If you often travel through high-rise buildings, you must have found a special building exterior, which is an exposed frame glass curtain wall. The exposed frame glass curtain wall is like a huge piece of glass attached to the wall. Take a closer look, these glasses are not hanging there alone, but are firmly supported by a circle of metal frames-this is the “exposed frame glass curtain wall”. It is like the “transparent skeleton” of the building, which makes the building look fashionable and modern, and firmly withstands wind and rain. So what is an exposed frame glass curtain wall, let’s take a look together?
1. What is an exposed frame glass curtain wall
An exposed frame glass curtain wall is a wall system that uses metal frames (usually aluminum alloy) to “frame” pieces of glass, and then assembles them on the exterior wall of the building like building blocks. The metal frame is completely exposed outside and can be seen at a glance, so it is called “exposed frame”.
This is what an exposed frame glass curtain wall looks like
What is the difference between an exposed frame glass curtain wall and a hidden frame glass curtain wall?
Some glass curtain walls have metal frames hidden inside the glass. From the outside, it looks like a whole piece of glass directly attached to the wall. This is a “hidden frame”. The metal frame of the exposed frame is directly exposed, with a stronger sense of lines and a tough temperament of “skeleton”.
2. Why is the exposed frame glass curtain wall so popular in the architectural world?
1. High appearance, versatile and high-end
The metal lines of the exposed frame give the building facade a clear geometric division, and from a distance it looks like the building is wearing a “checkered shirt”. Whether it is a square office building or a streamlined art gallery, with a silver-gray, black or champagne-colored metal frame, it can instantly enhance the “high-end feeling”. For example, Beijing International Trade Phase III and Shanghai World Financial Center both rely on exposed frame curtain walls to support the aura of “urban elites”.
2. Strong and durable, specializing in all kinds of “disobedience”
– Wind and earthquake resistance: The metal frame is like a net that firmly fixes the glass. In the event of strong winds or earthquakes, the frame can disperse the pressure and prevent large-scale shattering of the glass.
– Waterproof and leakproof: The frame and glass are sealed with rubber strips, and there are drainage holes at the joints. When it rains, water will flow along the grooves of the frame and will not seep into the building.
– Durable: Aluminum alloy itself is not afraid of rust, and the surface will be oxidized (similar to “plating a protective film” on the metal), so it is not easy to deform or fade after 20 to 30 years of use.
3. Simple installation and convenient maintenance
Each piece of glass is installed independently, like Lego. If a piece of glass is broken, the workers will directly remove the corresponding frame and replace it without having to tear down the entire wall. For the property, this is simply worry-free and cost-saving.
4. Can play with “black technology”
Today’s open frame curtain wall is no longer “dumb and rough”, and there are many new tricks:
– Double-layer hollow glass: Inert gas is filled in the middle, warm in winter and cool in summer, and can also soundproof (the speakers of the square dance downstairs have become “dumb”).
– Low-E glass: Reflects ultraviolet rays and saves half of the air conditioning fee in summer.
– Smart dimming glass: Transparent when powered on, frosted when powered off, the privacy of the boss’s office is fixed in one second.
3. How did the building master “stick” it to the wall?
Although the curtain wall is just “hung” outside the building, there are so many technical details behind it that you can write a book. In short, there are four steps:
1. Build the skeleton: first put a “steel frame vest” on the building
Workers will first install the main keel (vertical metal column) and beams (horizontal metal strips) on the exterior wall of the building to form a huge “grid”. These keels should be bolted to the main structure of the building (such as concrete beams) to ensure that they will not be blown away when strong winds come.
Key details:
– Expansion joints should be left between the keels to prevent deformation caused by thermal expansion and contraction.
– Fireproof layer should be installed on each floor to prevent flames from jumping up along the curtain wall in case of fire.
2. Install the frame: “stuff” the glass into the metal frame
The factory will assemble the aluminum alloy frame and glass in advance, and directly clip them onto the keel after transporting them to the construction site. The frame and the keel are fixed with screws or buckles, and the position can be fine-tuned to ensure that all the glass is aligned (good news for people with obsessive-compulsive disorder).
Why use aluminum alloy?
– Light (one-third lighter than steel), reducing the burden on the building.
– Easy to process and can be made into various shapes (such as curved frames).
– Rust-proof, suitable for wind and rain all year round.
