GB/T 31127

EXECUTIVE SUMMARY

This report covers GB/T 31127-2014, a TIER 2 field test method for installed building exterior windows/doors (建筑外门窗气密、水密、抗风压性能现场检测方法). The standard is current and has no direct international equivalent — field testing is governed by ASTM/AAMA in North America and is non-harmonised in Europe. The key procurement implication: Chinese field test results are 不可互认 (Not mutually recognised) with lab-based international standards, requiring additional lab testing for export.

APPLICABLE CHINESE STANDARDS

STANDARD TIER CLASSIFICATION

FLAG: GB/T 31127-2014 is correctly used as TIER 2. It must NOT be compared against TIER 1 product standards (e.g. GB/T 8478) for equivalence — different tiers, different purposes.

SCOPE BREAKDOWN

Field testing of installed windows/doors (现场检测)

Chinese standard: GB/T 31127-2014: 建筑外门窗气密、水密、抗风压性能现场检测方法 (Field test methods for air permeability, watertightness and wind resistance of installed building exterior windows/doors)

International equivalent: ASTM E783-13 (Field Measurement of Air Leakage Through Installed Exterior Windows and Doors); ASTM E1105-15 (Field Determination of Water Penetration of Installed Exterior Windows, Skylights, Doors, and Curtain Walls) — ⚠️ no single international equivalent covers all three parameters

Equivalence: NEQ

Standard tier match: Both TIER 2 — valid comparison

KEY DIFFERENCES SUMMARY

• Test pressure for air permeability — CN uses 10 Pa vs ASTM 75 Pa; different method, 不可互认 (Not mutually recognised); HIGH impact.
• Wind resistance field test — required in CN, no ASTM field equivalent; 不可互认 (Not mutually recognised); HIGH impact.
• Sample size — CN requires ≥3 specimens vs ASTM ≥1; 附加测试后互认 (Mutual recognition after additional testing); MEDIUM impact.
• Scope coverage — GB/T 31127 covers 3 parameters; international standards split across ASTM E783/E1105; NEQ overall.

REGULATORY LINKAGE TABLE (法规联动)

AUDIT FLAG RESOLUTION

• ✅ RESOLVED: Standard identity — GB/T 31127-2014 is 建筑外门窗气密、水密、抗风压性能现场检测方法 (field test method), NOT a sealant standard. Answer A misidentified it as 建筑幕墙用硅酮结构密封胶 — corrected.
• ✅ FALSE POSITIVE: GB 16776-2025 — flagged as potential misapplication, but valid as related sealant standard in the fenestration family; cited as TIER 1 product standard only.
• ⚠️ UNRESOLVED: Exact clause numbers for test pressures — verify against GB/T 31127-2014 official text.

PROCUREMENT VERDICT

• Confirm GB/T 31127-2014 is the correct standard for field testing — do not confuse with sealant standards.
• For export to North America, plan for ASTM E783/E1105 field testing in addition to CN testing.
• For EU export, note no harmonised field test standard exists — use EN 1026/1027 lab testing.
• Verify clause numbers in official GB/T 31127-2014 text before contract signing.
• Ensure ≥3 specimens per CN requirement; budget for additional samples.
• Engage a licensed inspection engineer (注册监理工程师) for on-site test witnessing.

REFERENCE DOCUMENT CHECKLIST (配套调阅清单)

• GB/T 31127-2014 §5.3 — sample selection quantity
• GB/T 31127-2014 §6.2 — air permeability test pressure
• GB/T 31127-2014 §7.2 — watertightness test method
• GB/T 31127-2014 §8.2 — wind resistance field measurement
• ASTM E783 §8.2 — air leakage test pressure

FIELD INSPECTION CHECKLIST

• Verify installed window/door type matches GB/T 8478 product spec.
• Confirm test specimens are representative of installed batch (≥3 units).
• Check test equipment calibration certificates are current.
• Witness air permeability test at 10 Pa differential per CN method.
• Document water penetration results with photos for mutual recognition evidence.
• Verify sealant type matches GB 16776-2025 if structural glazing is involved.

CONFIDENCE RATING

🟡 MEDIUM CONFIDENCE — core data verified, ≤3 parameters flagged for official text confirmation (clause numbers for test pressures and methods). Standard identity confirmed via official registry.