How To Install a French Drain
What is a French drain?
French Drain – Where did it originate?
The French Drain is one of the most frequently searched terms when it comes to drainage. However, most of the information we see posted on the internet by contractors and homeowners is not accurate. Here are some misconceptions about what is a French drain:
1) The French drain was developed in France because the homes there did not have roof drainage (gutters) so an open trench of perforated pipe and crushed stone would direct the roof water away from the foundation.
2) The French drain is an outside trench directing water away from the foundation.
3) A French drain is that small channel about ½ inch that’s open and collects water around the perimeter of the floor. This is called a hydro-gap. When the home was built, the builders installed this type of flooring to channel water to a sump pump in most cases. However this method does work and water just sits in the gap and causes more harm than good. With water just sitting stagnant in the floor it creates humidity and bacteria-which then causes MOLD.
The truth of the matter is that it was named after Henry F French, a judge from Cambridge, Massachusetts who wrote a book in 1859 called Farm Drainage. In that book he wrote a chapter called Cellar Drainage. In fact, in the book it shows how he recommended installing interior clay tile drains (2″ clay tile laid side by side in a trench around the perimeter of the cellar surrounded by tan bar.
A classic shallow drainage system, the French drain is often the best and simplest start to a complete basement waterproofing campaign. Keeping a dry basement in your Philadelphia and Bucks County home should be a top priority for every homeowner, as excessive basement moisture could result in a cracked foundation or a severe black mold buildup.
A French drain is an easy way to avoid a wet basement. You may be able to install one yourself, but hiring a basement waterproofing contractor might be the best way to go, particularly if you’re covering a wide tract of land, or if the system must be installed in the basement crawlspace itself or under the foundation.
Here’s the process to installing a French drain, outlined in a few easy steps
Determine the drainage path
This is where you find out whether the job is simple enough to do yourself, or you need a basement waterproofing company to do the job for you. Start from the spot where water is collecting, or where you want to relieve flooding. This could be inside your basement or along your foundation. Then trace a route to the lowest part of your Philadelphia property, or a retention pond if you have one. Remember that the system needs at least a one percent grade to drain water effectively. The only physical principal involved here is gravity, so be sure to keep it in mind at all times when installing a French drain.
Be careful: There may be tree roots, other buildings, concrete pathways or underground utilities in your path.
Excavate the trench
Think of it as a moat around a medieval castle – only instead of keeping out foreign invaders, the trench in a French drain is meant to carry water away from your Bucks County home. Dig the trench in a U shape, about six inches wide by an eight to 12 inches deep – though your measurements may vary depending on the size of your flooding problem.
Fill the trench
Lay about two inches of gravel in the trench, leaving enough room to lay pipe on top, then another layer of gravel above that. Again, how much gravel you use will depend on the depth of your trench and the extent of the area to be drained.
Lay the pipe
The pipe is the most important aspect of your French drain. In the area to be drained, you’ll need perforated pipe, so the water can enter the drainage system. But once you get past the flooded area, you’ll switch to a solid drain pipe, so the water doesn’t leak from the system.
Cover the pipe with gravel
It’s important to use gravel in a French drain system, and not just back-fill the trench with dirt, because creating a porous system through which water can escape is paramount. If you covered the pipe with dirt, it would just turn to mud once another flood came along, and be carried out through the system – or clog it. Stick to washed gravel or very coarse sand.
Sod over the unperforated portion of pipe
This can easily be hidden from view with sod, since the French drains purpose isn’t to collect water but to carry it away.
A French drain is the simplest and most direct solution for relieving flooding in any area of your Philadelphia, NJ or Bucks County home, whether it’s the basement, around the foundation, or a low-lying area in your yard. Just like the mustard, whether it’s actually French or not isn’t important – what’s important is that it works.
Right Way Waterproofing serves clients with basement waterproofing, basement remodeling and mold remediation needs in throughout the Delaware Valley, in Philadelphia, Delaware and New Jersey, throughout Bucks County, Montgomery County, Chester County, Burlington County, Mercer County and Delaware County, including Langhorne, Newtown, Yardley, Bensalem, Warminster, Morrisville, Lower Makefield, Trenton, Newark, Wilmington, King of Prussia, Newtown Square, the Main Line and Bala Cynwyd.
