VegProtect

Vegetation as protection of historic buildings against rock moisture and weathering (VegProtect)

Changing global climate makes it increasingly necessary to protect cultural assets from the hydroclimatic effects of climate change and to prevent weathering and moisture damage. Wall greening makes an important contribution to the climate resilience of cities and buildings and has a positive effect on biodiversity. However, there are often reservations about tolerating or deliberately planting vegetation on historic buildings, as there are concerns about harmful effects from lichen, mosses and plant roots. VegProtect is intended to provide reliable data on the influence of vegetation on the moisture balance and make this knowledge known to decision-makers in monument conservation in order to increase acceptance for wall vegetation.

The investigations focus on the impact of different types of vegetation (lichens, mosses, deciduous and evergreen climbers, herbaceous plants) on microclimate and rock moisture. The key question is which type of vegetation has a particularly strong protective effect and no negative effects with regard to weathering. The results will be incorporated into a guideline that shows the hydrological effect and weathering potential of wall vegetation and thus contributes to a better assessment of the opportunities and risks of greening heritage sites.

For this purpose, sensor systems will be used to measure rock temperature and electrical conductivity, supplemented by hand-held microwave sensors to record the spatial moisture distribution, and 2D-geoelectrics to determine the moisture at greater rock depths. In addition, microclimatic investigations (temperature, humidity, driving rain), hydrological parameters (porosity, water absorption) as well as investigations of the root effect and the degree of weathering will be carried out in the laboratory and on site. The measurements will be carried out at three castles and a building in Franconia, where the effect of vegetation of various sizes can be investigated. Additional measurements will be carried out at a university building in Antwerp and a ruined monastery in Oxford (UK), as well as on open-air test walls at the universities of Bayreuth and Oxford.

Funded by: Deutsche Bundesstiftung Umwelt (DBU)

Planned project duration: Jan. 2025 - Dec. 2027 (or after staffing)