I tried to build a fireplace out of brick and contained it inside a fireplace structure. The house was built out of wood and caught fire. I tried a little experiment by re-lighting the fire in the fireplace and the roof caught fire after roughly 15 seconds. Wood just touching the brick while the netherrack was lit burst into flame. This is really annoying as I'd like to create a fireplace without my house catching fire. I tried it with one block of netherrack and it lasted and the house didn't seem to catch fire, but as soon as I made it bigger with three blocks of netherrack, trouble started. Please look into this. Thanks!