Water spot in ceiling above bay windows

Susan M
by Susan M
I have tow bay windows, there are water spots in the ceiling above each. The roof and attic have been examined no sings of leakage or water spots. Any idea on what the cause is and how to fix it
  10 answers
  • Jackie Johnson Jackie Johnson on Aug 28, 2014
    Without pictures or a drawing, my best guess is that you have a problem with the flashing, usually a metal barrier that deflects rain run-off from the vertical wall above the bay to the roof of the bay itself. You would also see flashing where your fireplace chimney joins the roof of the house. Unfortunately, I don't know a fix for this that does not involve taking the ceiling of the bay out completely with the hope that you can fix the flashing problem from there, but either way you've got to take the sheetrock out of the bay ceiling. Unchecked moisture in an enclosed space like that is an invitation for toxic black mold.
  • Hannah V Hannah V on Aug 28, 2014
    Hey Susan! You should upload a photo of your water spots. That will give Hometalkers and myself a better idea of how to help you. Adding a photo's easy- see screen shot attached for editing! :)
  • Linda Thomas Linda Thomas on Aug 29, 2014
    When it is really hot outside your ceilings sweat especially at windows. Take a spray bottle and put colrox in it and sray the water spot and it will disappear.
  • Susan N Ricky Lemieux Susan N Ricky Lemieux on Aug 29, 2014
    We live in texas along the gulf coast and had a problrm with water dripping on us in our bedroom at night. Thought for sure it was roof leaking. Had roof and attic inspected and no leak. Finally figured out it was the AC we had recently purchased. Called manufactuer and she said that yes it can happen if you get an AC that is too big for the space you are trying to cool and told us not to run it on high and bump the trmperature up a bit especially when it rains or humidity is high, which is most of the time in thr summer where we live. Gets so hot and humid hear husband and i likr to sleep with the bedroon very cool at night
  • Susan N Ricky Lemieux Susan N Ricky Lemieux on Aug 29, 2014
    Also a de humidifier might help
  • Susan H Dittman Susan H Dittman on Aug 29, 2014
    @Susan M Any water in your house indicates a "Water Damaged Building" (WDB) and you probably have toxic mold. Clorox/bleach only give the appearance of killing mold. It does not kill the spores or the "tentacles". Fix the problem or it could damage your health. Pay the money for a good solution or pay later mysterious health problems and worse damage to your house. I've ignored water damage and paid the price.
  • Kelly S Kelly S on Aug 29, 2014
    we had to replace our roof, drywall and insulation because the roofers didn't put flashing in the gutters where the bay window roof meat the angled roof and then didn't weave the shingles correctly. This caused pine needles to catch and build little dams on the roof which allowed water to enter the walls. We found this out about 7 years into the new construction house. We found the problem when it started to rain, literally inside the house at the window. $8K for a new roof and $1K to fix all the inside damage including repair the subfloor since it had been leaking for a couple of years, we just didn't know it because there was indication of dampness inside the house. FIX it now or like @Susan H Dittman says pay for it later. Get a qualified inspector/engineer to check it out.
  • Leslie Leslie on Aug 30, 2014
    Is there a vent opening on the outside wall above the window from a bath or stove hood? If it is damaged water may enter in a storm.
  • Susan H Dittman Susan H Dittman on Aug 30, 2014
    Kelly S so sorry to hear of your expensive fix, but glad you got it done right this time (sounds like). I also didn't know the word "flashing" but do now and so will my children! The gutters on the backside of our house were not wide enough and poorly engineered (water didn't run off properly) and we had inadequate flashing. Our fix was about 30K. We thought we had hired a good builder--ask questions, get the work inspected, pay a little extra to make sure your house is protected from WATER. Insurance will not cover these slow leaks or mold.
  • Karen swift Karen swift on May 08, 2016
    got to be gutters or your flash banding as water always finds lowest point