What is the symbolism of Harvey and Perry’s childhood home in the novel, Northern Lights?

Set just outside of Sawmill Landing, Harvey and Perry’s childhood home is an essential symbol in Northern Lights. The home—once owned by their father—is simple, practical, and unadorned. Before his father’s death, Harvey constructed a sturdy bomb shelter in the backyard. As the narrative progresses, both the house and bomb shelter emerge as clear symbols of the past. Perry, by the end of the novel, decides to sell the house and to move away from Sawmill Landing; in this way, Perry looks towards the future. Harvey, himself the constructor of the bomb shelter, remains attached to the home. Unlike Perry, he is unwilling to set aside the memories and emotional burdens that linger there. In this way, the house and the bomb shelter act as a central point of divergence in the relationship between Perry and Harvey.