The relevance of the microwave electromagnetic field risk management may include 1) protecting sensitive electronic equipment from the electromagnetic interference, 2) counter-espionage including neutralizing electronic surveillance and 3) the protection of the personnel wherever strong microwaves are encountered. Also, it has been suggested that certain people in risk groups, may be more vulnerable to the microwaves than others. This study investigates 2.4GHz microwave electromagnetic field reflective properties in contact with various construction materials used both in indoor and outdoor environment. The reflection amplitude of the materials was measured by a setup involving a microwave source and a radiofrequency electromagnetic field peak detector. All the tested materials exhibited some reflective properties. The strongest reflections were recorded from gypsum board on an iron wire mesh; the least reflections were recorded from the gypsum board on a silicate brick. The results suggest, that in assessing the microwave reflective properties of the building, the complete structure of the element must be taken into account – while the first layer material such as gypsum board may allow the transmission of the microwaves, the following layers may present a reflection. The data obtained by these measurements helps designing buildings where the microwave mitigation is a necessity.