Wet Basements Part Three

So, the basements wet, what to do?   There are several "fixes" to this problem.  As noted in he earlier blogs, repairs can be largely dependent on the type of construction used for your home.  For simplicity, we'll explore a typical, 1950's ranch type home.  These fixes apply to some degree to many older homes as well.

Step one is examining exactly what is causing the wet basement.  This past summer in NE Ohio, we had record rainfall in just a few hours.  Lots of storm sewers filled up to capacity, and they backed up into basements.  This problem is out under the street and there's not too much that the individual can do, as it's related to the sizing of the city storm sewers.

If you've got the more typical seepage from walls etc, start with a walk around the house.  Are all the gutters clean?  Are the downspouts connected, clear, and draining into crocks leading to storm sewers or extending to a lower area on your property?  In the city, most homes will have the downspouts tied in to the storm sewers.  Sometimes, as these clog, people opt for surface drainage, adding a splash block, or directing the water a few feet from the foundation.  If your yard is flat, this isn't helping your damp basement.  The roof is collecting large amounts of water and depositing it right where you don't want it- along the basement walls.



Above is a classic example.  The downspout line might have become clogged, so a flex line was installed to divert the water away.  This became disconnected, and now the water just spills against the foundation.

If you do have abandoned underground drains, as indicated by clay or PVC "crocks" with no downspout running into them, your first option is to have these lines cleaned.  This is done by jetting water into them.  I recommend companies that have camera snakes.  They will determine with certainty the condition of these lines.  You can then make an educated decision on how to proceed

I'll continue this discussion in the next blog.

Wet Basements Part Two

In my first blog, I talked about wet basements and clay tile foundations.  This time, I'd like to talk a bit about other foundations and problems associated with them.

Older home foundations come in all shapes and sizes.  Among the oldest I see as a home inspector are ones constructed out of field stone, sandstone etc.  These appear to be very roughly stacked.  The "good" side was placed towards the inside.  If you could remove the dirt, the outside would appear to be even more roughly stacked.


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Here's the outside of a very early fieldstone foundation.

These foundations were never meant to keep out water.  For example, on a new home, with either a poured concrete foundation or a concrete block foundation, the exterior will be parged- a sort of stucco like masonry material that is used to seal any voids.  Often you can see this close to the ground on a foundation.  It's only used below grade.  The next step is a sealant material that today is sprayed on- a black tar/paint like material. After that, some builders may install foam insulation boards below grade.  This is optional and debated in some circles.  It does nothing for drainage.

What is sometimes done for drainage is a drainage plane may be installed.  This is a board like material that basically creates a small void between the foundation wall and the soil/gravel backfill.  Any water that makes it to the wall simply runs down via gravity to the footer drains (which we'll discuss next).

The footer drains are what is really carrying water away from your basement.  These are laid on the exterior of the footers, just below the level of the floor slab.  The purpose of them is to collect water that drains down through the soil and towards your basement.  Water will take the path of least resistance.  Footer drains are generally 4" pipe with holes to allow water to enter.  They are then tied into your storm sewer or taken to another termination point on your property, the storm ditch etc.  Gravel is then backfilled to allow easy passage of water towards the drain, and to help eliminate some of the pressures that can occur when soil and clay gets wet, freezes and expands (the result can be a crack to your basement wall!).

The trouble is, if you live in an older house, you probably don't have the current standard of footer drain, parging, or backfill.  For example, the sandstone foundation house probably won't have a footer drain or be parged on the outside.  Homes of this type were typically built in the 1800-1870 period, and a dry basement wasn't a concern.  No mechanical were there, nobody needed a recreation room, there wasn't time for that sort of stuff, so basements were simply used for storing canned goods.  The more cave like, the better.

Later, brick, cinder block, clay tile, concrete block all enter the picture.  With standard sizes, foundations can be built quickly and easily, but they still weren't necessarily worried about seepage.  As the years progressed, it became typical for "drain tile" to be used where we would not use a PVC footer drain pipe, the kind I mentioned earlier.  These tiles were what the name says, simple tiles, fluted on one side, so that if you laid them face to face, you'd have a small gap, roughly 1" to allow water to drain through.

As the name suggests, they were simply tiles, so not connections between them, they were just laid in a row along your footer.  The walls may or may not have been parged, and may or may not have had any type of sealer put on.  That all depends on the decade the home was built.

The photo above shows round clay drain tiles, circa 1950-60's.

With modern construction, after the footer drain is installed, the hole will be backfilled to almost the surface with gravel- just enough dirt on top to plant in.  100 years ago, it's possible no gravel was used.  It wasn't until the 1960's that more than a foot or so of gravel was used.  The amount has grown over the past fifty years to the current standard.

So, you can see, how wet your basement is can be largely dependent on how your home was constructed.  Your expectations for a dry basement have to be tempered to this somewhat, but there are ways to solve these problems.  In  my next blog, we'll begin discussing these methods.