My home is a single level ranch style. All new windows that are less than 4 yrs old. It has base board heating. During the cold season, when the heat is on, there is an extreme excess of condensation on the inside of the windows in most rooms. In one bedroom, where there is a large bay window and small sliding window, I frequently find pools of water at the base of the bay window. Even the ceiling in one side of that room occasionally has droplets of water in about an area of about 1 foot and shows speckles of mold. I clean using a bleach solution but it comes back every month. This is the worst room in the house.
I have checked the insulation in the attic and it is sparse. Even the walls adjacent to the exterior are cold to the touch in the winter. I have 3 to 3 hanging bags of "Damp Rid" in the room but the problem persists. I have used a Dehumidifier in the past but it really drives up my electric bill.
My question is why is there so much condensation happening? What can be done to prevent or reduce it? Thank you for the feedback.
Best Answer
You get condensation because the windows (and evidently part of the ceiling, unless that's just a roof leak) are the most poorly insulated part of the building, so they cool below the dewpoint of the interior air.
Bay windows are particularly bad as they are a fairly large expanse of window stuck out into the cold, and not infrequently the non-window parts of the bay are not well-detailed from an insulation point of view. They also have a lot of joints making potential cracks to leak cold air.
Active ventilation can help remove some of the interior moisture (from whatever sources), but since your investigation has shown poor insulation, solving poor insulation is probably a good idea as part of the overall fix.
For a quick, inexpensive approach on the windows, consider using "window shrink film kits" for the winter. They effectively make an interior "storm window" and both reduce air leaks and radiative heat loss. If done carefully they don't look bad.