International audience This paper focuses on how the design, aesthethics and atmosphere of a new hospital birth environment affects the experiences of new fathers. Based on a phenomenological study it shows how atmospheres are experienced in a new birthing room intended to stimulate the senses in a comforting and equanimity-evoking way, and especially how the fathers attuned themselves to the situation of being present at the birth of their new-born infant. Studying fathers’ transition to parenthood through the lens of atmosphere and interrogating the meaning of atmosphere in hospital rooms offers a more nuanced approach to our understanding of the relationship between people, space, time and event in future design of new hospital rooms.