The appearance of bubbles in the middle of laminated glass is a relatively common but indeed troublesome problem. The feasibility of the treatment method entirely depends on the size, quantity, appearance time of the bubbles, as well as the type and installation location of the glass.
The main cause of bubble formation
Understanding the cause helps to determine the nature of the problem:
Production process issues: This is the main reason. During the high-temperature and high-pressure interlayer process, if the air is not completely discharged, the moisture content of the PVB or SGP film is inappropriate, or the process parameters do not meet the standards, bubbles will remain.
After installation, when exposed to heat or pressure changes: When glass is exposed to direct sunlight, especially when the edges of the glass are tightly fixed by window frames or sealants, the air in the middle expands due to heat and cannot escape, forming "hot air bubbles".
Poor adhesion between film and glass: Local delamination can lead to the gradual appearance and expansion of bubbles.
Edge seal failure: For insulating glass, if the outer seal fails, moisture entering the insulating layer may also cause problems at the edges of the laminated glass.
Judge and handle based on the bubble condition
Situation One: The brand-new, custom-made glass that has just been installed shows obvious bubbles
Solution: Contact the supplier or manufacturer immediately and request a free replacement.
According to national standards (such as GB 15763.3-2009 "Safety Glass for Buildings - Part 3: Laminated Glass"), there are clear regulations on the allowable defects of laminated glass. Generally, bubbles with a diameter greater than 2mm, dense needle-like bubbles, or bubbles that appear in key visual areas are all considered substandard products.
Your rights: This is a product quality issue. You have every right to request a return or exchange. Do not accept the "repair" solution, as laminated glass cannot be perfectly repaired on site.
Situation Two: New bubbles (hot air bubbles or later bubbles) that appear after being used for a period of time
Handling method: Decide whether to replace after assessment.
If the bubbles are small and stable: It might just affect the appearance. If it is not within the main line of sight, you can temporarily choose to ignore it, but you need to pay attention to whether the bubble has a tendency to expand.
If the bubbles continue to expand or increase: This indicates that the bonding between the film and the glass is failing, and the overall safety of the glass (impact resistance, integrity) will decline. It is strongly recommended to arrange for replacement as soon as possible, especially for parts that require safety protection such as guardrails, skylights and doors and Windows.
Situation Three: Very tiny and sporadic bubbles
Sometimes, there may be tiny bubbles the size of a needle tip at the edge of the glass or in non-central areas.
Judgment: According to national standards, extremely small and sparse bubbles may fall within the allowable defect range.
Handling: If it is very inconspicuous and does not affect the overall usage and aesthetics, you can negotiate a certain economic compensation with the merchant instead of replacing the entire piece of glass. However, if you have high requirements for quality, you can still request a replacement.
