If the house burns down because of that your insurer will likely be difficult about it. You should also check the policy of your insurer, perhaps the cause of the fire is irrelevant.

As for fire safety. I always put my electronics in non flammable environments and make sure that everything is fused with either a current or thermal fuse.

Anything with high current consumption goes inside a metal box so that even if it does catch fire it can't take anything with it. 3D printed enclosures are fine if you mount those inside a metal bucket for example.