PURPOSE: To improve the handling property and the strength by arranging a heat insulating slender piece formed of a synthetic resin between metallic hollow sections to form a spacer, and arranging a spacer between panes of glass.

CONSTITUTION: A pane 1 of glass and a pane 2 of glass are arranged parallel to each other with an interval therebetween, and a conductive passage 5 of a resistor heating element is provided on the surface 4 of a hollow space of the pane 2 of glass. A slender piece 16 formed of unfoamed and cured polyurethane casting compound is arranged between aluminum hollow sections 7, 8 whose inside is filled with a desiccant 11 to form a spacer 6. The spacer 6 is arranged in an intermediate space 3 between the panes 1, 2 of glass, and a space 13 below the spacer 6 is filled with a thioalcohol 14.