleep and apply modifiers to their rolls as appropriate.  Modifiers are not cumulative.

Average Sleep Per Day Effects

Less than 5 -1 DEX

Less than 4 -2 DEX, -1 STR, -1 to hit      

Less than 3         -3 DEX, -2 STR, -1 WIS, -1 to hit, Climbing -2, -25%         Movement

Less than 2         -4 DEX, -3 STR, -2 WIS, -1 CON, -2 to hit, Climbing -4, -33% Movement, 50% Weight Allowance      

Less than 1 -5 DEX, -4 STR, -3 WIS, -2 CON, -3 to hit, Climbing -6, -50% Movement, 0% Weight Allowance

Condition Sleep Amount Modifier

Character not in relaxed position     -1 hour

Lying on bare ground   -1 hour

Temperature below 32 degrees   -1 hour

Character wearing cloth or leather armor   -1 hour

Temperature above 90 degrees   -2 hours

Winds of 20mph or more, with no shelter   -2 hours

Loud noises   -2 hours

Sleeping while hungry   -2 hours

Sleeping while thirsty   -2 hours

Light or moderate precipitation with no shelter   -3 hours

Character wearing mail armor   -3 hours

Character wearing plate armor   -4 hours