Antennas mounted on existing structures
Cellular panel antennas may be mounted on existing structures. These panels may or may not be camouflaged, but in either case mounting on an existing structure eliminates the need for a pole and is usually considered an attractive option when a suitable structure exists. If the building is selected as a site and has a flat, accessible roof, it may also be able to house the equipment shed, eliminating the need for a chain link fence and equipment shed normally seen at the base of a monopole.
In Manhattan, existing buildings are the most common locations for cellular antenna. Unlike in most of New York State, antennas are allowed on most buildings as-of-right and are not subject to any discretionary review.
Because they can usually be installed as-of-right, camouflaging is not typically installed, even when the antenna are installed on older buildings, as can be seen on this 100 year old building on Manhattan’s Upper East Side. Nevertheless, it is possible to camouflage the antenna on buildings with screens similar to those put on the silo shown earlier.
The screen on the top of this Upper East Side building hides two arrays of antennas on either side of the building, though it could be easily argued that the screen is not an effective mitigation measure.
In dense urban areas like Manhattan, panels are found at lower heights than what is typical outside the City. Considering network performance, panels mounted on top of a five-story building (~50 feet) in New York City may be preferable to a 120 foot monopole. But such a configuration outside the City is typically unacceptable where taller structures are needed to get over the existing tree canopy and to obtain the range desired. Often, the few structures that meet these criteria are institutional structures like electrical towers, water towers or exhaust stacks.
Water towers are popular locations due to their height and mass. In most cases, other than matching the color of the tower, panels located on water towers are not camouflaged, but are still hidden by the overall mass of the structure on which they are located. From a visual standpoint, antennas mounted on the side of the water tower are preferable to those mounted on the top.
Some communities have public works or industrial facilities that at one time were equipped with incinerators or large boilers that required tall smoke stacks. Even though these facilities may have been decommissioned long ago and the building is used for other purposes, the surviving stack may make them suitable as wireless communications sites.
The best of these mount the panels directly to the chimney and match the color of the panels to the color of the chimney.
Many of these large structures are publically owned, and when public property is used for the purpose of citing cellular antennas the benefit to the public is three-fold. First, the visual impact of locating the panels on the existing structure is typically smaller than it would be for most other techniques. Second, the public gets the benefit of a revenue stream from the lease with the wireless company, which installs and maintains their equipment. Finally, the wireless network is improved, providing more capacity and signal strength to users in the community.