French drain placement against a retaining wall, question.

[Baitball Blogger]

Okay, here's what I don't understand. To build a retaining wall properly, they say you should bury the first row, or at least, half-bury it for stability. And then, you place a french drain behind it.

I have studied up french drains and understand about placing the drain pipe on the non-woven geo-fabric, dump drain rocks on top and wrap like a burrito. What I don't understand is exactly where the pipe should fall, in relation to the wall. For example, if I put it on the same level as the buried row of bricks, then there is no way for the weep pipe to run downhill. So, it's obvious the pipe needs to be on level with the top of the second row from the bottom, so you can grade it downward, to allow proper drainage.

Does this sound right?

[Bluethroughu]

1. My husband said bury the first row completely,

And make sure it was set on a bed of sand to get level. The drain pipe can be at the second row, and make sure pipe has pitch out, rule of thumb is 1/4" per foot.

[Baitball Blogger]

3. Perfect!

I overkilled the paver base and made it five inches with a very compacted one inch level sand. Here in Florida, this seems to work well for drainage.

[Bluethroughu]

13. That means the wall won't be moving EVER!

Great job.

[DonaldsRump]

2. We had an issue with a wooden fence that was badly leaning

because (or so we thought) it was being pushed by a huge amount of soil against it. I researched this issue last year, and if I recall, there are tons of videos etc on YouTube on issues like this.

It turned out our issue had nothing to do with drainage, so we wound up not putting in a french drain running the length of the fence.

Use a search like this in Google: french drain retaining wall

[Baitball Blogger]

4. I already watched five youtube videos with that search request.

Learned quite a bit with each one.

[DonaldsRump]

9. And one more tidbit that I got from Google

"And by the way, the French drain was named after its inventor, Henry Flagg French, and not the country France. French was a 19th century lawyer from Concord, Massachusetts whose book, Farm Drainage: The Principles, Prospects, and Effects of Draining Land, is credited with popularizing this type of draining solution."

[Baitball Blogger]

10. I did not know that.

Thanks for the info.

[DonaldsRump]

11. Me too!

In 2003, because of the US backlash against France for not supporting the Iraq Invasion, I wonder if the RWNJs were boycotting French drains too, in addition to French's mustard, French wine, and stuff like renaming French Fries to "Freedom Fries". Perhaps they renamed French drains to "Patriotic Pipes" or "Liberty Lines"?




One thing you have to give the right wing credit for: they are consistently despicably stupid and mean through the ages!

[Baitball Blogger]

12. They certainly give comedians plenty of material.

[CottonBear]

5. Professional advice: retaining walls greater than 4 ft. in height should be designed by an engineer.

Proper design of surface and sub-surface runoff is needed to prevent structural failure of retaining walls.

[Baitball Blogger]

6. Oh, yeah. Mine is only two feet.

I over killed the project, partly because I wanted to learn the techniques. Anything three feet or more would have required city approval. Our slope is much smaller and it's a perfect size to be a sitting bench.

[CottonBear]

7. I love dual purpose walls! Extra garden seating is always nice.

An extra wide wall cap of 18”-24” (retaining or non-retaining wall) is a good feature for leaning back or lying down.

[Baitball Blogger]

8. +1