The level of moisture in the home is
crucial to achieving a healthy home environment. Too little moisture in
the home can cause dryness of the nose and respiratory systems, while
too much moisture in the home contributes to numerous health impacts,
health hazards, and structural home damage. Asthma,
allergies, and other respiratory illness are the main health
impacts to children and other residents of homes with excessive moisture.
Excessive moisture also causes or contributes to other hazards to human
health such as mold,
mites, and peeling lead
Several common signs that conditions of excessive moisture
exist in the home environment include:
- Rusting metal
- Condensation on piping and/or windows
- Rotting wood
- Mold growth
- Peeling paint, wallpaper, or other blistering materials
- Deterioration of other structural items
- Visible water leaks and/or stains
- Discoloration of various surfaces
- Musty odors
- Standing water
These signs may be clearly visible or they may be hidden in places such
as behind walls, under furniture and carpets, and in crawlspaces or attics.
In assessing moisture problems in the home environment, it is important
to know such potential hiding places and visually inspect all areas that
are reasonably accessible. A low-cost moisture meter can also be used
to test for moisture in inaccessible places.
Moisture problems inside the home can originate from problems both indoors
and out. In general, preventing and eliminating moisture control problems
involves removing, diverting, blocking, or otherwise controlling the source
of moisture while also providing adequate ventilation.
Some specific tips to prevent and eliminate excessive moisture in the
- Regularly clean and maintain gutters, and ensure
that they drain away from the foundation of the building structure.
- Install and run exhaust fans in the bathroom and kitchen or open
windows for adequate ventilation.
- Vent all fans and appliances to the outside of the home.
- Do not arrange or store items (furniture, storage boxes, etc.) so
that they touch the interior side of exterior walls.
- Dry all clothes in a dryer that vents to the outside or use a clothesline
- Cover dirt floors in basements and/or crawlspaces with plastic or
other type of vapor barrier.
- Repair all plumbing leaks, roof leaks or problems, and cracks in
foundation walls as soon as possible.
- Ensure that soil and landscaping near the structure’s foundation
are graded away from the structure.
- Install floor drains or sump pumps in basements as necessary.
- Keep the temperature inside the home comfortable—not excessively
hot in the winter or cool in the summer. Drastic changes between indoor
and outdoor temperatures can contribute greatly to moisture problems.
Further precautionary steps can be taken to control moisture in the home
environment during initial construction or any subsequent renovations.
The New England Asthma Regional Council has developed excellent guidelines
for building healthy homes and also offers links to numerous other healthy
homes building resources.