Excavator: Ground. The females of this species typically nest in extensive aggregations in the vertical faces of sand pits, roadside sandstone cuttings, mud (and cob) walls and in sandstone cliffs. An aggregation of some 300 nests has been found in the soil between the roots of an upturned tree (Boreham, 1955b). Nests excavated in level soil seem to be unusual. The bee has gained some notoriety from its habit of burrowing into soft, sandy or limy, mortar joints of masonry. In extreme examples, when an aggregation may contain a considerable female population, the joints become riddled with hundreds of burrow entrances.
Nests, and particularly nest sites of this bee have been exhaustively described by Mader (1999); his account contains numerous photographs of nest burrow aggregations in different geological exposures in Germany.