Angle board and insulation board on stairs. It is a new product for building market. The system is designed to be used as an insulation material for outdoor underfloor heating stairs to protect them against snow and ice. Insulation board (Thermopanel Sp) and an Angle board (Thermopanel Sk) with an XPS core, is reinforced with a glass fibre mesh and covered with a cement polymer with furrows for heating cable installation. Thermopanel S is an exceptionally durable and easy to cut insulation board. This system can be installed outdoors in damp areas has insulation properties and the ability to provide sound insulation. This system allows to increase the heating efficiency of snow and ice protection systems (the warm-up time is shorter) and decrease the running cost. It can be fixed to tiles or any other kind of floor covering.