i mean exterior shell of the house uncombustible. then its impossible to set on fire by embers. and radiation heat would be needed of absurd intensity or set furniture inside on fire. and again there were no such intensity, look at these tree's standing among completely burned out residential area, even with all these houses burning heat wasn't so intense. without houses burning all you have is wind carrying embers from burning forests and for cement/metal exterior house it's nothing burger.
Anarcho-Capitalist