N.C. Gen. Stat. § 47C-2-111

Subject to the provisions of the declaration and other provisions of law, a unit owner:

(1) May make any improvements or alterations to his unit that do not impair the structural integrity or mechanical systems or lessen the support of any portion of the condominium;

(2) May not change the appearance of the common elements or the exterior appearance of a unit or any other portion of the condominium without permission of the association; and

(3) May, after acquiring an adjoining unit, remove or alter any intervening partition or create apertures therein, even if the partition is a common element, if those acts do not impair the structural integrity or mechanical systems or lessen the support of any portion of the condominium. Removal of partitions or creation of apertures under this paragraph is not an alteration of boundaries.