that is welded to base plate 122 which has a cutout 123 to allow leads 36 and 37 to enter fitting 120 base plate 122 can be screwed into the bottom of the surface structure using a self tapping screw that passes through opening 124 of plate 122 and is accepted in a pre drilled hole in the surface structure the epoxy layup helps to hold fitting 52 in place so that it forms a secure coupling location for the power leads conductors 31 and 33 are preferably flat copper conductors that are insulated for example by wrapping them with double sided tape or in another fashion a temperature sensor for example a thermistor assembly 110 is located at base fitting 52 and in gap 14 a to allow sensing of temperature for purposes of power control the temperature sensor could also be accomplished with a thermocouple or an rtd for example as shown in fig5 thermistor assembly 110 includes thermistor 111 wires 112 and solder sleeves 113 an exemplary installation of the surface structure assembly 8 in a concrete substrate 102 is shown in fig6 assembly 8 includes radiant heating system 10 coupled to the underside of surface structure 80 conduit.