Roof with thermal insulation of the slope made of extruded polystyrene boards on full boarding above the rafters, makes it possible to display the roof truss as an element of interior finishing.
On the formwork there is a vapor barrier made of polymer-bituminous roofing felt. Installation of heat-insulating boards made of extruded polystyrene begins with nailing to the edge of the eaves a wooden batten with a height equal to the thickness of the boards. The consecutive rows of boards are placed tightly pressed on the locks with a staggered shift. The joints of the panels should be filled with polyurethane foam. Thermal insulation boards are fixed to the rafters through counter battens and formwork with special nails or screws. Counterbattens should be pre-drilled, that the fasteners do not crack or split. Counter-battens must be used to provide a suitable base for the battens or formwork of the roof covering and for sufficient ventilation, the minimum thickness 4 cm.