Some methods for correcting moisture problems under the house include installing gutters to transport rainwater away from the foundation, fixing plumbing leaks and running a dehumidifier in the crawlspace. When installing a gutter system, ensure that the downspouts reach beyond the planting bed and toward the yard; otherwise, rainwater still may seep underneath the house.
Clogged gutters can also allow water to accumulate in the house's foundation and subsequently the crawlspace or basement. Unusual amounts of mold, mildew and dampness in a specific area may be indicative of a plumbing leak, which is usually fixable by installing a new pipe or a repair sleeve around the damaged or degraded segment. In cases of extreme moisture that lack easily identifiable sources, it may be necessary to install a dehumidifier underneath the house after first sealing the crawlspace or basement. This involves blocking outside vents and taping seams.
Utilizing passive ventilation is another effective method for countering moisture problems under the house. While exhaust fans and other forms of mechanical ventilation can be helpful, they also increase energy bills and experience eventual failure. Foundation vents and daylight windows are helpful sources of passive ventilation that only require clean surfaces to allow optimum air flow. When using passive ventilation, ensure that the vegetation and other obstructions do not interfere with the venting.