Dear bob4141-ga;
Thank you for allowing me an opportunity to answer your interesting
question. I have little doubt that one of these issues will be your
problem, but the trick is going to be finding out which one:
POOR CONSTRUCTION/ POOR MATERIALS
It would seem that after 40 years an owner would know if his home was
poorly constructed or not, but the fact is, what was considered
well-built 40 years ago is not always the case today. Materials and
methods used back them could very well have exceeded their maximum
effective lifespan. In short, they?re just plain worn out. Tars once
used to seal a wall didn?t have fibers in them 40 years ago, nor did
many of them contain sealants like latex or rubber. Bricks were
probably made better back then but there has since been a number of
superior mortars developed that are almost certainly not the kind used
in the construction of your home. So you see, wear and tear alone can
be a factor in leaking basement walls.
SHIFTING SOIL/EROSION
If there has been some significant shifting of soils, like a series of
heavy rains or snow melts over the years or even a minor earthquake,
sharp stones could very well have damaged the wall by grating against
it. On the other hand, the opposite is also true and voids can develop
near the wall trapping water that has no place to go except inside.
See below:
SINK HOLE, DEFILE OR DIVOT
For example, if a low spot or void has developed near the outside wall
it might be trapping or attracting water and forcing it into or down
upon the exterior wall. It doesn?t take long under this kind of stress
that the water eventually moves inside with you. A major cause of such
a void under the ground is a dead tree. If the root system collapses
or the tree and root ball is physically removed, a void is often
created allowing water to collect beneath the surface. Gravity and
time will eventually work against the wall and the water sometimes
seeps through.
CHANGE IN WATER TABLE
If you have had flooding in your area in the past 10 years or so the
water table might have risen or the underground water flow and volume
changed directions. If your exterior basement walls are in the path
you?ll need to consider redirecting the flow through evasive drainage
measures or perhaps even digging up the basement walls and re-treating
the exterior. In addition, if your nearby creek is not draining
properly for some reason (flood, beavers, downed trees, etc) the water
table around your house could have changed substantially in a very
short period of time.
CHANGE IN RUNOFF DRAINAGE, DIRECTION, VOLUME.
For example: If your sidewalk or driveway was built pitched ?toward?
the house, or has cracked or shifted so that it is now tilted (even
slightly) toward the house it will drain water right down your
basement wall. Eventually, if left unattended, it WILL find a way in.
After 40 years, if would almost definitely have found a way in under
these circumstances.
CRACKED OR BUCKLED WALLS
This really speaks for itself. If the wall is damaged, even on the
outside where you can?t see, water is likely entering the masonry and
finding a way in.
BASEMENT FLOOR IS CRACKED, SEPARATED FROM THE WALL, OR NO LONGER LEVEL
If you have developed an opening at the floor between the wall and the
foundation, it won?t cause a leak in the wall. What does cause wall
leakage is when this damage goes undetected and the wall deteriorates
from the ground up, and water makes it?s way through the wall at a
point higher up than where the original separation occurred.
HYDROSTATIC PRESSURE
This is simply water building up against the wall until the force or
movement of the water (or sheer gravity) enables it to penetrate the
wall at the weakest point. At 8.33 lbs per gallon, fifty gallons of
water weighs about 416 lbs. So you can see how much pressure would be
applied to the wall over a long period of time from just the weight of
the water alone ? and that?s not even factoring in force or other
extraneous pressure that might occur.
DEBRIS IN THE DRAIN TILES OR MISALIGNED DRAIN TILES (SOMETIMES
REFERRED TO AS ?WEEPING TILES?)
These conditions can trap water, cause it to erode the wall and
eventually seep through a weak area. Note: Once this water builds up
it will find the places of least resistance and come through the wall
there, so keep in mind that the place where the water is coming into
the basement might actually be some distance from where the water is
building up or flowing toward the exterior wall.
DRAIN PIPES CLOGGED, DAMAGED OR INAPPROPRIATE.
For example: If you have no extension on your sump discharge pipe
excess water can pour out at ground level and then run right back down
the outside basement wall.
GUTTERS, TROUGHS, AND EAVES
Assuming you have downspouts on the gutter work of your home, take a
look at the end of the downspouts where they meet the ground. Do you
have extensions on them? If not, and the water is probably not being
carried far enough away from the house before it is released. Instead
it is probably draining directly out of the end of the downspout where
it goes straight down along the side of the exterior basement wall.
Same goes for your gutter troughs along the edge of your roof and the
eaves of your roof. If the water is not successfully draining into the
downspout it could be running down the side of the house and straight
into the ground onto the exterior basement wall.
If you have no extension on the downspout of your house gutters,
gutter leading water off your roof and away from the house, it will
simply drain straight down into the ground and down the basement wall.
IMPROPER BACKFILL
While the backfill job might have worked for many years, it may have
settled, washed away or even be causing the pressure on the wall
itself. Same with the gravel ? it may be washed away, compressed and
not allowing water to drain or causing pressure against the wall
itself.
WALL OR FOUNDATION COATING
The treatment applied to the exterior wall and foundation might have
outlived it?s maximum effectiveness or it might have been substandard
or incorrectly applied to begin with.
CONDENSATION
Let?s not rule out the possibility that your basement is really
leaking. It may be coming from another source such as condensation.
Condensation within the basement can come from a number of sources
including washing machines, improperly vented dryers, a basement
shower, sweating cold water pipes and leaking pipes. Condensation can
also form when warm basement air comes in contact with cold outside
walls and basement floor. The walls become wet and take on the
appearance of leakage. Sometimes it can be fairly profound.
MILDEW, MOLD, BACTERIA
These can erode grout and eat away at mortar. If your area has a high
prevalence of mold spores than this might be something to take into
consideration.
TREES, ROOTS, ROCKS
Trees can sometimes spread roots over an enormous area. If roots are
working into the walls or pressing against them, crack can occur and
allow water to enter. Roots can also move large rocks, slabs and even
boulders toward your basement walls causing the same type of damage.
It might not be apparent from the inside but what?s happening on the
outside of the wall can be serious. Don?t discount that old oak tree
20 yards from your house as being the culprit either. Again, some
trees have roots that are absolutely huge.
I hope you find that my research exceeds your expectations. If you
have any questions about my research please post a clarification
request prior to rating the answer. Otherwise I welcome your rating
and your final comments and I look forward to working with you again
in the near future. Thank you for bringing your question to us.
Best regards;
Tutuzdad-ga ? Google Answers Researcher
INFORMATION SOURCES
B-DRY BASEMENT WATERPROOFING
http://www.b-drybasementswaterproofingnepennsylvania.com/leaking-basement-repair.html
(these guys are in Northeast Pennsylvania by the way)
UNTITLED GRAPHIC
http://www.ci.mil.wi.us/citygov/dns/pdf/maps/basement_leak12.pdf
ONTARIO ASSOCIATION OF HOME INSPECTORS
http://www.oahi.com/inspectors/m-basement.asp
ALLSTATE ? WET BASEMENT
http://www.allstatehomeinspection.com/wetb.htm
TIPS FROM THE INSPECTOR
http://www.homecrafters.net/check.htm#WET%20BASEMENT
SEARCH STRATEGY
SEARCH ENGINE USED:
Google ://www.google.com
SEARCH TERMS USED:
Basement, leak, leaking, leakage, weeping, walls, condensation, wet, causes |
