The presence of frustrated spin networks in most spiral multiferroics produce low magnetic transition temperatures (T_S).  In the layered YBaCuFeO₅ perovskite the extraordinary tunability of T_S is controlled by Cu/Fe disorder. But also by lattice effects induced by chemical pressure that, keeping disorder invariant, effectively tune magnetic frustration through changes in the size and separation of the bipyramids. Here we investigate the impact of external pressure on the structure of YBaCuFeO₅ and the stability of its spiral magnetic phase. In spite of a substantial compression of the elongated divalent pyramid and of the thickness of the bipyramids below 6 GPa, the thermal stability of the spiral magnetic order is unambiguously reduced under application of pressure (initially at dT_S/dP =12K/GPa). The decrease in the collinear-to-spiral transition temperature by applying pressure was independently confirmed by susceptibility and neutron diffraction experiments. Above 4 GPa, Raman spectroscopy reveals changes in the coupling of some modes to the continuum of magnetic excitations, becoming totally decoupled above 6.5 GPa.