Tex. Prop. Code § 81.109

An apartment in a condominium regime and the undivided interest of an apartment owner in the common elements of the regime that are attributable to the apartment may not be conveyed separately. If a conveyance of an apartment does not refer to the common elements, the undivided interest of the apartment owner in the general and the limited common elements of the regime attributable to the apartment is conveyed with the apartment.