The Canadian Coast Guard Rescue Station in Cobourg’s harbour is past its service life and requires replacement. Designed to Passivhaus standards, the new structure will have a highly air tight and heavily insulated walls and high performance windows. The summer cooling demand is expected to be near zero, with solar shading and an extended phase shift due to the insulation levels keeping the structure cool in summer months. Similarly the shoulder seasons will require minimal heat with most energy coming from passive solar gain, and the building will be kept frost-free in the winter off season with no energy. With the minimal energy inputs coming from electricity, the building will emit zero emissions.