Will the fog in the window glass interlayer disapp
Will the fog in the window glass interlayer disappear on its own
1、 Possible self disappearance (temporary condensation)
Short term temperature difference causes
When the temperature difference between indoor and outdoor is greater than 15 ℃ and the air humidity is greater than 70%, the surface of low-temperature glass will condense water vapor to form temporary mist. If the fog appears as a uniform thin mist, does not spread in area, and completely dissipates with temperature rise (such as at noon or after opening windows for ventilation), it belongs to physical condensation phenomenon and does not require special treatment.
Features: Mist can appear and disappear periodically, with no colloidal cracking or dust intrusion at the edges.
- Transition period for newly installed windows
Newly installed windows may experience brief fogging in the early stages due to moisture content in the material or incomplete curing of the sealant, which usually disappears with the evaporation of moisture after 1-2 months of use.
Suggested solution: Turn on the air conditioner for dehumidification (humidity control at 60% -64%) or briefly open the window to balance the temperature difference and accelerate dissipation.
The situation where it cannot disappear on its own (structural failure)
- Aging of sealing system
Cracking of sealant (butyl rubber powder cracking, silicone adhesive peeling) or deformation of hollow aluminum strips can cause continuous infiltration of external water vapor, gradually expanding the fog area, accumulating dust or water droplets at the edges, and such fog cannot be eliminated on its own.
- Desiccant saturation failure
The molecular sieve in the interlayer has a moisture absorption life of about 5-8 years. After saturation, it loses its moisture absorption ability, and fog will repeatedly appear and last longer.
- Process defects
The septum strip is tightly attached to the edge of the glass, without leaving a 2mm gap, or the drainage hole is blocked, causing water retention and continuous fogging.
Signs that require intervention for fault types
Cracking of sealant, visible colloid cracking or dust accumulation at the edge of mist
Desiccant failure and repeated generation of mist, exacerbated by rainy days
Incorrect installation of the partition strip, accompanied by fog and water accumulation in the window frame
Risk Warning: If the seal fails for more than 6 months without treatment, it may corrode the aluminum frame or cause stress cracks in the glass.
3、 Solution Selection Guide
- Mist that can dissipate on its own
Observation period: The temperature difference should completely dissipate within 72 hours after it decreases.
Auxiliary measures: Place activated carbon packs near the window to absorb moisture, or spray an anti fog coating (detergent 1:6 dilution) to temporarily suppress it.
- Mist that requires professional maintenance
(1) Partial repair
Remove aging sealant → re inject butyl rubber+silicone rubber double-layer seal (environmental humidity<50%).
Drill holes to replace molecular sieves or fill with argon gas (leakage rate<1%/year needs to be tested).
(2) Overall replacement
If the following situations occur, it is recommended to replace the entire glass unit:
There are oily stains in the mist (indicating complete seal failure)
White alkali marks appear on the inside of glass B (due to molecular sieve dissolution corrosion)
C adopts a warm edge 4SG system+Low-E coating (K value ≤ 1.0 W/m ² K) to enhance durability.
Ultimate judgment criterion: If fog appears continuously for more than 3 times under the same temperature and humidity conditions, it can be determined as structural failure and immediate intervention is required.
Will fog in the window glass interlayer affect the insulation effect?
Direct impact: significant decrease in insulation performance
The occurrence of fog in the interlayer of window glass can seriously weaken the insulation effect, specifically manifested as:
- Deterioration of thermal conductivity
Mist replaces the dry air inside the interlayer with water vapor, and the thermal conductivity of water (0.6 W/m · K) far exceeds that of dry air (0.026 W/m · K), resulting in a 23 fold increase in heat transfer efficiency. Actual measurements have shown that after fogging, the K value (heat transfer coefficient) of the glass increases by 30% -50%, and the rate of room temperature loss in winter accelerates by 40%.
- Inert gas failure
When the leakage rate of inert gases such as argon filled with insulating glass exceeds 1% per year, the insulation performance deteriorates by 35%, and fog is the direct evidence of gas leakage.
- Damage to coating function
The adhesion of water vapor will oxidize the LOW-E coating, reducing its infrared reflectivity by more than 40% and further reducing its thermal radiation blocking ability.
Associated performance degradation
The specific manifestation of data changes in the dimension of influence
Sound insulation performance: Water vapor filling reduces sound wave transmission loss by 5-10dB and increases traffic noise penetration by 2.3 times
Transmittance: Mist droplet scattering reduces visible light transmittance by ≥ 60%. Indoor lighting requires supplementary lighting of 40%
Structural safety: Water accumulation, rusting of aluminum partitions, risk of glass stress cracking increased by 300%, and the wind pressure resistance of the frame decreased by 25%
Repair priority judgment
A [Mist state] -->B {Does it contain oil stains/dust? }
B -->| Yes | C [Seal completely failed → Replace immediately]
B -->| No | D [Check frequency of occurrence]
D -->E [3 consecutive cloudy days] -->F [desiccant failure → drilling repair]
D -->G [Only appears in winter] -->H [Enhanced dehumidification+temporary sealing]
Critical standard: When the interlayer fog causes a 50% reduction in indoor and outdoor temperature difference perception (if the original 15 ℃ temperature difference isolation is now only 7 ℃), structural maintenance must be carried out.
Long term solutions
- Material upgrade plan
Warm edge spacing system: replace aluminum spacing with stainless steel composite tape, reducing edge heat conduction by 70%
Triple sealing structure: butyl rubber (inner layer)+silicone rubber (middle layer)+TPE elastic rubber (outer layer)
Self diagnostic glass: implanted with humidity sensing chip, automatic warning before saturation
- Emergency remedial measures
Argon refilling: professional equipment for replacing interlayer gas (leakage rate must be less than 0.5%/year)
Molecular sieve regeneration: Bake at 150 ℃ for 4 hours to restore 80% moisture absorption capacity (limited to 3A level)
Maintenance reminder: Use a humidity detector to measure the air humidity around the window frame before winter each year. If it exceeds 65%, start the dehumidification equipment to reduce the probability of fogging by 75%.