The dispersion and loss of helium inside a single-car residential garage attached to a single-family house was experimentally characterized by recording time-resolved helium concentrations at multiple locations in the garage and at a single location in the house during and following helium releases near the floor of the garage. Helium served as a surrogate for hydrogen for safety reasons, and helium release rates were adjusted to provide the same constant volume flow rate as that required to release 5 kg of hydrogen over a four hour period.