Why a French Drain Needs Filter Fabric

I wanted to go over an engineering bulletin that I have about geo textile filter fabric.

We’re not going to get all geeky. It’s a five-page engineering bulletin on our fabric so I thought I’d share it with you, guys. Obviously, this is meant for industry insiders for the most part. But without getting into all the formulas and boring everyone to tears, basically it goes on to say that the purpose of our French drain filter fabric is to permit the free flow of water while retaining soil particles behind the fabric so that we are preventing the contamination of our drainage stone. That’s basically what this is all about. There’s also a little diagram that they give.


Do You Need Filter Fabric for a French Drain?

This diagram here was done on a road construction scenario so highway edge drain is what this is. They show a pipe and they show a burrito wrap of geo fabric, and then they show all the native soil. They got a magnifying glass and they’re zooming in on the fabric. So you got your drainage stone on the left, you got in the middle of that magnifying glass, the non-woven geo-textile, double-punched fabric, and then you have your soil on the right side of that magnifying glass.

French Drain Filter Fabric Works Better and Better Over Time

Now this diagram of a French drain is immediately after construction, so that’s how it looks. Now it’s not going to perform its best immediately after install. The French drain will perform, but it won’t perform its best until all the sediment washes through this double-punched fabric. Yes, we need the sediment to wash through. I get people emailing me pictures all the time and they’re freaking out because they see all this sediment inside their sump pump system, and I’m giving them all kinds of reassurance it’s doing what it’s supposed to do.

The reason why our geo filter fabric works better and better and better is because, as time goes on and more sediment washes through the non-woven geo-textile, double-punched fabric, the better the soil filter zone that is formed becomes, this soil filter zone that forms between the non-woven geo-textile fabric that’s double punched and the native soil. That is key, along with hydrostatic pressure, and you have all kinds of different things that make this extremely geeky. We’re not going to even go there, but everybody’s always asking, “Can you show us why this fabric works so amazing?” because everyone that’s used it gets the same results. They’re fantastic.

Always Use Filter Fabric for the Best French Drain

The reason why our fabric works so well is because it’s double-punched. And the longer you have your system in, the better the soil filter zone that’s formed becomes. This is how this works. Immediately after construction, it’s not going to work its best. You got to get all that sediment to wash through it. As time goes on, and it’s washing sediment through that non-woven geo-textile fabric that’s double punched, you are going to create the soil filter zone. When that forms, you are going to get some out-of-the-world performance that you just can’t even believe because the contractors that have switched over to our non-woven geo-textile double-punched fabric, they cannot believe how well it works. This is why it works so well, and they won’t go back to not using non-woven geo-textile fabric that’s double-punched.


Purchase French Drain Man’s Non-Woven Geo Textile Fabric