
The defining feature of a French door is the glazed leaf. The glass unit determines most of the thermal, acoustic, and security performance.
Standard export units use insulated glazing units (IGU). Common builds:
Whole-door U-value (frame + glass) lands at 1.8–2.2 W/m²K for double glazing and 1.4–1.6 W/m²K for triple glazing, depending on the thermal-break width.
Tempered (Tempered Glass Standard EN 12150 / ANSI Z97.1) is mandatory for door leaves. Optional: Low-E coating, argon or krypton fill, laminated inner pane (PVB 0.76–1.52 mm) for safety and RW +4 dB, and tinted or reflective glass for solar control (SHGC 0.25–0.45).
Single pane thickness runs 5 mm for standard and 6–8 mm for oversize leaves above 2.4 m height. Edges are seamed (C / J / pencil edge) before tempering. For coastal or school projects specify laminated 6+0.76PVB+6 to survive impact without shattering. Spacer is warm-edge Swisspacer or aluminum; warm-edge cuts condensation at the rebate by 30%.
A French door is a double door by geometry: two leaves on a shared frame. Sizing and hardware define the installation class.
Single leaf width: 600–1000 mm. Pair opening: 1200–2000 mm. Leaf height: 2100–2700 mm. Frame depth: 70–110 mm for thermal-break systems. Oversize leaves above 1000 mm need 2.0 mm wall thickness and reinforced mullion.
Multi-point locking (3–5 points) on a European groove (Euro groove 16 mm). Stainless steel hinges (304 grade, 2–3 per leaf). Optional: 3-star cylinder (EN 1303), anti-lift pins, and a flush pull handle. Hardware sets priced at $25–60 per door pair.
Three threshold profiles are offered: exposed (19 mm, lowest cost), rebated (15 mm, partial weather stop), and flush (0–12 mm, wheelchair-compliant, with drop-down seal). Flush thresholds need a drained frame and a complying sill pan; they add $12–25 per leaf but remove the step trip hazard at entry use.
French doors are used as front entry doors where the opening faces a garden, patio, or courtyard. The entry application adds security and weather-sealing requirements.
Entry French doors use EPDM gaskets on three chambers, a drop-down bottom seal, and a threshold with thermal break. This reaches water-tightness class 4–6 (350–700 Pa) and air-tightness class 7–8 per GB/T 7106 / AAMA.
For entry use, specify laminated inner glass, a PAS 24 compliant multi-point lock, and hinge-side security pins. See our steel security door specs for the locking standard we apply across the exterior range.
As an interior glass door, French doors divide living and dining spaces or close a home office while keeping light flow. Interior units drop the weather rating but keep the glazed look.
Interior French doors use a narrower frame (50–70 mm), single or double glazing without thermal break, and a lighter hinge. Wall thickness can drop to 1.4 mm. Price for interior units starts at $110/m².
Interior laminated glass (5+0.76PVB+5) reaches Rw 34–38 dB, enough to close a home office. Exterior double glazing with argon reaches Rw 30–33 dB.
The frame finish is selected at order. Chinese factories keep 28 standard RAL colors in stock powder and match any RAL on request within 7 days.
Stock RAL: 9016 white, 7016 anthracite, 9005 black, 1015 pearl, 7040 grey. Anodized tones: champagne, bronze, black, natural silver. Powder cure is 180–200 °C for 10–15 min; film 60–80 μm with 1000 h salt-spray pass (ASTM B117).
Sublimation wood-grain (oak, walnut, teak) on the exterior keeps the aluminum body while giving a timber look. Transfer film bonds at 200 °C for 8 min; the grain layer is 20–40 μm and carries the same warranty as solid powder. Wood-grain adds $8–15/m².
Prices below are FOB China, per square meter of frame opening, excluding shipping and customs. They reflect 2026 export quotes from Foshan factories.
The frame is where Chinese aluminum door factories differentiate. The process runs: extrusion → aging → cutting → thermal-break insertion → surface treatment → assembly.
Primary alloy is 6063-T5 for profiles; structural millions use 6061-T6. Tensile strength 6063-T5: ≥160 MPa; 6061-T6: ≥260 MPa. All incoming billets are 99.7% primary aluminum with mill certificate.
Powder coating (AkzoNobel / Interpon class 1–2): film 60–80 μm, salt-spray resistance 1000 h (ASTM B117). Fluorocarbon (PVDF): 25–35 μm, 20-year color warranty. Anodizing: 10–20 μm (AA10–AA20). Coating cure: 180–200 °C, 10–15 min.
Strip material is PA66GF25 (polyamide 66 with 25% glass fiber). Width options: 14 / 18 / 24 / 34 mm. Insertion by roll-in process at 230–250 °C. Wider strip = lower U-value.
Cutting and routing run on 4-axis CNC at ±0.1 mm. Corner keys are screwed and two-component glued (not crimped only) for the premium line, raising corner shear to 2500 N. Drainage holes are laser-cut at a 5° inward slope to self-clear water. Each frame is dry-fit and square-checked before glazing.
These are the numbers buyers verify before ordering.
Export French doors carry region-specific marks.
Every door is checked before crating. The line follows 5S workshop discipline and a 100% full-inspection rule (not sampling) on critical items.
Checks cover frame squareness (≤1.5 mm over 2 m), leaf gap (3±0.5 mm), lock engagement, gasket continuity, and glass mark (tempered logo + CE/ANSI). A digital gauge records each leaf; the report ships with the container.
For Miami-Dade NOA projects the assembly is tested to TAS 201/202/203: large-missile impact (9 lb timber at 34 ft/s, 2 hits per bay), then 9000 cyclic pressure cycles at DP ±70 psf. Passing units are listed on the NOA and stamped at the frame. Budget 4–6 weeks extra lead for NOA documentation.
Terms for a typical Foshan export order.
Each leaf wrapped in PE foam + corner cardboard + bubble wrap. FCL shipped in wooden crate (plywood, ISPM-15 stamped). LCL consolidated on pallet with edge protector. Foam thickness 8–10 mm; crate rated for 800 kg.
Correct installation protects the warranty. The sequence below is the factory-recommended method.
Use a drained and vented frame; weep holes must stay clear. After fitting, run a hose test at 100 L/h·m² for 5 min — no leak at gasket or threshold. Commission by cycling each leaf 20 times and checking latch engagement.
A 320 m² villa in Queensland, Australia specified 14 French door pairs (total 56 m² of glazed opening) in a mid configuration: 1.8 mm wall, 24 mm thermal break, 5 Low-E + 12A + 5 double glazing, laminated inner pane.
The project saved 48% versus the local quote while meeting the same AS 2047 wind and water ratings. U-value measured 1.9 W/m²K on site.
Pick the tier by climate and budget.
For other exterior openings, see our entry door specs and pricing, the aluminum entrance door U-value tables, and the full aluminum door types and technical specifications overview.