Cams Hall was designed a conservation area in 1982. The estate occupies a peninsula of land formed by the curve of Fareham Lake as it flows from the mouth of Wallington river into Portsmouth Harbour. It includes the whole estate, the north and south parks and the significant belts of trees known as Cams Plantation. The boundary follows the shoreline around the peninsula as far as Cams Bay where it turns north to follow the Cams Plantation tree belt. It rejoins Portchester Road (A27) to the west of Cams Hill School and returns along the front of the estate to the head of Fareham Lake. At the time of designation, all buildings on the estate were neglected and collapsing and buildings of the Home Farm and the Walled Garden were not statutorily listed, with the exception of the Orangery and Stables. The quality of the landscape was damaged and deteriorating, many of the distinctive trees being lost to disease and neglect. The designation secured the preservation and restoration of the estate. All historic buildings were subsequently added to the statutory list in 1989.