Thermodynamics and radiant heat are a bitch. There are three ways heat moves: conduction, convection, and radiation. The first is not an issue, the second is what most people think spreads that fire, but it is the third, that really drives fires. When a cloud of 500 degree smoke completely covers an area, equilibrium principles make that under the cloud become 500 degrees. To protect houses, you have to remove the fuel a quarter mile upwind, where the smoke is getting its heat.
In very high winds and depending on fuels, etc., more than 1/4 mile upwind... But, yes, good points.
Still, homes CAN be built to resist 500 deg. F or more, at least for a while. It tends to be pricey, though.
This is the same as the relatively recent discovery of something called Pyroclastic Flow, which is a rushing mass of superheated gas and particles from an erupting volcano. In 1902, a massive pyroclastic flow from the erupting Mt. Pelee on the Island of Martinique killed about 30,000 people in the major city San Pierre. For a while people who had moved away were given a daily subsidy for food and shelter. When after a few months they were tired of giving this “wellfare” about 2,000 people moved back to a town that the scientists said was still very much at risk from the volcano. There was another pyroclastic flow, and almost all 2,000 were roasted to death.