Renewal Communities Expansion and Technical Improvements Act of 2004 - Amends the Internal Revenue Code to: (1) qualify employees who reside in any renewal community for purposes of the empowerment zone employment credit; (2) extend the exemption from the limitation on the use of community development block grants for provision of public services to renewal communities; and (3) authorize the Secretary of Housing and Urban Development to expand the boundaries of a renewal community to include other adjacent and noncontiguous areas, including areas of high economic distress.