GB/T 8478 Aluminium Windows & Doors: Grades Explained

What China's GB/T 8478 grades for air, water and wind performance mean in plain terms, and how export buyers should specify them.

Last updated: November 2, 2026

Windows & Fenestration · Last updated: 2 November 2026 · Jusen Doors Technical Team · Reviewed by Jusen Doors Engineering Team

GB/T 8478 Aluminium Windows & Doors: Grades Explained

Quick answer: GB/T 8478 is China's product standard framework for aluminium alloy doors and windows. For export buyers, its value is a common language for performance classification and test expectations—wind-pressure resistance, air permeability, watertightness, thermal and acoustic performance—rather than a substitute for the destination building code. Always name the current edition, required grade and product configuration in the purchase specification.

What the standard organises

GB/T 8478 covers terminology, classification, technical requirements, test methods, inspection rules and product information for aluminium alloy doors and windows. It helps a buyer compare system families in China using shared performance language. A headline such as 'GB/T 8478 compliant' is incomplete unless the quote identifies the edition, series/profile, glass build-up, opening type and the grade claimed for each performance item.

Performance grades need a test specimen

Air, water and wind results belong to the tested size and configuration. A small fixed window can achieve a different class from a large sliding door using the same nominal profile family. Thermal performance also depends on glazing, spacer, thermal break and frame ratio. Ask for the test report's specimen drawing and compare it with the largest or most exposed unit in the order—not just the easiest catalogue size.

Translate requirements to the destination market

A GB/T grade may help pre-select a system for North America, Europe, the Middle East or Australasia, but it does not replace local energy, structural, safety-glazing or cyclone requirements. Convert the project loads and energy targets into performance criteria, then ask whether prior GB/T, EN, ASTM/AAMA or AS test evidence covers them. Treat conversions between pressure classes and test methods as engineering comparisons, not automatic equivalences.

Specify profiles and hardware, not only grades

Aluminium performance is a system result: alloy/temper, wall thickness, thermal-break design, corner joining, drainage, gaskets, glass bite, hardware and installation all matter. Drawings should state the profile series and finish system. Our powder coat vs anodized vs PVDF guide covers the exterior finish decision that GB/T performance grades do not settle by themselves.

Procurement checklist

Current GB/T 8478 edition and claimed performance grades.
Test specimen size, opening type and glass build-up.
Profile drawings, alloy/temper and nominal wall thickness.
Thermal-break and drainage details.
Finish type, film/anodic specification and colour tolerance.
Destination-market tests or calculations still required.
Installation and perimeter-sealing responsibility.

Specification checklist: what to confirm before ordering

Destination code, climate/wind exposure and compliance route fixed before product selection.
Operator type, maximum size, frame system and glass build-up matched to test evidence.
Structural, water, air, thermal and safety-glazing duties specified separately.
Labels, calculations and submittal documents required at permit/inspection.
Anchorage, flashing and perimeter sealing responsibilities assigned.

Related guides

Sourcing windows or aluminium doors for a project?
Send the schedule, target market, performance requirements and largest unit sizes for a system review.
Request a specification check · Browse the guide hub

FAQs

Does GB/T 8478 compliance make a window legal in the US or Australia?

No. It is a Chinese product/performance framework. Destination codes and standards still govern structural, energy and safety acceptance.

Why do two windows with the same profile have different grades?

Size, opening method, glass, hardware, reinforcement and drainage change the result. The tested specimen matters.

What should appear on the quotation besides the standard number?

Edition, grade for each performance item, profile series, sizes, glass build-up, finish and inclusions.

Data note: Figures described as typical, common or planning ranges are industry budgeting ranges with the stated assumptions. Building-code duties, tested scope and final quotations depend on destination, selected construction and order schedule.