Woodland Mansion spawns next to lava and burns down

The Woodland Mansion spawns in contact with lava and burns down. Not a bug as such but disappointing on a SP map.
Perhaps lava should be removed from the area around a mansion.
Tested with 16w41a on my SP world and 16w43a with the same result.

I have seen this on another seed as well. I've only created a few maps so maybe this is common?