How Mongols Survive -40°C in Felt Yurts Without Freezing

The felt on a Mongolian ger covers the walls and the roof, and in a University of Pennsylvania model of a plain ger, those carry 40 percent of the heat loss. About a quarter leaves through the seam where the felt wall meets the floor, sealed the traditional way with canvas and piled dirt. In the winter of 2018 to 2019, a Penn team working for UNICEF, alongside GerHub and KieranTimberlake, metered six gers on a plot outside Ulaanbaatar they called the Ger Ranch. The plain one would need about $600 of electricity to get through a winter. Light the coal stove and the cold air leaking in roughly doubles, because every bit of air carrying smoke up the chimney gets replaced through the gaps. This video follows the heat out through all five exits: the walls and roof, the floor seam, the gaps, the crown, and the door. Also in here: why three floor fixes failed at the edge, the insulated door cover that took one family from three coal firings a day to two, a Georgia Tech thesis that puts leaking air at 0.183 percent of the heat loss, the 4 to 8 metric tons of coal a typical ger-district family burns in a winter, and the everything ger that came in around $325 a winter on electricity. If this kind of building physics breakdown is useful to you, more here:    / @themeasuredhouseyt   Sources cited: Braham, Oskierko-Jeznacki and Hakkarainen, Designing the 21st Century Ger: Monitoring and Diagnostics 2018-19, University of Pennsylvania for UNICEF, 2019. University of Pennsylvania Weitzman School, Designing the Ger of the 21st Century 2018-19, project page. Hakkarainen, Grey-box Modeling to Evaluate Heat Loss in Mongolian Ger, Georgia Tech. KieranTimberlake, Designing the 21st Century Ger, project page. Sarangerel, The Potentials for Bioenergy Development in Mongolia, Ministry of Fuel and Energy, Mongolia. New videos Tuesday, Thursday, Saturday.