One of the most rapidly expanding forms of zoning is the adoption of esthetic zoning regulation by some communities. These ordinances describe what is and what is not permissible for a land owner in terms of landscaping, color schemes, mailboxes, fences, solar panels, decks, satellite dishes, types of materials, shapes of roof, and so forth. Esthetic zoning ordinance may require that building plans be submitted and approved by an architectural review committee before the "hammering" begins.