Editing Roof and tunnel hacking (section)

===Risks to building infrastructure===

Utility tunnels carry everything from drinking water to power to fiber-optic network cabling. Some roofs have high power [[radio broadcast]] or radio reception equipment and weather-surveillance equipment, damage to which can be costly.  Roofs and tunnels also may contain switches, valves, and controls for utility systems that were not designed to be accessible to the general public.

Due to security concerns there has been a trend towards installing [[burglar alarm|intrusion alarms]] to protect particularly hazardous or high-value equipment.