Crawl space: Check crawl space for animal infestation, termites,
ponding moisture, or high moisture content; check foundation grilles for
adequate ventilation; seasonally close grilles when appropriate-in winter,
if not needed, or in summer if hot humid air is diffusing into air conditioned
space.
Foliage: Keep foliage and vines off buildings; trim overhanging
trees to keep debris from gutters and limbs from rubbing against building;
remove moisture retaining elements, such as firewood, from foundations.
 A vent may be added if there is none. Close grilles in the summer, if hot humid air is getting into air conditioned spaces. Photo: NPS files. |
Basements and foundations: Increase ventilation and maintain surfaces
to avoid moisture.
Equipment: Check dehumidifiers, sump pump, vent fans, and
water detection or alarm systems for proper maintenance as required; check
battery back-up twice a year.
Piping/ductwork: Check for condensation on pipes and insulate/seal
joints, if necessary.
Interior: Maintain equipment to reduce leaks and interior moisture.
Plumbing pipes: Add insulation to plumbing or radiator pipes
located in areas subject to freezing, such as along outside walls, in attics,
or in unheated basements.
Mechanical equipment: Check condensation pans and drain lines
to keep clear; insulate and seal joints in exposed metal ductwork to avoid
drawing in moist air.
Cleaning: Routinely dust and clean surfaces to reduce the
amount of water or moist chemicals used to clean building; caulk around
tile floor and wall connections; and maintain floor grouts in good condition.
Ventilation: Reduce household-produced moisture, if a problem,
by increasing ventilation; vent clothes driers to the outside; install
and always use exhaust fans in restrooms, bathrooms, showers, and
kitchens, when in use.
"Controlling Unwanted Moisture" an Historic Preservation Brief
