Snowmelt slab sensor

Can anyone recommend a snowmelt slab sensor that can report slab temperature and surface moisture directly to a building automation system?  I like the heat timer and Tekmar sensors, but they have to be used with matching controllers.  Tekmar does make a device that connects to the slab sensor and reports to BAS via BACnet.  This is for a hospital ambulance area.  The current design utilizes an ETI slab sensor that senses temp and moisture but only provides a contact closure output (temperature and moisture setpoints are fixed) paired with a thermistor “glued” to the side of the slab sensor.”  Needless to say, affixing any old themistor to the side of the slab sensor, burying it in concrete and and trying to keep the terminations clean and dry sounds like a bad idea.   I have actually seen the Tekmar connected directly to a BAS, but Tekmar’s literature actually contains a disclaimer stating that using the sensor in this manner voids the warranty.  One nice thing about the Tekmar and heat timer sensors is that they come with nice length of  direct burial cable factory installed, so no terminations required under the slab.