Detailed explanation of the construction steps of glass curtain wall

s a common exterior wall decoration in modern buildings, glass curtain wall is not only beautiful and atmospheric, but also can improve the lighting and energy-saving effect of the building. But its construction process is not simple and requires multiple rigorous steps. Zhongdong Curtain Wall will talk to you about the construction process of glass curtain wall today.

1. Preparation before construction: Laying a good foundation is the key

1. Design drawings and on-site inspection

Before construction, the designer will deepen the design according to the architectural drawings to clarify the shape, size and material of the curtain wall. At the same time, the construction team needs to measure on site to check whether the wall is flat and whether the position of the embedded parts is correct. If the wall surface error is large, it may be necessary to adjust the design plan or make local repairs.

2. Material procurement and acceptance

The main materials of glass curtain wall include glass, aluminum alloy frame, sealant, etc.

Glass: usually hollow tempered glass (with air layer in the middle) or laminated glass (with film in the middle) is used, which can be both heat-insulating and sound-insulating, and safe and explosion-proof. During acceptance, check whether there are scratches and bubbles on the glass surface.

Aluminum alloy frame: Check the thickness and strength of the profile, as well as whether the surface coating is uniform, to prevent rust in the later stage.

Sealant: Choose silicone glue with good weather resistance to avoid cracking and leakage after a period of use.

3. Tools and personnel preparation
Commonly used tools include electric drills, cutting machines, hoisting machines, suction cups (used to carry glass), levels, etc. Construction personnel need to undergo professional training, especially when working at high altitudes, they must be certified to ensure safety.

2. Install embedded parts: “root” the curtain wall

1. Positioning and laying out
According to the design drawings, use a total station or laser level to mark the installation position of the embedded parts on the wall. This step is like “drawing a grid” and must be very accurate, otherwise the subsequent frame will be skewed.

2. Install embedded plates
The embedded parts are the “anchor points” connecting the curtain wall and the main body of the building, usually a steel plate with bolts. During construction, it is necessary to drill holes in the concrete wall and fix the embedded plates with chemical anchors or expansion bolts. After completion, check whether it is firm and the position deviation should not exceed 5 mm.

3. Lightning protection and grounding treatment
The curtain wall of high-rise buildings needs to be connected to the lightning protection system. Weld copper strips or flat irons near the embedded parts and connect them to the building’s lightning protection network to prevent lightning strikes from damaging the curtain wall.

3. Build the keel frame: the “skeleton” of the curtain wall

1. Install the columns
The columns are vertical support structures, usually made of aluminum alloy profiles. During installation, they are fixed layer by layer from bottom to top, and the spacing of each column is determined according to the glass size (generally 1~1.5 meters). The columns are connected to the embedded parts through angle codes. After tightening with bolts, the verticality needs to be corrected with a level, and the allowable deviation is no more than 3 mm.

2. Install the beams
The beams are horizontal supports that form a grid structure with the columns. During installation, pay attention to the drainage slope of the beams (usually tilted inward by about 5%) to avoid rainwater accumulation. Rubber gaskets need to be installed at the joints between the beams and the columns to reduce the impact of thermal expansion and contraction.

3. Check the overall frame
After the frame is installed, check whether it is horizontal and vertical, and whether the joints are tight. You can use the wire drawing method or laser instrument to detect and adjust in time if you find any problems.

IV. Install glass: Be careful and gentle, and accurately align

1. Handling and protection
Glass is fragile. When handling, you must use a special suction cup to avoid direct contact with your hands. Large glass also needs to be used with a hoisting machine, and a protective pad is set on the ground to prevent bumps.

2. Fix the glass panels
Exposed frame curtain wall: The glass is embedded in the groove of the aluminum alloy frame, filled with rubber strips around, and finally buckled with a pressure plate.
Hidden frame curtain wall: The back of the glass is directly glued to the frame with structural glue, and it needs to be fixed with a temporary clamp before the glue dries.
Point curtain wall: The four corners of the glass are fixed by stainless steel claws, which has a more transparent visual effect and is often used in shopping malls and exhibition halls.

3. Adjust the gap and flatness
After the glass is installed, the gap between adjacent panels should be uniform (usually 6~12 mm), and the surface height difference should not exceed 1.5 mm. If the gap is too large or uneven, you may need to readjust the frame or replace the glass.

V. Glue sealing: the last line of defense for waterproofing

1. Clean the joints
Use a brush and vacuum cleaner to remove dust and oil from the glass gaps to ensure that the sealant can be firmly bonded.

2. Fill the foam strip
Insert a foam stick at the bottom of the gap to control the depth of the glue (usually 1/2 of the gap width) to avoid wasting the glue.

3. Apply sealant
Use a glue gun to evenly inject silicone weather-resistant glue. The glue surface should be smooth and full, and fit tightly with the glass and frame. After applying the glue, use your fingers or a scraper to trim the glue seam to make it a concave arc to enhance waterproofness.

VI. Cleaning and acceptance: Make the curtain wall “bright”

1. Clean the surface
Tear off the glass protective film, wipe the surface with glass cleaner, and remove glue marks and stains.

2. Performance test
Water spray test: Use a water pipe to simulate heavy rain and check for leakage.

Air tightness test: Use a fan to pressurize and test whether the air leakage of the curtain wall meets the standard.

Glass strength sampling: Randomly select several pieces of glass and use professional equipment to test their wind pressure resistance.

3. Submit completion information
Including material certificates, hidden project acceptance records, test reports, etc., to facilitate later maintenance.

VII. Construction precautions

1. Safety first: Safety belts must be worn for high-altitude operations, and warning lines are set in the hoisting area.

2. Weather influence: Suspend outdoor operations on rainy or windy days (over level 4) to prevent the colloid from being washed away by rain before it dries.

3. Detail processing: Waterproof strips need to be installed at corners and joints to prevent rainwater from seeping into the wall.

Glass curtain wall construction is like “building blocks”, and every step must be precise. From preliminary preparation to final acceptance, it tests both technology and patience. With the development of technology, many projects have now adopted new methods such as BIM modeling and robot installation, but the core construction process still cannot be separated from solid basic work and strict quality inspection. Only by doing every link well can the glass curtain wall be both beautiful and safe, and become the finishing touch of the building.