Protection against atmospheric agents
Protection against atmospheric agents is a basic requirement for any window or door. It not only ensures thermal and acoustic performance, but also comfort, safety and the prevention of construction pathologies.
Air permeability | Cortizo aluminium and PVC windows for homes
Air permeability is the ability of a closed window to allow air to pass through when subjected to differential pressure, such as wind force. The applicable test measures the airflow passing through the sample during the test.
Air permeability classification
CLASS 1 < CLASS 2 < CLASS 3 < CLASS 4. These values show the amount of air that passes through a window over time and surface area. A Class 4 window is approximately three times more airtight than a Class 3 window, which in turn is three times more airtight than Class 2.
Watertightness
Watertightness is the ability of a closed window to resist water infiltration. The test consists of continuous water spraying while increasing pressure levels are applied until any penetration into the interior is detected.
Watertightness classification
1A < 2A < 3A < 4A < 5A < 6A < 7A < 8A < 9A < E750 < E... This classification evaluates the window’s behaviour against rain driven by wind pressure.
Wind resistance
The wind resistance test verifies that, under positive and negative pressures, the complete window maintains acceptable deformation, preserves its properties and guarantees user safety.
Wind resistance classification
C1 < C2 < C3 < C4 < C5. This classification is obtained by applying positive and negative pressures to determine relative frontal deflection and resistance to deterioration.