Stylite Clayfil Product Overview Stylite Clayfill is a low density Expanded Polystyrene (EPS) compressible fill that helps reduce any forces exerted onto deep fill foundations, concrete ground beams and piled foundations. These pressures can be caused by many things, the expansion of clay soils, excess water or overgrowth of tree roots. Whatever the reason for the development of these forces Stylite Clayfill can help absorb the pressure exerted onto the foundations. Alternative brand to Jablite Claymaster