electro - portable apparatus for producing steam applied to a surface , usable more particularly but not exclusively for ungluing wall coatings , having a housing containing a porous body impregnated with a liquid to be vaporized , the liquid being heated up to its temperature of vaporization , the housing 2 being subdivided by a partition wall 8 , 27 , into two compartments , namely a rear closed compartment 9 , 28 containing a steam generator 12 , 13 , which is formed of the porous body 12 impregnated with liquid and a heater 13 for heating this liquid , and a front compartment 11 , 29 forming a vapor cavity or &# 34 ; steam plate &# 34 ;, open to the outside , defined by a peripheral edge able to be applied on the surface 1 adapted to receive the vapor , and openings 31 being provided through the partition wall 27 to allow the passage of the steam , produced in the rear compartment 9 , 28 , towards and into the front compartment 11 , 29 constituting the vapor cavity or &# 34 ; steam plate &# 34 ;.