Attic Humidity Levels

The humidity in the basement measured 40 the first floor was 45 50 but the attic was 62.

Attic humidity levels.

During the winter months the recommended relative humidity inside a house is anywhere between 30 50 percent. When it exceeds that threshold by too much and for too long you could experience problems like mold growth. High humidity means greater chances for mold to grow. During the spring summer and fall relative humidity rh in a spray foamed attic often exceeds the comfort threshold of 60.

Winter air is by nature not humid so the problem must be condensation related. A hygrometer is a small gadget that measures the relative humidity level and temperature quickly and easily. You can check the humidity level by observing the windows and the objects in the attic. The short answer to this very involved question and the pages of temperature and humidity level data you sent is yes there is a risk that moisture from humid air in your attic will condense on.

If there is excessive moisture accumulation in your attic it will condense on cold areas mainly on the underside of your roof deck. According to the environmental protection agency epa indoor humidity levels should be kept below 60 percent relative humidity and ideally between 30 and 50 percent. The recommended humidity level for all rooms including the attic and crawl space in the winter is 30 to 40 percent in cold climates. If water is running down the window or objects seem wet to the touch then the humidity is far too high.

The moisture was rising with the warm air of the home as it escaped past the insulation and it was trapped in the attic because there was no roof ventilation. It s easy to measure the levels in your home by using a hygrometer. The normal indoor humidity range in winter should be 15 to. When it comes to humidity you would be best to have the levels below 50 to avoid mold growth and structural rot.