Foundation drainage

[RMechEng75]

Working on a residential project on a sloped property. The current footing drain pipe is pitched and drains to day light at rear of property. There is a proposed retaining wall (4ft tall, 14 ft long) to be butted up/ perpendicular to house foundation. Can the retaining wall foundation drain tie-in/ connect to the house footing drain before terminating to daylight or do they have to terminate to daylight separately?

Thank you
Rob C

 

[EireChch]

Possibly, but I have my reservations as a retaining wall drain is more likely to get blocked than an residential drain. What is the a house footing drain, what is it draining?

post a sketch of what you are proposing to get better answers.

 

[RMechEng75]

EireCHch,
See attached sketch.

The property is sloped to the rear. The proposed retaining wall height has changed from 40 inches down to 26 inches. The existing house footing drain (yellow) slopes to the rear of the property and terminates to daylight at grade. The proposed retaining wall to level the rear yard and will have its own drain (green) that terminates to daylight thru the wall at the lowest point. Can the existing footing drain (yellow) connect to the new retaining wall drain (green) or shall it terminate to daylight thru the wall independently?

 

[Canuck65]

Clear sketch!
My preference would be to keep the green and yellow systems separate. Extend the yellow/house system beyond the retaining wall. They could daylight beside each other and that would be fine.
In my opinion, the less preferable option of connecting the yellow system into the green system could be made manageable by oversizing the green system.

 

[EireChch]

If you are using an appropriately backfill, perforated drain and drainage sock then personally I dont see an issue at all tbh. Its a drain for a 26 inch high wall...

if you are really concerned you could put a rodding eye on the ling before the connection, but then it may as well be as easy to add a separate connection.

 

[RMechEng75]

thank you all...

LAST QUESTION: What weight of geo-drainage filter fabric (non-woven) do you recommend?

 

[EireChch]

any non-woven fabric will do, i would go for the cheapest.

 

[RMechEng75]

thanks again

 

[ClemsonVet]

agree with Canuck65 response. extend the yellow line rear past the wall and daylight.

 

[RMechEng75]

thank you.. Yes, playing it safe, yellow line will go out to daylight.