Recent theoretical work has identified that oxygen octahedral rotations (OORs) in layered perovskites such as Ruddlesden–Popper (RP) phases A2[A’n-1BnO3n+1] can generate noncentrosymmetry (piezoelectricity or ferroelectricity) by a “hybrid-improper” mechanism. Our group has reported OOR-induced noncentrosymmetry in n = 1 RP NaRTiO4 (R=rare earth) [Phys. Rev. Lett. 112, 187602 (2014)]. We now extend our understanding of OORs to an n = 2 RP compound, Sr3Zr2O7. Although Sr3Zr2O7 was previously reported to be centrosymmetric (space group Pmmm), we have observed second harmonic generation at 300 K, indicating the noncentrosymmetric nature. We here propose variable-temperature neutron powder diffraction experiments on HRPD to resolve subtle changes in the crystal symmetry resulting from OORs and thus to identify unambiguously the thermally-induced phase transition sequence.