Preventing Water Damage to Concrete Slabs and Foundations: Drainage Solutions

Proactively keeping water away from your foundation and slabs is an important process to ensure the long life of your building’s foundation and concrete flatwork.  In many cases a few simple steps can be taken by property owners to prevent water intrusion or the over saturation of soils that lead to settling foundations and concrete slabs.

We all know that water runs downhill; it will find the path of least resistance to the lowest point before settling on solid ground.  When the soils around your concrete are the lowest point is when we see problems with water intrusion or slabs and foundations damaged due to compromised base.  Always make sure a well compacted layer of dirt is sloped away from all structures and concrete pads at a minimum of 2% grade.  Just sprinkling topsoil or landscape rock is not going to solve the problem, remember, water is sneaky, it will find the path of least resistance to the lowest possible point, if you have a well compacted layer that is sloped directly back to your concrete you are only hiding the problem by covering it with topsoil or landscape rock.  We recommend a layer of topsoil, 3”-6” thick, compacted and sloped away from the concrete.  Ensuring proper grade around your property is the first line of defense against water damage, it prevents irrigation water, rain water and run-off from finding its way towards your home.

Secondly it is important that your home have adequate gutters, installed correctly and enough downspouts to support the size of your roof.  Gutters are useless if they are not cleaned on a regular basis, leaves, branches, dirt, birds nest and other foreign objects will build up and create a dam, causing the gutters to overflow and water to drain where it isn’t intended to.  Not only can this cause damage or water intrusion to your home but it can also damage the gutters as they are not designed to carry the extra weight of debris.  Having gutters and enclosed downspouts isn’t enough, the downspouts need to be draining at least 10’ (20’ for basement homes) from the perimeter of the house.  Inexpensive downspout extensions can be purchased at home improvement stores to increase the length of these drains, while they do help they are typically not long enough to move water far enough away.  Redco can also install underground downspout extensions that are a permanent solution to moving water away from your home.  Be cautious when installing standalone downspout extensions, if they do not move the water below the frost line ice can cause water to back up in the downspouts and water issues will persist.  Make sure that water is completely contained from the time it hits the gutter until it drains away from your home.  Downspout chains allow water to splash on your home or near the foundation causing potential for water intrusion or settling.

If water continues to be an issue when the ground is properly graded, and downspouts have been extended the third line of defense against water damage is a comprehensive drainage system to move and keep water away from your structure.  There are countless ways to install drainage systems including sump pumps and french drains.  We have found that the most cost effective and successful process is the installation of dry wells or barrel drains tied into your downspout system.  These large, empty barrels are buried below the frost line and placed on free draining soil, when a large amount of water is discharged from your roof these barrels capture the water and contain it while it slowly and naturally seeps into the ground.  These barrels prevent soggy spots in your yard because they are far below the grade of your lawn, they use the natural system of water absorption but in a controlled environment.  These barrels can be completely buried under ground, or have a grate or a pop-up drain installed on top of the barrels.  We recommend a pop up drain for 2 reasons, if there is so much water the barrel is filled this pop-up acts as an over flow to release the extra water into your lawn instead of backing up into your drain system near your home, pop ups also act as an access point in order to clean the barrels.  Just like your gutters these barrels require yearly maintenance to ensure they remain free of debris in order to maximize the water retention area and free draining material on the bottom.  Dry wells can also be installed as a standalone drainage solution anywhere you have a problem with standing water including window wells or planter beds.  The possibilities of dry wells are vast, using the same principles as a dry well, storm water capture systems are also available that allow you to capture and store run off and recycle it as irrigation water.

Typically, Redco does not recommend french drains or rock filled drains for residential applications as we have found them to be a short term solution.  French drains are a trench filled with rock and pipe that allow water to slowly dissipate.  They do work and can be an effective solution in some cases.  However the size required for adequate water capture is 5 times the size of a dry well discussed above.  They also capture dirt and debris which fills the voids between the rocks that is meant for drainage.  The only way to clean a French drain is to dig it up and install new clean rock.  We also see French drains installed improperly more often than not.  When a French drain is used against a building’s foundation make sure the depth of the bottom of the drain is at least 2’ below the bottom of the footing.  Placing a French drain above the footing allows water to saturate the solid soils footings need to be seated on and causing potential for foundation settling and leaking basements.

Like any other building maintenance water drainage is an important and ongoing process to prevent larger problems in the future.  Investing in a permanent plan now and performing the necessary continuing maintenance will minimize the potential for costly future repairs.

These solutions can scaled for any size application from a small town house to a large commercial structure or parking lot, Redco can install and help maintain the right drainage solutions for your property.  Contact us today for a free consultation and estimate.