The invention provides a building assembly comprising a subterranean cellar defining a space to be formed under the ground, the cellar having a ceiling including a first opening defining an access region for a staircase to connect the ground of the subterranean cellar, when in situ, with the surface of the ground above the cellar; and a heat control device having a heat transfer mechanism to provide heat from the cellar to a region on the ground above the cellar.

A modular well cellar system can include a planar base member defining an aperture sized to receive a conductor pipe; a first end member secured to the base member and configured to support a first lateral wall of the well cellar excavation; a first side member secured to the base member, the first end member, and the second end member, and configured to support a first longitudinal wall of the well cellar excavation; a second side member secured to the planar base member and the first end member and configured to support a second longitudinal wall of the well cellar excavation; and a seal formed between a top surface of the planar base member and each of the first end member, the first side member, and the second side member.

An underground room arrangement, comprising a structure surrounding a room, the structure comprising a plastic tube and plastic end walls, wherein the plastic end walls are arranged to close the plastic tube so that inner surfaces of the plastic tube and the plastic end walls are towards the room.