Foundation Waterproofing Basics: Interior Drain Tile
In the basement waterproofing business we have just one objective – keep your basement dry.
In that pursuit, we battle against not only the forces of nature – heavy rain, drought, hydrostatic pressure, soil movement – but against man-made obstacles as well, like poor construction, bad grading, clogged gutters and misdirected downspouts. We don’t go into battle unarmed, though; we have many weapons at our disposal, one of the best of which is interior drain tile.
Now, don’t get me wrong; a good basement waterproofing company is no one-trick pony. In fact, you should beware the ones who offer only one solution no matter what the source of the problem. A full-service basement waterproofing company will offer a wide range of products and services and will employ well-trained advisors who can diagnose a problem correctly and recommend the best solution, not just the one they have available.
What is Interior Drain Tile, Anyway?
First of all, there’s no “tile” – that term has stuck around from the old days when terra cotta roof tiles were used in foundation drainage systems. Today’s interior drain tile is perforated plastic pipe, preferably of the flexible, corrugated variety, that is buried next to the footings of a home’s foundation to carry off ground water before it infiltrates the basement.
To install interior drain tile, the basement waterproofing company first removes approximately a 12-inch strip of the concrete basement floor around the inside perimeter. Next, they dig a trench down to a point along side the foundation footings and put in a bed of washed gravel. If there is no existing sump pump, a hole will be dug and a sump basin installed.
The flexible pipe, wrapped in a “sock” of filtration fabric, will be connected to the sump basin and then laid in the trench all the way around the basement and connected to the basin on the opposite side. A covering of more washed gravel will be added to the trench and new concrete will be poured and finished to repair the floor.
A sump pump is then installed and discharge piping extended out of the house to a point at least ten feet from the foundation (or directly into a storm sewer if possible.)
Why is Interior Drain Tile Such a Good Basement Waterproofing Solution?
Interior drain tile works when ground water seeps into the pipe through the perforations and is carried to the sump pump and removed instead of seeping into the basement.
Because the drain tile is positioned next to the footings on the inside of the foundation, it is in a prime spot to alleviate numerous causes of water infiltration:
Hydrostatic Pressure – When water accumulates in the ground below a basement, the natural pressure of the water can force it up through even the tiniest cracks in a basement floor. With interior drain tile in place, the water flows into the drain pipe instead.
Cove Seepage – Water from a number of sources, including hydrostatic and lateral pressure and seepage down the outside of foundation walls can enter the basement through the cove joint, the place where foundation walls sit atop the footings.
Window Wells – Rain water can accumulate quickly in window wells, resulting in seepage around poorly installed or aging windows. Window well drains can be tapped into interior drain tile if there is no other convenient source of discharge to alleviate this problem.
So, it’s fairly easy to see why interior drain tile is such a great solution for homeowners. In an unfinished basement, it can be done quickly and with minimal disruption, with no excavation outside the home.
At U.S. Waterproofing we’ve installed miles of interior drain tile while assuring more than 300,000 satisfied customers that their basements will stay dry. If interior drain tile is the right solution for you, we’ll tell you so; if not, we’ll know the right way to keep your basement dry. Why not ask for our free advice?