Within the area of a consecrate effect, a cleric's ability to turn undead is boosted. Any undead creature in the vicinity is weakened by a minor disruption effect. Undead also cannot be created within or summoned into a consecrated area.
Consecrate does not work as intended if there is a similar fixture dedicated to a different deity. Instead, it curses the area, cutting it off from the associated deity or power. This secondary function doesn't produce the bonuses against and penalties to undead.
Consecrate requires the expenditure of a vial of holy water and five pounds of silver dust, all of which must be sprinkled around the area to be consecrated.