Analysis of the compliance of windows with up to day energy efficiency requirements

Abstract

Due to the consequences of the energy and environmental crises, reducing energy consumption in buildings is an urgent task, both globally and nationally. It is this goal that causes a constant increase in the requirements for resistance to heat transfer of the external enclosing structures of buildings in climatic conditions, where the design temperature of the outside air is at the level of -20ºС. Increasing the resistance of non-transparent enclosing structures is achieved by available means that allow guaranteed achievement of the designated resistance to heat transfer. Increasing the heat transfer resistance of transparent (or translucent) enclosing structures has limitations that limit the maximum values. The analysis of window designs that are offered on the construction market of Ukraine in the context of the requirements of DBN V.2.6.31-2021 "Thermal insulation and energy efficiency of buildings" was carried out. To increase the resistance to heat transfer of windows, the manufacturer has (today) three constructive means - an increase in the number of chambers, the use of selective coatings and filling the chambers with an inert gas argon. It should also be taken into account that the production of windows is a multicriteria task, in which the achievement of a certain level of resistance to heat transfer is one of the factors among others, no less important. The results of the analysis show that the fulfillment of the requirement Rqmin≥0.9 m2•ºС/W for the first temperature zone of Ukraine requires the use of all technical means available from manufacturers. A sample of eighty-two window designs that are actually offered on the Ukrainian construction market was analyzed. Compliance with the requirements for the second temperature zone was achieved for forty-three percent of window designs. Compliance with the requirements for the first temperature zone was achieved for seventeen percent of window designs. The complexity and increased cost of such structures may necessitate additional control measures at the completion of construction and during the operation of buildings.