W. Va. Code § 48-9-102a: Presumption in favor of equal (50-50) custodial allocation.

There shall be a presumption, rebuttable by a preponderance of the evidence, that equal (50-50) custodial allocation is in the best interest of the child. If the presumption is rebutted, the court shall, absent an agreement between the parents as to all matters related to custodial allocation, construct a parenting time schedule which maximizes the time each parent has with the child and is consistent with ensuring the child’s welfare.