Role of airtightness in energy loss from windows: Experimental results from in-situ tests


Cuce E.

ENERGY AND BUILDINGS, vol.139, pp.449-455, 2017 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 139
  • Publication Date: 2017
  • Doi Number: 10.1016/j.enbuild.2017.01.027
  • Journal Name: ENERGY AND BUILDINGS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.449-455
  • Keywords: Double glazed windows, Heat loss, Air leakage, Airtightness, U-value, Energy saving, INSULATION SOLAR GLASS, ACOUSTIC PERFORMANCE EVALUATION, LOW-CARBON BUILDINGS, AIR-TIGHTNESS, GLAZING TECHNOLOGIES, FUTURE-PROSPECTS, CONSUMPTION, HOUSES
  • Recep Tayyip Erdoğan University Affiliated: No

Abstract

The rate of air leakage related energy loss from glazed areas is unequivocal especially in older and poorly installed windows. Therefore, in this research, a comprehensive experimental investigation is done to analyse the importance of air leakage on overall heat transfer coefficient (U-value) of conventional air filled double glazed windows. The tests are conducted in a typical UK dwelling of Nottingham fitted with traditional air filled double glazed windows. One sash of the test window is sealed internally with a special transparent cover to provide excellent airtightness whereas the second window sash is left as it is to represent the ordinary case. The experiments are conducted in April 2016, and dynamic co-heating test methodology is applied to evaluate the rate of enhancement in the U-value of airtight window sash. The results indicate that the airtight window sash has a notably lower U-value compared to the ordinary window sash due to the impact of airtightness and reverse heat flux during noon time owing to the greenhouse effect between transparent cover and internal glazing. The overall U-value of ordinary window sash is found to be 2.67 W/m(2)K, whereas it is 1.79 W/m(2)K for airtight window sash. It is observed that about 33% of reduction in heat losses can be achieved via airtight windows. (C) 2017 Elsevier B.V. All rights reserved.