On chilly winter days in New York City there’s a common occurrence that strikes despair into the hearts of energy-efficiency experts: residents of steam-heated multifamily buildings using “double-hung zone valves”—better known as windows—to solve overheating problems.
According to Dan Holohan, a retired consultant with extensive knowledge of steam heating systems who is quoted in Bloomberg News, that’s what steam heating systems were often designed to do: create warm enough apartments that occupants could open their windows even in winter to allow for ventilating them with fresh air. Apparently many of these steam heat systems were installed in the first few decades of the 20th century, and their designs were influenced by that era’s understanding of public health and particularly how to combat the spread of such scourges as the influenza pandemic of 1918–1919.
Get caught up to today’s understanding of how to retrofit steam-heated multifamily buildings and provide effective ventilation with a recent talk at the international Passive House Institute’s conference by Stefan Oehler of ecoworks, based in Berlin. His firm renovated three 90-year-old multifamily buildings in Hamelin, Germany using an Energiesprong approach with prefabricated exterior façade panels. These façade panels included windows, mineral wool insulation, sun blinds, heat-recovery ventilation systems, and more. With a little practice, the façade company was able to install each panel in 20 minutes. You can get access to the talks until November 1 here.