Like almost all building materials, high moisture contents for longer periods of time can lead to severe moisture damages in wood. However, since wood is a biological material, it is also prone to biodegradation by wood destroying fungi, which considerably reduces the strength of a timber construction. Moisture damages very often occur in covered areas such as wet rooms (e.g. cross laminated timber (CLT) ceilings and covered dry walls), where moisture accumulation can occur without being noticed for a long time. The current paper describes the development and application of novel printed moisture sensors, that can be integrated directly into wooden construction elements, such as CLT or Glulam. This allows continuous in-situ monitoring of wood moisture content. A special wood primer was developed for the inkjet-printing process that is required to obtain high printing resolution and efficiency. The optimal sensor geometry on wood for highest measurement sensitivity was found by systematic variation of geometric details of the sensors and measuring conductance and impedance during a climate trial. The relative humidity was gradually increased while keeping the temperature constant within the chamber. After each step of moisture increase, impedance, phase angle and deduced variables at different voltages, currents and frequencies were measured. Furthermore, a proprietary measurement system was used. With the novel printed moisture sensors, it was possible to reliably monitor accumulation of moisture within CLT elements.