This research investigates the air permeability and watertightness performance of commercially available windows and doors based on laboratory tests conducted in accordance with the EN 1026 and EN 1027 standards. All tests were carried out under controlled environmental conditions, and the results were validated following relevant ISO procedures to ensure reliability and consistency. The tests are essential for evaluating the air permeability and watertightness of commercial windows and doors to ensure the overall performance, energy efficiency, and durability of the building envelope. The results provided consist of 244 samples (93 doors and 151 windows) tested between 2018 and 2025 in an accredited laboratory complying with EN ISO/IEC 17025. The results show that most doors achieved the highest air permeability class (Class 4) according to EN 12207, with shares ranging from 50% to 80% and exceeding 65% in most years. Window performance was similarly strong, with more than 74% of samples classified as Class 4, indicating consistently high airtightness and compliance with stringent energy efficiency requirements. Watertightness tests revealed that 59% of products were resistant to water penetration, while 41% were permeable. Among watertight products, windows predominated (67%), while doors accounted for a larger share of water-permeable cases. The results support informed decision making in manufacturing, construction practices, and early-stage building design, contributing to improved building durability and energy efficiency.
Jucienė et al. (Fri,) studied this question.