Polyfoam XPS Ltd is a leading manufacturer of closed-cell, extruded polystyrene insulation. Their products are manufactured in the UK using methods with low global warming potential (GWP) and zero ozone depletion potential (ODP). We stock the Polyfoam Roofboard Extra, a rigid extruded polystyrene (XPS) board. This product is tough, durable and not easily damaged and it boasts an excellent declared thermal conductivity of 0.033W/mK and high compressive strength.