A system, apparatus and method for monitoring structures is provided. The system includes a measurement acquisition unit having a first connection point for receiving a sensor unit and a second connection point that is electrically isolated from the first connection point when invoking the sensor unit. A measurement sensor for detecting moisture includes a pair of spaced apart conductors; and an impedance circuit in parallel with the conductors and having a finite impedance such that an impedance of the measurement sensor greater than the finite impedance indicates an impaired connection. A termination module includes a base attachable to a measurement sensor, and the impedance circuit. A moisture content measurement sensor includes: a pair of conductors in electrically insulating material; and electrically conductive probe supports attached to the conductors for receiving probes and forming electrical connections between conductors and probes. Eyelet rivets may be used as probe supports.