"Inside the glass" can mean moisture on the room-facing surface or mist trapped between the panes. This guide focuses on moisture within the sealed glass section of a double- or triple-glazed window.
Check where the mist appears
Look from a safe position. If water wipes away from the room-facing glass, it is on that surface. Mist that appears deeper inside the glazing needs a closer assessment. Do not lean outside or remove any part of the window to investigate it.
What mist between the panes can mean
The panes in a sealed glass unit are joined around their edges. Condensation between them can indicate a problem with that seal. A glazing professional can check whether this is what you are seeing and assess the condition of the surrounding window.
Opening a room vent changes the air in the room. It does not repair the sealed gap between the panes.
Record the affected windows
Take a photo of the whole window and a closer view of the mist. Label the room and note whether the appearance changes with the weather or time of day. Include any difficulty opening or closing the window.
Keep the original order and warranty information if you have it. Ask the original supplier or a qualified glazing professional about an assessment and the available options.
Decide after the assessment
The condition of the glass, frame and opening parts matters when deciding what work is appropriate. Ask for a written explanation of the problem and the proposed work before agreeing to it.
If you decide to consider complete window replacement, W4Y can prepare an initial estimate from photos and approximate measurements.
Questions
Will trickle vents clear mist between the panes?
They cannot repair a failed glass-unit seal. They serve the room's ventilation and are a separate part of the assessment.
Does one misted pane mean every window needs replacing?
Have the affected window assessed first. One problem does not establish the condition of all the other windows.
Can I claim under a warranty?
Check the original paperwork and contact the provider named in it. The cover and any conditions depend on that agreement.
If you are considering complete window replacement, send photos, approximate measurements and your postcode for an initial estimate. The final survey follows after you accept the estimate.
