Specifying aluminum windows and doors for a 2026 build starts with five hard gates: profile aluminum alloy temper, thermal-break architecture, glazing thickness, hardware cycle rating and project climate band — the order in which these are answered decides whether a quote at US $5.50–13 per square metre (FOB China, sliding impact-grade, factory-direct tier, 2026-06-25) is even comparable against a competing bid [S4].
Buyers comparing two quotations from Shandong Imagery Aluminum Technology or Delanshini should not be looking at headline unit price first — they should be looking at whether the profiles on offer are 6063-T5 or 6063-T6, whether the system is a thermally broken system window door or a non-broken frame, and what hardware grade the supplier is loading by default, because each of these flips the cost structure before any negotiation begins [S1][S2].
Profile Alloy & Surface Treatment: 6063-T5/T6 vs Anodized Stock
Aluminum window and door profile stock is dominated by 6063 extrusion, supplied either as mill-finish billet for the fabricator to cut and machine, or as pre-anodized profile — a 10-ton MOQ anodized profile quotation was logged at US $2,400 per ton with a 500,000-ton annual production capacity at one China mill (2016-12-20, factory-direct tier) [S3]. Anodizing film class (AA10 / AA15 / AA20 / AA25 per the AAMA/Qualicoat naming used by China mills) sets the UV and salt-spray budget; AA15 (~15 μm) is the residential default, AA20–25 is specified for coastal and high-rise curtain-wall applications.
For commercial jobs, ask the mill to disclose the temper certificate (T5 vs T6) and the anodizing class in writing; for residential, 6063-T5 is adequate in most climate bands, but 6063-T6 carries roughly 20–25% higher tensile/yield capacity and is preferred for large-span or hurricane-impact units such as the hotel-grade hurricane-impact sliding windows listed at US $5.50–13 per m² by Foshan Fuson Windoor Tech (2026-05-27) [S4].
Thermal-Break vs Non-Break: System Window Door Architecture
Thermal-break system window door profiles use a polyamide strip (typically 14.8 mm, 16 mm, 18.6 mm, 24 mm or 35 mm width) mechanically crimped or poured between the inner and outer aluminum shells to interrupt the conductive path; a wider polyamide width lifts the U-value, but also drives hardware pocket redesign and hinge mortise changes that the supplier must price separately [S1][S2].
Non-thermal-break frames remain standard for interior partitions, tropical climate builds and budget commercial projects where heating-load reduction is not a design driver. For projects targeting passive-house, near-zero-energy or simply code-minimum U-values in cold climates (North China, northern Europe, North America IECC zones 5–8), thermal-break is non-negotiable; verify the polyamide strip supplier (Technoform, Ensinger, AGC and domestic equivalents), because the strip grade — not the aluminum itself — sets the long-term thermal performance ceiling.
Glazing, Hardware & Hurricane-Impact Spec Cut
Glazing thickness in 2026 China-factory window SKUs clusters around 5 mm + 12A + 5 mm (22 mm insulated glass unit) for residential, 5 + 12A + 5 + 12A + 5 (33 mm double-IGU) for high-end residential and light commercial, and laminated 6.38 mm or 8.38 mm tempered glass on the storm face for hurricane-impact units [S4]. Hardware cycles must be quoted to a recognized grade — China domestic GB/T 8478 hardware, European Roto/Schüco/Siegenia cycle ratings (typically 20,000–60,000 cycles for hinges, 25,000+ for locking points), or ANSI/AAMA grades for export to North America — because a quotation that does not name the cycle target is not a real quotation, it is a placeholder.
Hurricane-impact aluminum sliders in the Foshan factory tier (US $5.50–13 per m², 2026-05-27) typically pair laminated 5 + 0.76 PVB + 5 or 6.38 mm tempered with a multi-point locking espagnolette and stainless-steel roller track; sub-grade substitutions here are the most common source of after-sales failure, so a side-by-side comparison gate for two competing impact-grade quotations is: glass build-up, hardware brand and cycle rating, drainage path design and weatherstripping bead count (typically two or three rows of EPDM) [S4].
Cost Levers, MOQ and Factory Tier Reality
The price spread quoted on 2026-06 listings is wide because the underlying specification is wide. Anodized profile stock at US $2,400/ton (10-ton MOQ) feeds small fabricators; a finished hurricane-impact sliding window in the US $5.50–13 per m² band is a finished, glazed, hardware-fitted assembly shipped FOB with the fabricator absorbing glass, hardware and packing into that number [S3][S4].
Shandong Imagery Aluminum Technology lists as a manufacturer/trading-company hybrid established 2013-12-03, which typically means it can either run its own extrusion lines or broker peer-mill tonnage depending on the order — useful for mixed-spec jobs but a risk for pure-spec jobs where the buyer wants a single mill of origin [S1]. Delanshini, by contrast, positions itself as a pure window/door fabricator with over 20 years of production experience, which is the right supplier type for a buyer who wants one warranty party for the finished assembly rather than an extrusion mill plus a separate glazier [S2]. For a procurement manager who needs comparable numbers from two different supplier types, the only fair cut is to normalize both bids to the same IGU build-up, hardware grade, anodizing class and surface-treatment warranty before looking at the dollar figure.
Climate Band, Use Case and Standards Mapping
Aluminum windows and doors are NOT the right pick for every project. They are a strong fit for: coastal/high-humidity builds (anodized AA20+), hurricane zones (laminated impact IGU + multi-point lock), large-span commercial curtain walls (6063-T6 + thermal-break + structurally glazed mullion), and minimalist residential where slim sightlines are a design driver [S4][S5]. They are a weaker fit for: ultra-low-budget interior partitions where uPVC or timber is cheaper per running metre, heritage districts where wood or steel is mandated by code, and any project where the buyer cannot verify the anodizing class and polyamide strip brand — the two most falsified items on a Chinese mill data sheet.
Standards that typically govern a 2026 aluminum window/door submittal include the China GB/T 8478 (aluminum windows), GB/T 8479 (aluminum doors) for domestic projects, AAMA/WDMA/CSA 101/I.S.2/A440 for North American export, EN 14351-1 for European CE marking, and the impact/cycle rating referenced in Miami-Dade TAS 201/202/203 for hurricane-zone projects. For spec-builders comparing aluminium-window sourcing with adjacent trades, the same five-gate logic (alloy/temper, thermal-break, glazing, hardware, climate) maps cleanly onto other 2026 procurement workflows such as the modified bitumen membrane 2026 buying guide, where the spec gate is carrier and modifier rather than alloy and thermal-break — but the discipline of normalizing bids to a fixed spec before price comparison is identical.