Moisture Locations: In most residential and commercial structures, common locations of excessive moisture are basements, crawlspaces, attics, exterior walls, ceilings and wood floors. Moisture from wet soil in crawl spaces can add over 47 quarts of humidity to the daily 20 quarts produced by a household of 4. Common sources of excessive moisture are inadequate drainage and ventilation, moisture intrusion through roofs and exterior siding, interior plumbing, improperly vented dryers, high efficiency heaters and AC’s. Today’s homes are well insulated and modern heaters will not dry out interiors and walls like older stoves and fireplaces did in the past. Condensation and moisture intrusion will then remain for longer periods before it can evaporate and allow wood members to dry again.
Interior Moistures Sources: Undetected plumbing leaks from supply and drain lines can easily flood basements and crawlspaces for long times without owner or occupants knowledge. Sump and sewer pumps can also stop working during rainy weather when needed most. In bathrooms, leaks from faulty shower pans, loose toilet stools, as well as moisture seeping through caulking and grout cracks, shower or tub enclosures, window ledges or beneath vanities can cause hidden damage to walls and adjacent flooring. In the laundry room improperly vented dyers, leaking sinks and failing washing machines can also wreak havoc. In the kitchen leaks from dishwashers, sinks, water filtration systems & icemakers can also cause damage in hidden areas.
Exterior moisture sources: Mother Nature is powerful and persistent, and moisture often comes from hillside or lateral seepage, not to mention from the sky above. Inadequate or clogged underground drainage, leaking exterior plumbing and improperly set landscaping irrigation are also common sources of moisture intrusion. Among the many culprits of moisture intrusion are cracks and voids to exterior wood and stucco walls, inadequate or aging exterior siding, improper flashing around windows, doors, exterior trims and protrusions. Additionally, leaking or incorrectly installed windows, doors and deck attachments can also contribute to moisture intrusion. Aging or improperly installed roof, flashing, gutters & downspouts will also cause leaks and moisture. Finally, aging paint and vegetation growing against the structure can raise humidity in some areas.
Symptoms and Causes: Pooling and stagnant water and excessive humidity in basements and crawl spaces also promote rust and deterioration of foundation reinforcement bars, seismic anchors, heating ducts and plenums. Moisture will also deteriorate copper and galvanized plumbing pipes and cast iron drain lines, sometimes leading to hazardous leaks. Vegetation such as vines and tree roots growing in crawlspaces, under slabs and in wall voids will also do better in a moist environment.
Finally moisture can accumulate in the form of standing water and sludge in crawl spaces leading to excessive evaporation, damp and dank odors and warping of wood floors. Some insects such as termites, beetles, gnats, flies and many others favor humidity and so do some rodents (rats, skunks, raccoons, possums, etc.).
Risks and Hazards: Excessive moisture in your home can also lead to health issues. In addition to smell and discomfort, allergies and some diseases can be more prominent in a humid environment. Fungal activity such as wood decay damage, or dry rot, mushrooms, mildew and mold may set into interior as well as hidden or inaccessible areas. Mildew and mold will more easily set into enclosed areas such as cabinets, closets and wall voids, but it will also develop behind beds, furniture and beneath carpeting. Of all interior areas, bathrooms, kitchens and northern sides of homes are most likely to experience fungal activity. With time and excessive moisture, some mildew and mold can carry airborne spores that may cause health hazards and specialists in these matters should be consulted.
Detection: Owners maintaining their property should keep a watchful eye and report to the appropriate professionals any suspicious water and rust stains, high humidity and damp smell, pest infestation as well as settlement cracks and damaged or deformed floors. Using trained and experienced licensed professionals is the best way to tackle problems and obtain expert advice. Aside from visual observations and probing damaged areas, some professionals specialize in the use of high-tech detection tools such as moisture meters, infrared cameras, leak detectors, borescopes, pipeline and cable cameras). Sometimes intrusive investigation (test holes and opening inaccessible areas) is necessary for additional inspection. Finally, it is important to observe the surrounding environment and location of the building that may subject the structure to outside conditions.
Prevention: Adequate drainage within and around the structure is critical. This includes proper grading, well-engineered French drains and drain lines channeling rainwater from gutters and downspouts away from the structure. Installing vapor barriers under slabs and on substructure soil in crawl spaces will also create a drier environment. However, this will only work if drainage is adequate and functional. Periodically serviced and operational sump pumps are critical in areas where water accumulates below grade, such as in deep crawl spaces, basements and on low level grounds. Adequate insulation properly installed (vapor barrier against the living area) with proper ventilation will also help deter excessive moisture in crawlspaces and bathrooms. Aerating the interior and adequate ventilation is also critical in tight and enclosed areas such as closets and storage rooms. Properly flashed windows, doors and roofs are crucial as well as caulked and painted areas are also critical. Finally, all parts and equipment found in a home need periodic servicing and inspection.
Conclusion: If it doesn’t look, feel or smell right, chances are that it isn’t! During the course of property maintenance, observe the grounds and structure. Keep your home dry and aerate interiors as often as possible.
Call Marin Termite to have a licensed professional inspect your home when you suspect something is wrong. It is also economically wise to have periodic inspections. Remember: An ounce of prevention is worth a pound of correction. Maintain your property in good working condition, replace aging and failing components and have all critical equipment routinely checked and serviced by licensed or certified professionals.