A furling group (1) usable for furling a flexible membrane body (50), presenting a given perimeter (51) comprising a first edge (52) delimited by a pair of coupling members (54) and able to be furled about an elongated member (55) coupled to the first edge (52) itself; the furling group (1) comprising a third base (10) designed for being coupled stably to a given surface (3) and a furling device (40) carried by the third base (10) and presenting at least a first hooking member (31) usable for coupling to the elongated member (55); the furling group (1) also comprising a turnbuckle device (30) designed for varying substantially at will an axial position of the first hooking member (31) along a given longitudinal direction (D) in order to adjust a longitudinal tension of the first edge (52).
