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Condensation Removal
Window de-fogging

Window de-misting

The Process

Why windows fail

The majority of failed sealed units are found on the sunny side of the property.

·         Temperature

·         Pressure

·         Time

When strong sunlight hits a window, the increase in temperature makes the air between the panes of glass expand, increasing pressure on the glass and on the seals.

At night or on a cold cloudy day, the temperature drops and so does the pressure between the panes of glass, causing a suction effect.


This gradual flexing and pressure this cycle causes may eventually break the seal around the panes of glass.  When this seal is breached, moisture carried in the outside air is drawn into the sealed unit which causes condensation, or fog between the sheets of glass. In most cases the a seal break will take years to occur , if ever.

In the past when it did occur, a complete replacement unit was the only viable solution.  Although sealed units are made with water absorbant desiccant within the bar that separates the sheets of glass, when the seal fails this eventually becomes saturated. This allows water droplets to form on the glass and “misting” begins.

 In the early stages of visible failure, a mist may appear and disappear on warm days. But as more and more moisture is drawn into the sealed unit the fog becomes permanent, eventually staining the glass on the inside. Once this staining occurs the only option may be to replace the unit, which may be expensive.

But if caught early, an inexpensive option exists!

How we cure a window

The secret to the process involves the application of a patented “super-hydrophilic” nanopolymer coating to the internal glass surfaces of the insulated glass unit (IGU). When dry it prevents the moisture in the air condensing on the glass. Similar coatings are used on mirrors in bathrooms to prevent the mirror fogging up whilst you are taking a shower or bath.


We then install special vents into the unit to prevent water droplets or dust entering the IGU. In high humidity areas we install 'defogger' valves as well.


The unit will then need time for the hydrophilic coating to dry and the trapped moisture to evaporate, some units clear within a few days some can take up to 12 weeks to clear dependant the moisture level and length of time the unit seal had been broken.


Futuremost Service guarantees all of its work carried out on sealed units for 20 Years.  All our operatives are CRB checked for your peace of mind. Our guarantee is under-written by an insurance company for total peace of mind. Units that were serviced using the CCWW process in 1989 are still free from condensation today!

De-fogging service

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