Materials with incommensurate structures often show exotic properties (such as charge density waves). The development of reliable and efficient refinement techniques for such materials is increasingly important to modern crystallography for understanding the correlation between structure and properties. K2SeO4 was the first ferroelectric crystal to show an incommensurate lattice distortion as its primary order parameter in the temperature range 129.5K to 90K. Yet, despite the continued interest in this material, the accepted structural refinement of the crystal is of a very poor quality. Accurate description of atomic positions within the crystal is vital in understanding the coupling between the ferroelectric properties and the different structure modulations. Through this refinement it is hoped to develop the neutron scattering techniques for refinement of incommensurate structures.