Mason: Existing cavities in stones and in depressions, cracks or surface irregularities of stones, rocks or walls with 2-8 cells. Nesting material: The cells are made of sand (Westrich) or from pebbles cemented together with mud (Müller). The nest is covered by an outer coat of mud. (Banaszak and Romasenko, 2001; Benoist, 1931; Bonelli, 1969; Ferton, 1901a; Friese, 1923; Gogala, 1999; Westrich, 1989)
Stanisavljević (2000), probably copying Banaszak & Romasenko (1998), state that the species nests on rock and stone surfaces, making the brood cells from small pebbles glued with mortar. The cell walls are plastered with mortar from the inside, and then the entire nest is covered with a common mortar layer. There are between 2-8 cells in a completed nest