Analysis for Thermal Effect by an Unheated Housing Unit in Apartment

공동주택에서 비난방세대가 미치는 열적 영향

  • Received : 2015.01.06
  • Accepted : 2015.12.11
  • Published : 2016.01.10


Adjacent housing units suffer inevitable thermal losses if an unheated unit exists in an apartment building. Thermal loss of the units adjoining the unheated apartment can be neglected because the contact area is small and insulators are located in the walls. When insulators are not included in the slab between the upper and lower units, 70% of the heat supplied by an Ondol system may be used in the original unit, but 30% is transferred to the unit on the lower floor. Another 30% can be obtained from the ceiling if the upper floor housing unit is heated. This strong thermal connection is a characteristic of Ondol heating in apartment buildings. When there is an unheated unit, the lower floor unit uses 42.3% more heating energy if there is no insulation and 19.5% if a 35 mm insulator is used as in the current guidelines. Therefore, much thicker insulation should be applied to weaken the thermal connection.


Heating energy;Ondol;Insulation;Apartment house;Heat loss;Thermal connection


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