Tex. Property Code § 82.062

Subject to the declaration, the boundaries between adjoining units may be relocated by an amendment to the declaration on written application to the association by the owners of those units. If the owners of the adjoining units have specified a reallocation between their units of their allocated interests, the application must state the proposed reallocations. Unless the board determines not later than the 30th day after the date the application is received that the reallocation is unreasonable, the association shall prepare an amendment that identifies the units involved, states the reallocation, is executed by the applying unit owners, and contains words of conveyance between them. At the expense of the applying unit owners, the association shall prepare and record the amendment and plats or plans necessary to show the altered boundaries between adjoining units, and the units' dimensions and identifying numbers.