Direct answer. Budget 10 to 20 weeks of factory time and expect USD 160–320 per m² FOB China for a unitized curtain wall system, before glass upgrades. The supplier matters more than the price. Around 90% of a unitized wall is assembled in the factory, so tolerance control and mock-up test evidence decide whether the facade leaks.
What to screen before you ask for a price
Three checks cost nothing and remove most weak candidates.
- Business licence and factory address. Confirm the registered address is the production site you intend to audit, not a sales office in another city. The name on the quotation does not always name the party that manufactures.
- Comparable systems, with references. Ask which recent projects used the same system you are pricing. A supplier with no comparable reference is a design risk, not a price advantage.
- ISO 9001 scope. Ask for the scope wording, not just the certificate. A certificate covering "trading of building materials" says nothing about manufacturing control.
Engineering: who actually signs the calculation
A unitized wall is an engineered system, not a commodity. Establish, in writing, who is responsible for structural calculations, wind-load assessment, mullion sizing, anchor reactions, glazing calculations, thermal calculations and movement allowances. In-house engineering is not automatically better than an external facade engineer — the test is whether responsibility and review are documented and whether the final technical package has a named signatory.
For North American projects, confirm whether the supplier's engineering is reviewed or sealed by a licensed Professional Engineer (PE) in the project's state. PE licensure is granted state by state, and a licence from one state does not authorise sealing drawings for another.
Manufacturing control, tolerances and test evidence
For unitized production, assembly and glazing are the heart of the factory. Ask for the process sequence — cutting, machining, frame assembly, glazing, gasket installation, final inspection, packing — and the inspection record at each stage. Then ask the harder question: which tolerance applies to which component, where it is defined, and how it is measured.
Performance claims should be tied to specific test methods and to your configuration:
| Parameter | Test method | Typical acceptance criterion |
|---|---|---|
| Air infiltration | ASTM E283 | ≤0.3 L/s·m² at 300 Pa |
| Static water penetration | ASTM E331 | No uncontrolled leakage at 720 Pa |
| Dynamic water penetration | AAMA 501.1 | No leakage at design wind pressure |
| Structural (wind) load | ASTM E330 | No damage at 1.5× design load; deflection to L/175 |
| Seismic inter-storey drift | AAMA 501.4 | System accommodates design drift without damage |
A test result from a different mullion size, joint arrangement or glass build-up is reference information, not proof of project compliance.
Factory audit and export documents
Walk the factory in process order — billet intake, extrusion, machining, assembly and glazing, QC station, packing. Ask to pull three inspection records at random from three different months. Paperwork either exists as a habit or it does not. Before shipment, confirm the packing method (stillages, corner protection, moisture control), the loading sequence and who carries responsibility for damage, spare units and replacement panels. Specify an independent pre-shipment inspection if the project warrants it.
Where QIMU fits
QIMU FACADE GLOBAL is a Hong Kong-headquartered curtain wall supplier with manufacturing in Changzhou, China and Kapar, Malaysia. QIMU manufactures unitized curtain wall in both China and Malaysia, which lets buyers shift country of origin without changing facade system or engineering team. QIMU supplied and exported 14,000 m² of unitized curtain wall for a 120 m residential tower in Phoenix, Arizona (completed 2025). The Changzhou manufacturing base has produced facade work since 1986, and the project record covers North America and China, including unitized curtain wall delivered to Chicago, Atlanta and St. Louis.