# Rigid perforated pipe - holes up or down?



## 47_47 (Sep 11, 2007)

Holes down


----------



## weberus3 (Mar 9, 2009)

Ok I'm confused? I thought that the reason for the corguated pipe behind the wall was to take the water away from the wall to keep it from wicking into the wall. So if the holes are facing ten & two (facing up) that would alllow the water to come in and carried away on the solid bottom. If the holes are on the bottom (4 & 8) how would the water come into the pipe to be carried away? Also the use of a sock over the pipe to keep soil and rock out of the pipe facing up allowing water to filter in, right? Help me figure this out..


----------



## Bondo (Dec 8, 2007)

weberus3 said:


> Ok I'm confused? I thought that the reason for the corguated pipe behind the wall was to take the water away from the wall to keep it from wicking into the wall. So if the holes are facing ten & two (facing up) that would alllow the water to come in and carried away on the solid bottom. *If the holes are on the bottom (4 & 8) how would the water come into the pipe to be carried away?* Also the use of a sock over the pipe to keep soil and rock out of the pipe facing up allowing water to filter in, right? Help me figure this out..


Ayuh,.... Water takes the path of least resistence,...

Holes Up, dirt falls in, holes Down, water flows out...

Drainage tile with the sock has slits, not so much holes...
OP is usin' leach field tubes...


----------



## concretemasonry (Oct 10, 2006)

Socks are not always a benefit, since if you backfill with the wrong soil, the higher velocity of available drainage water that is created by the slits and sock causes the fines being concentrated locally and cause problems. A french drain is not intended to carry collect and carry water away quickly since water moves quite slowly through soil. If you screw up on drainage, downspouts you should really put in a drain and positive drainage through a solid pvc pipe.

There are many old "french drains" that have been functioning for centuries because of the attention to materials. I played golf at a course where the groundskeepers kept discovering fully function "french drains" (with open jointed pipe or just a good mixture of sand and gravel) installed before they were born that maintained uniform soil moisture conditions for low areas.

Since water follows the rule of gravity, the holes in the bottom of a drain with proper backfill without maintenance. The lower the collection point, the more water will be removed, providing drier soil the absorb the moisture for drainage later.

Socks and slotted flexible pipe are good for retailers (cheap, easy and minimum shelf space because they can sell a "canned"package). If you are short term resident (less than 5 or 10 years) or flipper they many be an easy no-brain solution. - With slots, you do not even have to know what is up or down (like my geographically disadvantaged wife - LOL).

Dick


----------



## AllanJ (Nov 24, 2007)

At some level undergound the soil will be saturated. This level is the water table and can vary depending on rainfall and can also vary depending on soil composition and consistency resulting in varying as you go horizontally a few feet.

When the water table is below the underground drain pipe you really don't care whether the pipe carries away anything.

Once the water table rises above the levels of the holes in the pipe, water will enter the pipe and (should) be carried away by the slope of the pipe.

Socks work acceptably on corrugated pipe but will tend to clog quickly if put directly on smooth pipe. The sock can cling to the smooth pipe and then only the half inch circles of cloth directly over the holes will admit water and are easily clogged by silt.


----------

