Jörg Jude Gebäudetechnik
Thermal and convective drying of wet basements
Masonry often has an increased moisture content caused by ascending water or constructional damages. For the preparation of redevelopment measures or for a near-term usage the masonry is supposed to be dried quickly. With common used procedures like constructional dryers there is the problem of the disposal of evaporated water from deeper layers of earth especially with thick masonry in wet basements. Special packers that are operated with a compressed air supply and an electrical heating unit with low voltage which are brought for an injection into the masonry anyway are tightly wounded into the respective masonry. The heating packers are inserted into every second drill hole and the pressure initially is raised to the extent that an airflow starts into both neighbouring drill holes through the porous masonry. Is the masonry heavily saturated with water often there can be then observed that water in liquid phase passes out at the walls of the free drilling holes. After activating the radiator the air which is streaming through the masonry is heated, the water evaporates and is led away to the outside by the airflow over the free drilling holes. In this way the masonry can be dried in a relatively short period of time. Drying the masonry by capillary transportation of the water to near surface areas with following vaporization to the outer air harmful salts to the construction are accumulated on the surface which can lead to plaster or stone damages. Basically in water dissolved salts crystalize only there where the water vaporizes. Is the water within the masonry vaporized like described in the thermal convective drying process then also the salts stay there and cannot do any damages on the surface.
