Understanding the forces acting on macromolecular structures at surfaces is vital to a number of different branches of science and engineering, ranging from bio-fouling to surface lubrication. We have recently published a demonstration of a potential next step for the analysis of surface forces and their structural implications, using the semi-permeable nature of charged lipid membranes to directly compress surface bound polymer layers as a function of the applied electrical potential. This is particularly exciting as this is the only approach where confinement can occur in fully hydrated conditions. Therefore, in the scope of this study, we will used polarised neutron reflection on POLREF combined with buried permalloy layers to provide a magnetic reference layer to follow the compression of PEG layers as a function of applied voltage and the grafting density of the polymer layer.