Home Inspection Tips - Moisture Problems and Crawl Spaces

Any home inspector can tell you that mostYour home's crawlspace needs a minimum of 1
crawlspaces have moisture problems. There are twosquare foot of ventilation for every 150 square feet
different types of crawlspace setups--vented andof crawlspace floor area. Vents should be within 3
non-vented.feet of the corners allowing for cross ventilation.
Vented crawlspaces have vents that allow for crossCould your insulation be installed upside down? You
ventilation and the home's sub floor is insulated alongmay have insulation in the flooring. The paper side of
with the pipes in the crawlspace to prevent freezing.the fiberglass insulation should face the heated living
There's a vapor barrier on the ground and vents arespace and be placed against the sub flooring.
closed in the winter time. A small heater or heat tapeOtherwise it will trap moisture between the sub floor
may also be used to help keep the pipes fromand the paper and hide moisture damage. A properly
freezing in addition to insulation on the pipes.set up non-vented crawlspace won't need insulation.
With non-vented crawlspaces, foundation walls areIs your moisture (vapor) barrier damaged or loose? It
insulated, but the sub-floor isn't. The vents areshould be a 6 mil thick poly vapor barrier on your
blocked off with insulation all year long, and a vaporcrawlspace ground and should be overlapped and
barrier is in place on the ground. Air is conditionedsealed around columns and walls. This keeps ground
with a dehumidifier. A small heater and pipe insulationmoisture vapors from rising up into your framing.
may still be used.If you have a sump pump installed, make sure it is at
Problems arise when there are inadequate or no rainthe lowest point in the crawlspace. All areas should
gutters. Did you know the average roof lets go ofeasily drain to it. Inspect your pump regularly. Does it
1,000 gallons of water during 1 inch of rain? You canwork automatically? It should be in a plastic cylinder in
keep water from falling along the foundation andthe ground and eject water outside, away from the
finding your crawlspace by using solid rain gutterbuilding and not into the septic or sewer system.
covers to cover the gutter opening. This allowsIf your crawlspace is non-vented, you must have a
water to come in by curling under the cap.dehumidifier, and the collected water should be piped
Unfortunately, mesh and screen covers get cloggedto a sump pump or condensate pump. If you don't
up or collapse.do this, you'll have to dump water daily, and who
Do downspouts end along your foundation? Theywants to do that? Incidentally, buy a good quality
need to let water run 6 feet or more away fromdehumidifier with an adjustable, automatic setting so
your home.it does not run all the time.
Does your terrain slope toward your foundation?Is your crawlspace kept neat, clean and accessible?
Water must be directed away from the homeInspect it often for signs of moisture or mildew.
because water can cause serious foundation damage.Check with the local code official for any repairs you
Do you remember to open the vents when weathermight need. Don't underestimate the importance of
warms up? Your house needs to breathe. Low decksyour crawlspace and what you can do to prevent
and shrubs can block vents and make them useless.that all too common moisture damage.