Any way to clean between the glass on patio doors?

expert EXPERT April 26, 2007

There are two different types of the double glazed door and window systems. On one system, the interior pane of glass is removable and is held in place by clips. The space between this interior pane of glass and the exterior pane of glass is ventilated. With the interior pane of glass removed, the inside of the exterior pane, and the inside of the interior pane can be cleaned. The more common system has the space between the inner and outer panes sealed. Conventional windows have air in the space between the glazing layers. Higher efficiency windows use heavy gases, such as argon, krypton, carbon dioxide or Freon , for example, to improve performance. These gases have lower thermal conductance than air. The downside of sealed windows is that eventually, they loose their seal, and moisture gets between the panes.

Lost seals are not particularly serious from an energy efficiency standpoint. The window will still perform reasonably well. However, visibility is often reduced, and the glass may look cloudy, even if there's no condensation present at the moment. Once the seal is gone, condensation will appear and disappear between the panes. This, however, leaves the interior surfaces of the glazing dirty, and the cloudy appearance develops. Unfortunately, the only fix is replacement.