When you compare aluminum casement windows from different factories, one specification appears again and again: profile thickness. On the C113 outward-open window, the profile wall thickness is 1.8–2.0mm. Understanding what that number really means — and what it does not mean — is the key to choosing a window that stays straight, fully sealed, and energy-efficient for decades.
Profile thickness is often confused with frame width, but the two are completely different measurements. On the C113 outward-open window, the frame width is 113mm, which is the overall depth of the frame and largely determines how the window looks and how much glass it can carry. The profile wall thickness of 1.8–2.0mm, on the other hand, is the thickness of the aluminum wall itself. It determines how much load the frame can bear before it flexes or deforms.
Two windows can look identical from the outside yet perform very differently. A thin-walled profile will twist and sag under wind pressure or heavy glass, which eventually breaks the seal between frame and sash and lets air and water in. A correctly specified wall thickness keeps the frame rigid, the seals compressed, and the window operating smoothly for years.
1.8mm is the minimum wall thickness required by the current national standard for residential aluminum windows (GB/T 8478-2020). The C113 outward-open window is manufactured with 6060-T66 grade aluminum profiles at a 1.8–2.0mm wall thickness, so it meets or exceeds the latest standard rather than merely matching an older, thinner specification.
6060-T66 is a heat-treated aluminum alloy known for high strength and excellent corrosion resistance. Combined with a wall thickness of 1.8–2.0mm, it gives the C113 enhanced structural rigidity and deformation resistance, so the frame holds its shape even in large openings and in regions with strong wind loads.
| Profile Thickness | 1.8–2.0mm |
| Profile Grade | 6060-T66 |
| Insulation Strip | PA66GF25 |
| Frame Width | 113mm |
| Glass Sash Thickness | 57mm |
| Mullion Width | 75/21mm |
| Opening Method | Outward Opening |
| Screen Mesh | Black High-Definition Anti-PM2.5 Mesh |
Profile thickness alone does not make a window warm. The C113 combines its 1.8–2.0mm walls with a PA66GF25 thermal break insulation strip and a multi-chamber profile design, so the frame stays warm in winter and cool in summer. The glass centerline, thermal break strip, and equal-pressure sealing strip are aligned on the same axis, which keeps the insulation line continuous across the whole window.
On top of that, the C113 uses a triple sealing defense that blocks wind, rain, noise, and extreme temperatures. The full glue-injection process, with integrated glued corner brackets, creates a seamless monolithic frame, so there are no weak points at the corners where water and air commonly find their way in.
Strength is only useful if the window is also easy and safe to operate. The C113 outward-open window is fitted with CMECH hardware, a German Red Dot Design Award winner, tested through 30,000 opening cycles. The combination of a rigid 1.8–2.0mm profile and precision hardware means the sash stays aligned, the locks engage cleanly, and the window keeps its smooth action over a long service life.
When you specify windows for a project, start with the local wind load and the size of the opening. For standard residential openings, a 1.8mm wall thickness is the baseline required by current standards. For larger sashes, coastal areas, or high-rise buildings, choose a thicker wall (2.0mm or more) and confirm the frame depth and glass configuration with the factory.
Also check the grade of the aluminum. A thick profile made from low-grade alloy will not perform as well as a correctly specified 6060-T66 profile. Ask your supplier for the exact alloy grade, wall thickness, and thermal break details before you place an order.
As a professional casement window manufacturer and casement window supplier based in China, ALPES produces system windows and doors in a 100,000 m² manufacturing facility with two production centers in Foshan and Zhaoqing, Guangdong. The C113 outward-open window is manufactured according to international building codes, and direct-from-factory pricing makes it a competitive choice for high-end residential and commercial projects.
Every C113 window is built with 6060-T66 profiles, PA66GF25 insulation strips, and CMECH hardware, and it can be finished in Ice Cream White, Aurora Gray, Starry Sky Gray, or Brown Coffee, with custom color matching available on request.
If you are planning a project and want to compare the C113 outward-open window with other options, contact the ALPES team for the latest casement window price and lead times. The team can recommend the right profile thickness, glass configuration, and hardware for your climate and opening sizes.
