The house in which Uncle Griffinskitch lived with his niece Kendra Kandlestar was built around the trunk of an old yew tree. Because of this, the floor plan was in the shape of a circle, with the trunk growing up through the middle. From the bottom floor, one could see straight up to the ceiling because of how the staircase spirals around the trunk, shooting off here and there to reach different rooms.

The kitchen was on the main floor of the house, and there was also a root cellar where food and other goods were stored. The bedrooms were on the upper floors and there were also many secret and private chambers where Uncle Griffinskitch studied and practiced magic. There were even rooms higher up in the tree, including an observatory at the very top, where Uncle Griffinskitch could gaze upon the stars and study the constellations. These higher rooms could only be reached by a very secret staircase, protected by spells and passwords, which spiraled up through the inside of the trunk.