The normal indoor humidity range in winter should be 15 to.
High humidity in attic.
To alleviate high humidity you need to have the best dehumidifier for an attic that can prevent the excess moisture from flowing in.
During the winter months the recommended relative humidity inside a house is anywhere between 30 50 percent.
If the attic is at 80 f and 80 humidity that s about a 21 torr vapor pressure of water.
Jason advani jason advani thought he was on the right track when he insulated the bottom of the roof deck in his walk up attic with closed cell spray foam.
That along with proper insulation should take care of the moisture problem.
Outside air moves into the attic leaves its moisture behind amd moves on.
Humidity settings are another issue that can make or break the performance of your heating and cooling systems and your attic ventilation.
Causes of high indoor relative humidity low heat load short equipment run time system oversizing.
That s way too high.
In contrast the humidity near the ridge in the attic gets very high.
High humidity means greater chances for mold to grow.
However you need to have a specific dehumidifier for the job.
This is exactly how water accumulates in your gas tank by the way the scientist next door.
Humidity inside a home should be maintained between 30 and 60 relative humidity.
High humidity in attic.
Proper ventilation will help maintaining a constant temperature in your attic.
If water is running down the window or objects seem wet to the touch then the humidity is far too high.
Jason advani has insulated his attic with spray polyurethane foam and while his heating bills have dropped high humidity remains a problem.
Sealing attic hatches duct work recessed lighting venting bath fans to exterior etc.
You can check the humidity level by observing the windows and the objects in the attic.
As planned the r 40 worth of insulation has drastically reduced his heating bill but now he faces another unexpected problem.
By scott gibson march 18 2019.
The dew point and rh stay below 70 f and 70 at their peak the peak of humidity not the peak height in the attic.
So compared to that hot humid attic the vapor pressure at the other side of the foam is a factor of six higher.
The dew point and rh get up close to 90 f and 90.
I like to shoot for 50 in humid climates when possible and by possible i mean financially feasible for the customer because anything is possible.
Attics can get hot and humid during the summer especially when the outside air leaks in.