Why is polystyrene glued to Puroflex such a good combination for edge boards? In addition to creating a stylish edge beneath a structure, it eliminates the thermal bridge in the floor construction. A good example of this construction can be found in the 20 holiday homes that J.G. Timmer built at EuroParcs Hindeloopen. We used EPS 60. We finished the 2.44 metre planks with a weather-resistant latex coating.