[SquareWest]

Hey guys,

I'm a homeowner (not a pro) with a dilemma. Before anyone suggests hiring a pro - great idea, I agree - I'm currently unemployed so I'm trying to make the best use of my free time combined with lack of funds!

Sorry this is long, but I'm trying to be as detailed as possible.

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Summary: I want to put in a short (2 feet high+/- by about 30 ft in length) retaining wall between my house and neighbors driveway (max distance between the two: 8 feet in width) to correct a negative grade and put a french drain down the middle to remove water. Could use some advice.

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I live on a city street with a small lot and all the houses are very close together. For whatever reason, either due to settling or idiocy, my neighbor's driveway and lot sit above mine by a few feet and apparently have been graded directly into the foundation of my house for much longer than I have been here.

The trick of course is to alleviate this situation. I can't build any dirt up because it was already 2 inches or less from the wood siding (and of course his yard is higher than mine anyway).

I've started digging it out:


This is facing from front of the house to back with the driveway I'm speaking of on the right. My lot, from the angle of this photo, slopes from right to left, and from back to front.

I've already started digging it out, as you can see. The bush at the rear is going to be going too.

The total width from my foundation wall to the side of his concrete driveway is almost exactly 8 feet. The dug out portion in the photo is about 4 feet wide. Current depth is about 1 and 3/4s feet at the deepest point.


I would like to run a drain down the middle and deposit the water either in the front yard or perhaps to his driveway if he'll let me, since it grades down from there.




This photo is from the same direction of the first, but from the street. I'd like to run the retaining wall to where that first dip is - my current digging is behind that (I haven't taken it all the way out so I can hide it from the street for now).



This image is from the back of the house (around the corner). You can see where I've started digging at the corner of the sun porch and the neighbor's driveway beyond that. The slope continues there and I'd like to end the retaining wall with a short 90 angle jut out to hold that in place (making an 'L' with a long top and a very short base). I'm also debating whether I should slope that flower bed in front of the sun porch back/left towards my trench, or forwards/right towards the patio (out of photo, it eventually has levels that grade downward as well - that downspout in the photo runs underneath the patio and empties out at my driveway on the other side).



This shot is of the same trench, just shot from back to front, for perspective. Again, the trench will be continuous - the bush is still there because I was debating about trying to move it - apparently it's been there for 40+ years, I feel bad about just chopping it to bits.

So, my questions/comments are:

1.) I'd like to make the retaining wall out of railroad ties. It seems to be the cheapest (locally I've seen them for $18 each) for what I'm trying to do, and if it lasts 10 years I'll be ok with that. Is there anything better for a similar price, or anything I should know/take into consideration?

2.) I'm thinking with the wall and gravel for drainage on the backside, max open space between retaining wall and my foundation will be 6 feet (I'm allowing 2 feet for wall and gravel backfill). Is that enough space to fit a french drain in to be sufficiently away from my foundation?

3.) With them being so close together, will I have any issues with the trench for the french drain settling inward (from the pressure of the retaining wall above) and allowing the retaining wall to slope? - or, do I need to put in a lower foundation for the retaining wall, perhaps even below in depth of the french drain trench?

4.) With the wall being only 2 ft or so high, it doesn't seem like I need any deadmen. But, the neighbors driveway is next to it. He doesn't park where the wall would be - but will that added load of him driving on it be a problem?

5.) If I did need deadmen, could I dig a gap underneath his concrete pad, slide it in, and then pack it back with soil? - OR could I shore the wall up by putting posts in front of it (in my trench area) and securing them with concrete footers?

6.) If the french drain can't be placed far enough from the foundation, couldn't I just put plastic tarp or something underneath (instead of landscape fabric) and run ALL of the water out to the front yard, instead of letting some soak in in the trench area?

7.) In the first picture, underneath the first window (approx.) the gas line runs through about an additional 9 inches (guesstimate) below what I've currently dug. I'm thinking I may need to run my french drain underneath of it. Aside from not chopping into it (duh) are there any issues I should be concerned about with this setup?

8.) Also, I'm thinking if I use a single railroad tie row as a footer for the wall. If it does go as a low as the gas line, is it an issue to notch the footer to allow the gas line through?

9.) Any other hazards you can think of?


Again, sorry for the long post, but I wanted to be thorough. I've researched a lot on both french drains and retaining walls but my situation seems to be unique in that I (think I) need both, in such a small area, with a driveway so close next to it.

Thanks in advance for taking the time to read this and for any insight you can provide.

[zullo-design]

build the wall higher than his driveway so you can keep his water off your property than just grade your property along that side so your water goes to the street if possible.

[zullo-design]

also dont undermine his driveway to put in dead men, dead men help but without proper cribbing aren't as effective especially since there is no way you could compact around them enough.

Plus if your neighbor found out you would be screwed.

[natural12]

Do what Zullo suggests. I would add the it would be best to put the drainage on the back side of the wall (neighbors side) to catch the water. This may have been suggested but I am too lazy to read your entire post.

[agla]

There is good driveway drainage to the street like Zullo said. I agree that you should be able to surface drain this by a swale rather than a french drain.

A 2'high rr tie wall needs some kind of strengthening.

Providence?

[SquareWest]

Originally Posted by agla

There is good driveway drainage to the street like Zullo said. I agree that you should be able to surface drain this by a swale rather than a french drain.

A 2'high rr tie wall needs some kind of strengthening.

Providence?

Hmmm I would love to just do that instead of bother with the drain. But my foundation is early-20th century with zero waterproofing. Would enough move away with a swale to keep my basement from having moving water?

Second to that is that sun porch in the back has a very poor footer and the concrete block foundation has settled. Would a swale be enough to keep it from settling more?


And what kind of reinforcement would you suggest for the wall if I can't put in deadmen? I thought perhaps wood posts in front with concrete footers below.



Thanks again guys.

[agla]

The swale will work if there is a good pitch from the house to the swale and the swale pitches to the road fast enough to keep the water moving. It looks quite do-able.

It actually should be more effective than a french drain. because you are not allowing or actually relying on the water to slow down, be absorbed into a trench, reach saturation in order to enter the pipe, and then move away as the pipe runs downhill. The swale should move almost all of the water quickly without it being absorbed into the ground next to your foundation. It looks like you can do a straight shot to the street.

Vertical posts are better than nothing for reinforcing a 2' tie wall.

[Kovu]

Another idea is to lay a french drain behind the wall along with a membrane that starts from the boack of the wall and underneath the newly installed french drain. This will help keep water from permeating your wall and perhaps making it to your foundation wall (however, I would put two pipes in so that you don't create pressure that might make your wall fail if you get a 100 year type rain).

However, if you're still concerned about the possibility of water infiltration into your basement through the foundation wall may I suggest adding another french drain along the side of your foundation wall deeper than the french drain along your new wall. After digging down along your foundation wall for this pipe you could apply a "Dry-lok" type "paint" to help prevent water infiltration.

Also, price Turf Block or Permeable Joint Pavers for the run between your new wall and house. This type of block, with a run-off type base like crushed rock and with a french drain, would dramatically enhance run-off capabilities.

[SquareWest]

Thanks a lot for all the great responses, guys.

I think I'm going to do the wall and try the swale route since it's easier, and then if that doesn't work I'll try a french drain.



One last question - any thoughts on the gas pipe running through there? Any concerns? (see my questions at the end of the first post for clarification)




Thanks again!