Aluminium Curtain Walling: Design and Installation

Aluminium Curtain Walling: Design and Installation

Aluminium curtain walling is now common in modern architecture for its streamlined looks, long-lasting durability and versatility. And as an external cladding system, which is literally defined as hanging curtain style from a building’s structural frame, it serves its purpose quite well aesthetically as well as functionally. These curtain walls provide comfort, weather resistance and thermal insulation. This makes them perfect for commercial high-rise buildings, office buildings and simple modern residential structures. Nevertheless, the installation must be done with accurate precision and the design must be well thought out. This guide outlines the most important factors needed in both phases for the installation of an aluminium curtain wall system that is long-lasting and of high quality.

Core Design Considerations

The design of an aluminum curtain wall is crucial because it combines artistry and practicality while ensuring safety and legal compliance. Several of them should be paid attention to during the design phase. 

Most importantly, the structural integrity of the wall is critical. All curtain walls are subjected to varying levels of weight, tilt and tension, and so must resist the constant barrage of the elements like wind, earthquakes, and gravity, to name a few. When a structure is built, engineers must take the time to conduct wind load calculations on the structure, based on its altitude, surroundings, and the immediate area, such as coastal buildings. These structures must be designed to resist more vicious winds along with salt erosion. For structural support, the frame is mostly made from the high-strength aluminum alloy 6063-T6. Also, the connectors and fasteners must be able to withhold the specified load, without bend deformation.

In today's construction, the effectiveness of an energy system and thermal functioning are important. However, aluminum can transfer heat quite easily. For this, thermal breaks, although typically made of insulating materials like polyamide, are integrated into the frame to reduce energy consumption related to heating and cooling. Also, the glass selection does matter: Low-Emissivity (Low-E) argon glass double/triple glazing provides enhanced thermal insulation. The design also includes certain features to allow thermal expansion and contraction of aluminum, like expansion joints, to prevent the material from bending and breaking thermally and during daily temperature shifts.  

As for the construction, an extreme boundary should be set for the aluminum skin. This should be conducted to have finer control of the building’s internal environment. The construction possess releasable water and are resistant systems. A recent trend is the pressure-equalized rain screen (PERF) which does this very managed and managed. This is the thermal expansion and contraction of aluminum slabs. It also offsets the inner air pressure and prevents the building from being ‘sucked’ in to. For chemical reasons, sealants should not be left between aluminum joints. The chemical sealants should not be aluminum to joints and frames. This reaction should be monitored to prevent deterioration.

Last but not least, the exterior appearance and divisional customization must be coherent with the rest of the architectural design. Aluminium curtain walls allow for anodizing, powder coating, and wood-like finishes. anodizing, durable and resistant to corrosion, comes in different metallic colors. While powder coating anodizing is more colorful, it is solid and has no variety in tone. The design team must also consider how the curtain walls sightlines work against one another. With unobstructed views, narrow frame profiles maximized the glass area. While thicker profiles are not as popular, they provide a more unobscured and industrial look.

Key Installation Processes

Without proper installation, a well-designed aluminium curtain wall system is bound to fail. Each step in the installation process is important, requiring a certain skill level, safety measures, and quality control.

The first phase of installation is preparation and site setup. No components should be delivered until the structural frame of a building is checked and confirmed to be level, plumb and within the specified tolerances. If these tolerances are not met, the curtain wall is prone to misalignment, hence shims and other adjustments are added. For curtain walls in high rise buildings, safety measures such scaffolding, edge protection, and harnesses are employed. After preparing the site, the components of the aluminium frame, the vertical mullions and the horizontal transoms, are appropriately stored in dry shelter to avoid debris.

The next step involves fastening the main frame in place. The first work step involves fastening the mullions to the structural slab or beam of the building using the brackets assigned to each. The brackets you're using are bound with bolts, for which their placement is a matter of vertical alignment using laser levels. Subsequently, the mullions are tied to the transoms creating a mesh which would serve as the frame to support the glazing and aluminium panels. The structural frame members also have to be set with uniform distances, as in the final design, so that the system being built can support loads without buckling. During this step, the correct thermal breaks are applied to the frame in order to keep the system's energy performance at peak levels.

Step three is about fitting the aluminum panels and glazing. For big constructions, cranes or hoists lift the panels. For smaller constructions, the panels are placed by hand. Every panel is positioned and locked onto the frame via screws or clips. Gaskets as placed between the frame and panel to make sure the seal is weathertight. With glazing, glass units are placed in the frame and are secured with glazing beads or structural silicone. The trim is part of the uniform seal. The silicone seal is applied meticulously to avoid water ingress. Excess seal is removed to create a polished look. Breakage and scratches must be avoided on aluminum panels and glass. 

In the end, all systems are checked and tested to confirm that the desired performance is reached. Fasteners that are still visible and pose as a danger to the esthetics are covered with caps. The whole curtain wall is also cleaned to get rid of debris from the construction. During the testing phase, we conduct water penetration tests. This is where we shoot the wall with water at high pressure. We also test for, air which is leaking out of the wall. These tests are done to see the curtain wall aligns with the regional building requirements and the design.

Quality Control and Maintenance

Ensuring the installed curtain walls are properly functional & maintained is the main perquisite for its performance & longevity. 

The AU frameworks, glass, sealants, & other mechanisms should meet to the slab arrangement & the regulatory standards. No Sealants dents, scratches, or cracks should be visible. For the adjacent units, inspections should be constantly held & documented to keep track of performance standards. Important steps to an extent should be photographed to resolve them later. 

The sealants should be checked at least once a year for cracks, since older ones tend to leak, & the unit should be removed, cleaned, & then be re-sealed.Also, every 3-5 years, structural elements should be checked. This includes brackets, bolts, and frame members for corrosion, particularly in coastal areas of salt air. All corroded pieces should be cleaned and treated with anti-corrosion coating, or replaced if damage is severe. Sealed glazing, especially for fa?ade units with panes of glass, is critical. Fogging that occurs and stays between panes is a sign of a failed seal, which diminishes insulation capacity. Fogging glass units shouldn’t be left in place for long, or other damage may be caused.