The lower the 'U' Value of a material the better the materials
insulation properties are. The properties of Spray foam are superior
to other Insulations. In other words it takes less thickness to
achieve the same insulation values as a other materials.
A 75mm layer of sprayfoam applied to the underside
of a slate or tiled roof, is sufficient to achieve a U-value of
Because its spray applied and cures in seconds, it
means that any thickness can be applied depending on requirements.