In Chapter 8 of The Great Gatsby, how has Gatsby's house changed?
It is clear that as Nick is unable to sleep and feels he needs to visit Gatsby to make sure he is OK, there is a definite change in the house. Consider what Nick says:
His house had never seemed so enormous to me as it did that night when we hunted through the great rooms for cigarettes. We pushed aside curtains that were like pavilions, and felt over innumerable feet of dark wall for electric light switches - once I tumbled with a sort of splash upon the keys of a ghostly piano. There was an inexplicable amount of dust everywhere, and the rooms were musty, as though they hadn't been aired for many days.
What is emphasised through this change is the vastness of the house - highlighting the emptiness of the space inside but also, implicitly, the emptiness of Gatsby's life. The dust and mustiness likewise reflect the fact that Gatsby's life and dream is over now - his house and its state represents his life. Now that he has decided to take the blame for Daisy for the death of Myrtle Wilson, he knows that all his hopes and ambitions have gone to dust, just like his house.
Gatsby's house that once was filled with guests and caterers, and later Daisy's presence, is now empty.
This abandoned house seems enormous and musty; even the furniture is covered with the dust of disuse. Such an appearance is in sharp contrast to the house as it has been described in Chapter Seven when Gatsby has had the role of Trimalchio, the Roman who gave lavish parties. Then the "restless crowds" flowed over the grounds amid long tables set up with delicacies and meats. This was the time when Daisy visited Gatsby and marveled at his gold fixtures and many fine English-tailored shirts.
Now, however, this musty house is deserted with its "ghostly piano" and dust-ridden furniture and floors. As Nick helps Gatsby search for cigarettes, he discovers a humidor on an "unfamiliar" table with "two dry cigarettes inside." Whereas before Gatsby's house generated freshness, music, and gaiety, in this chapter, the house is stuffy, dusty, and abandoned, haunted with memory and death-like silence.