Many believe Faulkner made a mistake in describing Sutpen's house as built of brick at the beginning of the story, but in describing the fire that destroyed it we are made to see a wooden house burning to the ground.
This was no mistake. Consider the fall of Sutpen. He built a brick house, big as a courthouse, when he came as a symbol of his power over the people around him. A common wooden house would never suit Sutpen as we first know him. By the end of the story Sutpen is destroyed with no hope of redemption. A brick house, with walls yet standing, might be rebuilt. The end of the house must be as the end of Sutpen.
Consider that after Absalom, Absalom was first published Faulkner had several chances in subsequent editions and printings to change the description of the house. He didn't. He let that house, as a symbol of the man, change just as the man changed and end as the man ended.