GB 50189-2015 第3.4.1条
| **** | **Exterior window air tightness**: The air tightness grade of exterior windows and open balcony doors shall not be lower than Grade 6 as specified in the national standard GB/T 7106 "Graduations and Test Methods for Air Permeability, Water Tightness and Wind Load Resistance Performance of Building Exterior Windows and Doors" (i.e., air infiltration per unit joint length q1 ≤ 1.5 m³/(m·h), air infiltration per unit area q2 ≤ 4.5 m³/(m²·h)). |