A modular vivarium is constructed entirely from transportable, sterile modules of distinct types, called pods. A hallway pod forms a spine, with cage-rack pods, ingress/egress pods and optional VHACPIT pods providing HVAC, power and IT services connected as spur pods to the hallway. Supplies and waste are also within modular pods. Temporary or single-use seals cover doorways during transit. Modules are joined or removed while maintaining sterility on both sides of the flush-to-wall doorway junction. Supply and return air for all pods is through hallway based ducting. Pods may be constructed from ISO intermodal containers. Embodiments have no permanent buildings. Pods may be moved, leveled and aligned for joining via special supports. Cage-rack pods are configured with two cage racks and a single isle permitting robotic cage placement and retrieval. Embodiments provide vibration, noise and earthquake isolation.