At Drycrete Waterproofing we tell our customers we’re not stopping water we’re managing where it goes. If you’re facing water intrusion issues caused by hydrostatic pressure, then Drycrete can help. Over the years we’ve installed thousands of French drain systems using the highest quality materials and expertly trained technicians.
Groundwater refers to the water that is present beneath the Earth’s surface within the soil and rocks. The level of groundwater surrounding a foundation can vary depending on factors such as rainfall, soil composition, and local hydrogeology.
Every foundation is a giant bowl in the earth. Groundwater collects in the bottom of that bowl and gets trapped underneath your basement floor. That water can’t drain or percolate fast enough so hydrostatic pressure builds. The water pushing up on the bottom of your slab can cause seepage, flooding, and cracking in your slab.
You can never hope to stop groundwater from collecting near your foundation so it’s important to put systems in place to control where it goes. One such system is a French drain. There are various benefits to having a French drain installed:
Think of this like a pressure release valve. Groundwater will take the path of least resistance. When it’s trapped underneath your slab with pressure building, it’s forced to push through the porous concrete, the cracks in your slab, and the joints near your foundation walls. However, when you have a 4” perforated pipe and a 12” by 12” trench filled with crushed stone, the water has plenty of space to travel away from your slab.
This is one of the often overlooked benefits of having a French drain system installed in your home. After installing a French drain it is not uncommon to hear, “It rained for the past two days, and our sump pump hasn’t turned on once. We’re usually ankle deep in water. What’s going on?” When Drycrete installs a French drain system we dig a 12” to 15” deep and 12” wide trench, then fill it with crushed stone and a 4” perforated pipe. This extra capacity allows water to collect in your French drain but never rise high enough to turn on your pump. After the rain stops the water will simply recede back into the ground.
When preparing to install a French drain system the first thing we do is break apart the concrete and dig trenches around the perimeter of your basement. We dig our trenches anywhere from 12” to 15” deep. The reason we do this is because when we concrete over the trenches, we use 2” to 3” of 4000psi concrete as opposed to 1/2” to 1-1/2”. This additional depth gives you the freedom to build walls right over the top of your French drain with no worries of damaging the system.
Drycrete uses 4” perforated pipe in 10’ lengths. This allows us to put a pitch on each section, ensuring the correct flow of water. You’ll often see French drains installed using corrugated pipe or rectangular gutter type systems. They both suffer from the same issue. Proper pitch is very difficult to establish and maintain.
Corrugated pipe is flexible, allowing for ultimate adjustability, but lacks the rigid structure needed to ensure consistent pitch throughout the system. The corrugations in the pipe also create sticking points for sediment and debris to get trapped and build up over time.
The rectangular gutter system has the same pitch issues, and the reason is the rectangular design. A pipe that is meant to carry water in any capacity is usually round because it allows you to rotate the fitting to maintain proper pitch around corners. Flat rectangular pipes will not allow you to do this.
Drycrete Waterproofing uses ¾” crushed stone to surround the drainpipe providing various benefits:
With every French drain system, we install what’s called PolyCove. This dimple board acts as a flashing material, diverting any water that makes its way through your porous concrete walls or through a leaking crack or tie rod, into your French drain system. If you have plans to finish your basement you can also tuck your vapor barrier behind the PolyCove, preventing water from ever coming in contact with the inside of your finished space.
The first step is to break the concrete around the perimeter of your basement (about 12” wide), then dig down and excavate the material (12” to 15” deep). We’ll need about 5 feet of clearance around the perimeter of your basement.
Then we’ll start lying a bed of ¾” crushed stone in the trench.
We’ll install 4” perforated drain pipe, starting at the lowest point of your basement, which is where your sump pump will be located. We’ll make sure each 10’ length of pipe is properly pitched towards your sump pump.
Next, we’ll install our PolyCove dimple board along the pipe.
Then add in the rest of the ¾” crushed stone and pour 2” to 3” of 4000 psi concrete over the top of the trench and blend it with your existing concrete.
Give the cement 72 hours to cure and you can move your belongings back to their original locations.