Causes of Leaking Windows With Condensation

Location of Leak

• The location of your leak can tell you a lot about the source of the water. If you are seeing water pooling underneath the window on the sill, you are likely looking at a decaying or decayed seal across the bottom of your window. Spread baby powder on the sill and on both sides and the top of your window to help track the source of the water. Water trickling down will leave telltale lines in the powder which will help you trace it back to its source.

Leaking Roof

• Examine the area above the window for any signs of water damage. Occasionally a window leak can actually be a leaking wall due to a damaged roof that is simply dribbling water down onto the window. Press on the drywall or plaster above the window, and look closely for stains or bubbling indicative of water damage.

Damage to the Window Itself

• Condensation located on the inside of the window -- meaning you can wipe it from the glass while standing inside -- is not a particularly indicative symptom. Water trapped in between the panes of glass in a double pane window -- meaning water that cannot be touched either from outside or inside of the house -- means your window itself has had its seal broken. The wood may have decayed or there may have been damage done from the outside, but in either case the window must be replaced.

Improperly Hung Window

• A window that has been improperly hung will not close evenly at either the top or the bottom, which will leave a gap and cause water to slip in above or below the window. If the leaking window is a new installation, this is the most likely culprit for a leak. In an older house, the settling of the house can actually cause windows to cease to fit properly. No remedy exists other than window replacement.