The spin Seebeck effect is a newly discovered phenomenon that if harnessed, could result in a significant improvement of the efficiency of thermoelectric energy generators. Spin polarised neutron reflectivity will provide us with complementary measurements that enable determination of the spin polarisation of the film as well as surface sensitive magnetic ordering and disorder at the interface. This is especially important as the influence of the interface (i.e. the magnetic proximity effect) is still not well understood. We propose using PNR in conjunction with an adapted sample environment in order to investigate the magnetic structure (as a function of depth), whilst measuring the generated spin Seebeck voltage for samples with varying degrees of spin polarisation.