Thermal bridge detailing in tunnel form buildings with passive house principles

Yılmaz, Derya
As a result of depleting fossil fuels, increased energy prices and global warming, the growing importance of energy efficiency given birth to spread construction of energy saving buildings and use of new technologies around the world. Since thermal bridges in buildings may cause excessive heat loss, mold growth and deterioration of indoor air quality; to eliminate thermal bridges becomes very crucial both in existing buildings and in energy efficient buildings. In this thesis, energy demand of a six storey tunnel form social housing unit in Ankara is calculated using Passive House Planning Package. Later on, the energy demand of the building is reduced applying Passive House Principles. The impacts of thermal bridges on energy demand of the baseline building and Passive House building are compared by evaluating six construction details including balcony, basement wall, roof, floor slab, interior wall and corner detail. Thermal bridge calculations are carried using Therm 6.3 Software. Since the results indicate that the fraction of the transmission heat losses is highest in the balcony, balcony detail is studied in more detail to show the impacts of improved detailing on annual heating demand. Application of Passive House principles results in up to 82% reduction in annual heating demand and up to 57% reduction in primary energy demand. In the baseline building, the impact of thermal bridges, as the percentage of the total annual heating demand, is small (5%). As properties of the thermal envelope are improved, the impact of thermal bridges is also increased (up to 14%). The amount of heat losses through thermal bridges is highest at the balcony, unheated basement wall and roof detail respectively for the both cases. Floor slabs and interior walls are the places where most of the total fabric conduction heat losses occur in the building. To insulate the balcony floor slab above and below the slab can reduce the thermal bridge heat losses by 32%. To use a thermal break element can reduce the thermal bridge heat losses by 84% and increase the minimum surface temperature significantly ensuring a detail without the risk of structural damage.
Citation Formats
D. Yılmaz, “Thermal bridge detailing in tunnel form buildings with passive house principles,” M.S. - Master of Science, Middle East Technical University, 2014.