attic condensation

hey, as the temp dropped in ny, i noticed that water was dripping down the interior of an exterior wall. i went to chech the attic, and found that all of the roofing nails coming through the roof had drops of water. it is not that the roof is leaking since it is on every nail. im guessing this is not normal.
1. how can i resolve this moisture problem in the attic...ventilation?
2. would this cause the moisture on the interior walls downstairs?
thanks
birch

 

A few years back, we had a major snow and then below zero temps for several days. Man-o-man you talk about leak probs! What was happening is the roofs were getting ice dams about 6 feet up from the gutters from the melt off and they finally worked their way into and under the shingles. then what warmth that was in the attic caused it to melt and wow...problems. I have a feeling this is what most you guys up there is seeing. Icicles hanging off the eves is a major tip off.

But IF the attics were well ventilated and insulated, no probs. If you are experiencing similar problems all I can say is TRY to minimize the damage and when the artic blast is over check your insulation and ventilation.

 

This time of the year, it is not unusual for homeowners to experience ice dams, condensation, frost and mold on roof trusses and sheathing, condensation near vents or plumbing stack, condensation near wiring or electric fixtures, and/or water draining from soffit vents.

Moisture and condensation in the attic can be caused by ice dams, gaps and cracks in ceiling, allowing warm air to escape to attic, uninsulated and unsealed attic hatch, missing chimney firestop, kitchen and bathroom exhaust fans vented into attic, unsealed electrical or plumbing fixtures, vents, etc., leaking roof, and leaky, uninsulated ducts in attic. Note: When warm, humid air makes contact with a cold surface, condensation tends to develop as on the outside of a glass containing an ice cold drink.

You can typically solve condensation problems in attic space by sealing all openings to attic to prevent house air leaking into the attic, sealing and insulating attic hatch, installing and sealing chimney firestop around chimney to reduce amount of air leaking into attic, exhausting all vents to the outside, sealing around light fixtures, repairing roof and flashings, and sealing and insulating ducts passing through attic.

In addition, you can reduce the humidity level inside your home. Pick up an inexpensive hygrometer and test the levels of humidity in the different rooms of your home. Humidity levels should be maintained between 30-50%. If less than 30%, a humidifier can add humidity. If more than 50%, a dehumidifier can reduce humidity. Most humidity in the home is generated in bathrooms and kitchens. Run exhaust vents for at least 30 minutes after cooking and bathing to assure excess humidity has been exhausted.

Unvented gas logs also add moisture to the air. A byproduct of combustion is water. The moisture may be beneficial in winter when the air in homes becomes dry. In tightly insulated homes, humidity problems typically can be quickly identified by the condensation on windows. Gas logs are a supplemental heat source and should never be used as the only heat source in a home. Too, they should be turned off before you leave home or go to bed.

 

Birch:
Some good replys here, and I will now address your original question. The answer is YES. The roofing nails are your cause.
On top of your roof they are cold, but since they stick through your roof the bottom of the nail is warm, and creats condensation.
The droplets run down your roof line to the exterior walls, and usually show up on the interior of it. A quick fix is to put a box fan in your attic to circulate the air, which will evaporate most of it.
You will be warming up in a few days and will notice that it stops.
This is very common in the upper plains where it gets as cold as you have everyday. Have a good day. Only 25 below here tonight.

 

Its all been said here I just wonder if you have any V/B there in the attic like does the insulation have paper on it to the room side or is there a poly under it? It was asked but no answer .Do you have vents up there in the attic? ED

 

thanks for all the help
to answer some questions, there is insulation in the floor joists of the attic w/ paper v/b facing down, and there is a vent along the peak. im going t o try to put o fan in for greater circulation until the freeze is over. Some people have said that it has to do with an ice dam, is this normal, or should i have someone look at my roof (it was just put on last summer)?
thanks again
birch

 

You have to get outside air in that attic. Can snow have the ridge vent sealed . They do sometimes. When they say ice dam its down over the over hang and water backs upand gets under the shingles there. you could ask the roofer if he did put ice shield under it there ED

 

i have the same problem .. only it started because added insulation to my attic... now i have condensation on my roof sheating. and now it is starting to freeze... but i noticed that in a area that i did not finish the insulation that the sheating was dry... after talking to a engineer.. he said i lowere the temp in the attic . and now it reaches the dew point of the temp... so either add more insualtion or add to heat to the space.. he suggested adding a string of lites... with 75 watt bulbs.. all the vents are clear ............ will let you know what happens