Wednesday, February 6, 2013

Water in the basement

If its not the number one cause of anxiety for home buyers and sellers alike, its in the top five. Some of that anxiety may be mitigated with a better understanding of the systems in place to control that water and some of the more common areas of failure. 

Without question the most common cause of wet basements is surface water drainage.  This is something that can be easy to detect and relatively straightforward to remedy.  Common deficiencies are: 
-  Negative grading of soft surfaces - surface water drains back toward the house.  Many times this is caused by settling.
-  Negative drainage of hard surfaces - Sidewalks, patios, and stoops
-  Malfunctioning Gutter and Downspout systems - melting snow and rain is not moved away from the foundation.
-  Drainage systems are impeded by ice, roots, silt, have been crushed or there is a blockage down the line.

When surface causes are addressed and appear to be in working order, we look for signs of system failures that are a little harder to see.  An understanding of the foundation drain tile and sump pump system is required. 

The image above represents a general foundation water management design that has been used in homes for the last 50 years. 

The two circles represent drain pipes or "drain tiles."  These are open areas where water can collect and be moved to manageable areas.  There are generally drain tiles outside the foundation at the footing and inside the foundation around the perimeter of the footing leading into the sump croc which is the trapezoid with the arrow coming up and out. 

Outside and inside drain tiles are connected by "bleeder" tiles in the footing. This design creates a low resistance path to move water from outside the foundation to inside the foundation under the concrete floor and into the sump croc where it is pumped out of the basement and away from the house. 

Generally, when the sump mechanism or inside drainage system is not functioning properly, water is seen seeping into the foundation area at the base of the walls and up through cracks or openings in the concrete floor. 

Troubleshoot this system by starting with the sump pump. 
-  Be sure your pump has power! Sounds simple but storms take out power, breakers can be tripped, outlets may go bad, plugs may be partially or fully removed.  A back-up power plan is always a good idea.
-  Make sure the float is functioning by plugging the pump directly into the outlet and bypassing the float switch.  Floats can malfunction for many reasons and sometimes need to be adjusted within the croc.
-  If the pump isn't pumping, troubleshoot the pump.  Many times debris or a small stone can get into the pump and lock it up.  Otherwise it may be past its usable life and needs replacement.  They don't last forever.  It's a good practice to learn how to check your sump pump for proper operation throughout the year.
-  Inside tiles may be blocked with silt or concrete.  If the pump is working and water isn't flowing well into the croc, you may have inside drain tile problems. 

If your outside tiles are not functioning correctly you may see water forming further up the wall.  Many times, silt fills in these tiles and they can no longer move water to the inside tiles and into the sump croc.  It can take dozens of years for this problem to develop.  Contact a qualified foundation inspector to do more exhaustive testing. 

Lastly, water that originates away from the outside walls, and is more interior to your basement, is likely from other interior sources.   Keep in mind that, generally, in more modern construction, your clearwater sump system is separate from your sanitary system in your home.  This means your floor drains, where condensation from your furnace runs, and discharge from appliances like water softeners drain IS NOT connected in any way to your sump pump.  Circumstances may vary and if you are in an older house the sanitary sewer may be connected to the storm and sump system.  Check with a qualified inspector or contractor to best determine your unique situation. 

Through careful, and methodical, evaluation you can systemmatically begin to determine the root causes of basement water and quickly get on the road to repair.  To contact me for further information please visit:  www.integratedhomeinspections.com.

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