This winter in the attic I noticed ice on the roofing nails. Obviously warm moist air condensed and then froze on the cold nails. When the weather broke and warmed up a bit, I was back up in the attic and noticed black mold on certain areas of the lower attic ceiling going toward the eaves.
Some interesting facts:
- I have been in the house two years and did not notice this happening last year.
- This is only occurring on one side of the attic ceiling, the other side is completely fine (no rusted nails poking through, no mold)
- I recently put down some more plywood so I can have more area for storage, and before I did that I added some more insulation to the attic floor (rolls). I wonder if that has anything to do with it?
- It was also a colder drier winter this year so we had humidifiers in use more, so that may also have something to do with it.
I am just curious why it is happening this year and not last year, and why on only one side of attic ceiling (roof).
- For ventilation of the attic we have only two gable vents (one on each side of the house), about 1.5ft x 2ft rectangle each. These do not have any fans.
- There are no soffit vents or ridge or roof vents; just the 2 gable vents.
- Looking at the lower part of where the attic roof slopes down and meets the wall I notice there is a board that blocks the attic area from the soffit area/eave. So if I was to put in soffit vents from outside, I believe I would have to also drill holes from inside attic through this board so the outside air could actually pass into attic and not be trapped in this blocked off area.
- The attic space is about 600sq ft.
- The only insulation is in the attic floor and on there walls, there is no insulation on the attic ceiling.
- Bathroom fans are vented to outside the home (not into the attic or soffit)
- I live in Massachusetts where winters get cold and summers are hot and humid.
- What should I do?
- Why was the gable venting system in place good enough last year but not this year?
- Why only one side of attic affected?
I recently beefed up the insulation and seal on the pull-down attic entrance as this could be an area where warm moist air was entering into the attic (the entrance is on same side as the attic problem area). Will that fix problem, or do you recommend installing more ventillation anyways?
Will a fan on the gable vents do the trick, or do I need to install soffit vents anyway?
Will soffits with the gables work, or will ridge or roof venting also be required?