The hygric performance of autoclaved aerated concrete is a key determinant for many other material properties as e.g. thermal conduction, carbonation or shrinkage behavior. Laboratory determination of hygric material properties, i.e. moisture storage and moisture transport, is hence a prerequisite and a standard in production and process supervision. In that context, prediction and simulation of the hygric material performance based on numerical calculation models has become a widely used research and design tool. However, for assessment of the material behavior under variable climatic conditions, the hygric material properties have to be determined in a first step. In a second step, these properties have to be transformed into the non-linear coefficients required by these numerical calculation models. This paper is the first out of two focusing on the first step. It introduces different methods for moisture property determination. The methods cover the full range of possible moisture stages. Moisture storage and moisture transport is distinguished. For moisture transport, vapor and liquid phase transport is considered by different direct and indirect methods. The methods are applied for an aerated autoclaved concrete. The obtained data is shown and discussed. In a second step, described in a second paper, this data is used to derive the non-linear material functions required for sophisticated numerical simulation of the hygric material performance.