Do you think that the glass curtain walls of a building are a one-time thing? Wrong! Like cars, they also need “maintenance”! Many glass curtain walls leak, fog, and rust hardware after only ten years of use. It is not cheap to repair glass curtain walls, which makes the owners feel distressed! For glass curtain walls, as long as you do these things right, it is entirely possible to keep them stable for 30 years. Zhongdong Curtain Wall will tell you the secret:
1. Think long-term when building glass curtain walls (design & construction)
Don’t just pick thick curtain wall glass, the key is to look at the “combination”:
Ordinary single-layer glass? It’s cold in winter and hot in summer, and it’s easy to condense! Choose double-layer hollow Low-E glass: the middle of the two layers of glass is filled with inert gas and covered with heat-insulating film. It can’t be penetrated by sunlight in summer, and the heating can’t escape in winter. It is also UV-resistant, and the glass itself is not easy to age.
Although double-layer hollow Low-E glass is more expensive, it is worth it in the long run.
Aluminum alloy frame: Pay special attention to coastal cities!
Don’t be greedy and use “recycled aluminum”! The seaside is humid and salty, and it rots quickly. You must use high-grade rust-proof aluminum, and the thickness must be sufficient (at least 3mm). It is more expensive, but it can be used for more than ten years.
Drain holes are the lifeline! 90% of glass curtain wall leaks because of it!
Imagine that the curtain wall is like an umbrella, and it must have a “drainage trough”. When designing, at least 2 small drainage holes (>5mm) should be opened in each horizontal frame, and there must be a slope to ensure that rainwater flows away and never accumulates water! Keep a close eye during construction, and don’t let the workers be lazy and block the holes.
The screws connecting glass and metal must be made of truly rust-proof stainless steel. The cheap ones in roadside shops will rust and break in a few years, and it will be terrible if the glass falls off!
Don’t put the rubber gasket directly next to the glass glue. Over time, a chemical reaction will occur, causing the glue to crack and leak. Use a special isolation gasket.
Wind and shockproof: safety first!
In places with frequent typhoons, the wind pressure calculation must leave enough safety margin (at least 1.5 times the national wind pressure), don’t gamble on luck to save some money on materials. When installing the glass, special rubber blocks must be placed in the frame to prevent the glass from breaking when it hits the hard surface.
2. Points to note in glass curtain wall construction
The key to preventing leakage is to apply glue to the glass curtain wall! :
The glue seam width is at least 6mm (8mm in areas with frequent earthquakes), and the depth is half of the width. Too thin and too shallow is equivalent to applying it in vain!
Gluing depends on the weather: Don’t apply if the humidity is too high (>80%) or it is about to rain, and protect it from rain for at least 3 days after applying it.
Case: The glue of a shopping mall in China was too thin, and it leaked into a water curtain cave in just 3 years. The repair cost is dozens of times more than the money spent on the glue!
The glass of the glass curtain wall must never hit the metal frame directly! It must be separated by chloroprene rubber pads, one every 30 cm, to prevent the glass from being broken due to thermal expansion and contraction.
The metal frame of the curtain wall must be firmly connected to the lightning protection network in the building! Use professional instruments to measure the resistance, which must be less than 0.2 ohms. Otherwise, the curtain wall may become a lightning rod when struck by lightning!
3. Daily maintenance of glass curtain walls: spend little money to save big money
Inspect the glass curtain wall twice a year
Check the glue joints: take a flashlight to see if there are cracks or pinking? If the cracks have widened a lot (>10%), call a professional immediately.
Touch the hardware: shake the window handles and hinges with your hands to see if they are loose? If they are loose, tighten them (with an Allen wrench).
Clear the drainage holes: find a thin wire and poke the drainage holes one by one to ensure smooth flow. Pour a cup of water (500ml) and try it. If it can drain within 10 seconds, it is qualified.
Solution to emergencies
The glass curtain wall exploded by itself. Apply high-strength explosion-proof film indoors to temporarily fix it. New glass must be replaced within 48 hours! When changing, it is best to choose “super-stable glass” (homogeneous tempered glass), which has a very low chance of self-explosion.
Typhoon warning is coming: close all windows immediately! Check again whether the drainage holes are unblocked! Put in all the billboards and decorations hanging outside the curtain wall!
4. Don’t rush to remove the old curtain wall! It is more cost-effective to renovate the glass curtain wall
Case: A shopping mall in Shanghai, the curtain wall has been used for more than ten years:
Replace the single-layer glass with “double hollow laminated glass” (three layers of glass with two layers of glue), and the insulation, sound insulation and safety are upgraded!
Clean up the old glue that has aged and cracked thoroughly, and re-apply high-quality structural glue.
Cost comparison:
The lifetime money of the glass curtain wall = 10% is the installation fee + 70% is the maintenance and repair fee! Spend more time on the early design and construction, and keep up with the later maintenance, easily save 40% of the maintenance cost, and the building will be more valuable!
