You got no answer yet. I haven't much knowledge about that, but I want to get some hints. There are some adjusting screws.

...\steamapps\common\SovietRepublic\media_soviet\buildings_types
building.fire - file - I guess removing this file removes the abilitiy to get a fire in that building.
building.ini - parameter - $NO_LIFESPAN - should disable wear and tear

renderconfig.ini - parameter - $LIFE 3000.000000 - should be the health points, so increasing this value should give more time for firefighters to solve fires
-> this is possible for all mod buildings and some standard buildings e.g.
...\steamapps\common\SovietRepublic\media_soviet\cwc\buildings\BusStation2
-> search for renderconfig in ..\steamapps\common\SovietRepublic\media_soviet and you see all possible buildings
-> I didn't find a general renderconfig for all standard buildings.

No, the answer on top is incorrect.
Removing building.fire will result in nothing as the game will renege on it again. Using the same file and making it read only from an already-fireproof building should work.
A building that has no connections and no construction in its configuration is immune to fire. 
Adding the $NO_LIFESPAN token to the configuration will only result in no wear and tear.

Renderconfig.ini has absolutely nothing to do with building behavior and is only responsible for the visualization part. The token $LIFE only affects for how long debris is visible on the ground after demolishing a building without waste management enabled.

Thanks for the revision. I wish there would be an overview of params and their purpose. I couldn't find any form of documentary yet.

Originally posted by Lex713:

A building that has no connections and no construction in its configuration is immune to fire. 

So, if I understand correctly: When I have an embankment and would like to have visitors, I can not remove flammabiltiy at the same time. hm... okay.