40 Pa. Code § 7.23
The additional premises for which it is desired to extend a license shall be completely equipped for the carrying on of the type of business permitted under the license, but no sales of liquor or malt or brewed beverages, storage or similar activity may take place in the additional premises until approval has been given by the Board. Where the extension of premises involves physical alterations or new construction, the Board may grant prior approval for the extension, as similarly provided in section 403(a) of the Liquor Code (47 P. S. § 4-403(a)). The application for extension of license shall be accompanied by a written request for consideration, together with floor plans as set forth in § 7.8 (relating to floor plans) clearly showing the premises as it will be after the alterations or construction are completed. If the additional premises the applicant intends to license has not been constructed at the time the application is filed with the Board, a site plan shall be submitted as set forth in § 7.9 (relating to site plans). Approval may be in the form of a new license, giving the additional address or a letter authorizing the use of additional premises. In the case of distributors and importing distributors of malt or brewed beverages, no sales of malt or brewed beverages may be made in a warehouse except that in which the office or principal place of business of the licensee is maintained.
40 Pa. Code § 7.23