§ 415-50 ROCKLAND CODE § 415-52 § 415-50. Land use density. A. No areas devoted to single-family detached residential structures shall have a density in excess of four units per acre exclusive of all street rights-of-way. B. No area or areas devoted to multi-family residences shall have a density in excess of 15 units per acre exclusive of all street rights-of-way. C. Each of the above residential density limitations shall be mutually exclusive of each other and shall not be cumulative. D. The prepared "grid" subdivision will only encompass that portion of said land which is not defined as wetlands under the Massachusetts Wetlands Protection Act.18 The total number of dwelling units within a Planned Unit Development shall not exceed the total number of dwelling units which would be permitted on the non-wetland portion of the parcel developed in a traditional (or grid) manner. E. No area devoted to Residential Senior Housing single family detached residential structures shall have a density of more than 10 units per acre exclusive of all street rights-of-way, with the total number of dwelling units determined in accordance with Subsection D. [Added 5-12-2003 ATM, Art. 8] § 415-51. Common recreation areas. In connection with residential structures there shall be provided at least one square foot of common recreation area for each two square feet of residential floor area. The required common recreation area shall be provided in a lot, or lots, of at least 21,780 square feet that is free of structures associated with the residences in the Planned Unit Development. Common recreation areas shall be delineated on plans submitted to the Planning Board for review with the size of the area noted. Provisions for delineating this area in the finished development, method of delineation subject to Planning Board approval, shall be made by the developer. Common recreation areas shall be developed with either active or passive recreational facilities or both. No facility in which the residents of the planned unit development are excluded by outside or private membership shall qualify for the purposes of the requirements herein. § 415-52. Open space. A. Each planned unit development shall develop and maintain the following required open space: One square foot of open space for each one square foot of total gross floor area of the planned unit development, but in no event shall less than 35% of the gross land area of the planned unit development be open space. B. Computation. 18.Editor's Note: See MGL c. 131, §§ 40 and 40A. 415:146