This standard specifies the laboratory method for determining the air permeability of door and window assemblies when subjected to positive or negative air pressure. It details the test apparatus, procedure, and calculation method to quantify air leakage, which is a key performance indicator for energy efficiency and weather-tightness of building envelopes.
Specifies a method for determining the air permeability of doors and window assemblies.
Quick Reference Values
Test pressure applicationApplied in increments not exceeding 20% of the maximum test pressure
Pressure holding time per incrementat least 10 seconds
Pressure measuring device accuracywithin ±2% of the maximum reading
Pressure application directionBoth positive (inward) and negative (outward) pressures are applied
Key Formulas
q = V / L — Air permeability per unit length of opening joint (m³/h.m)
q_A = V / A — Air permeability per unit area of the specimen (m³/h.m²)
Practical Notes
The maximum test pressure for a project is derived from the design wind pressure calculated as per IS 875 (Part 3), considering building location, height, and topography.
This part (Part 4) only covers resistance to static pressure. Other performance aspects like air leakage and water penetration are covered in other parts of the IS 13362 series.
Careful sealing of the test specimen in the chamber is critical to avoid leakage and ensure accurate pressure application on the assembly's face.