Hi there. Perhaps someone has some idea of what my problem is and/or how to trouble shoot it. Contrary to what is typical, when I turn my furnace on each winter immediately all of the windows in my home (twice as badly upstairs) begin to sweat or collect lots of moisture and water on them. This problem is rotting my wood windows. I wipe them down every day just to find more water the next day. It is frustrating and damaging to my house. We must have too much moisture in the air. Usually a furnace dries a house out, hence the need for a humidifier (which we have but certainly don't use). This is an 11 year old house with original anderson windows. Am I destined to use damp rid and run the dehumidifier all winter? And could this be a sign of a more serious problem? Is the house not 'breathing' or venting properly? Thanks suz

Has it always been this way as far as you know? It sounds like a combination of a well sealed up house and excess moisture. Do you have unusual sources of moisture, teenagers addicted to long hot showers, generous amounts of house plants, a sauna or hot tub, fish tanks, or anything else that might put moisture in the air? If not, I would look at moisture from the ground. Basement, crawl space, or slab, moisture can work its way into the house through the floor. A crawl space my be the easiest to fix by putting down plastic sheeting and sealing it well. Basements and slabs are harder to fix if not done right in the first place. Even there, proper grading may help by directing surface water away from the house. The ground level should be at least 8'' below the siding, and slope away from the house all around. If the ground slopes toward the house on the upper side, you may need to cut a swale to direct the water around to the lower side. Check any foundation drains you have and make sure they are flowing. Do you have a sump pump, and does it run frequently? If you have A/C, does it produce volumes of condensate in the summer time? Another thing to check, which could be a threat to your life is a furnace flue leak. Could be getting both moisture and carbon monoxide from the furnace.

You may want immediate relief by leaving a few windows open a crack. I don't think that is a good long term alternative with heating prices going up. They do make air to air heat exchangers. They bring in dry outside air while saving some of the heat.

Post back with details. I doubt there is a single, simple answer to this.

We have this problem as well. Our friend who works with corporate AC suggested that we run the fan on our system constantly. We did that this winter, and noticed a huge change in the dampness in the house. We also ran all of the ceiling fans so that they circulated air upward instead of blowing down. Because our home is so airtight, these changes only had minor impacts on our energy bills (an increase of about $5 a month). I also have a small electronic dehumidifier that I keep underneath my dresser. I dis-charge it every couple of days in the bathroom with the door closed and the vent running to get the moisture out of the house. I had to throw away several shirts because of the moisture that gathered beneath my dresser. I even bought a new dresser. Hopefully these changes will save my wardrobe! (and my windowsills)

PS Stop Nine spray will kill and clean up the mold on your windowsills.