Cutting into a bank....??

[fire72]

Soil type is a big factor here. When I cut into the hill for my barn, I had a roughly 4' to 5' vertical bank, with the idea that the back wall of the barn will be the retaining wall. The project stalled for financial reasons, so the cut has just been sitting there unsupported. It's been that way for nearly two years, with no slump. This is in a heavy clay/shale soil. There's no way that would still be standing in a silt/loam or loose gravel soil.

When the project gets back on track, there will be drain tile along the base of the wall. The top of the bank will be sloped to drain to either end. With the stability of the soil, I'm not too concerned about the strength of the wall, although the final specs have yet to be determined.

 

[scoutcub]

There is lots of good info here, but it looks to me like
the question has already been answered. Behind the
house is a beautiful retaining wall. Wouldn't you
would want something similar behind the garage? or
combine them into 1 long wall?


How tall is that retaining wall behind the house?

Dutch -

They did put a very nice retaining wall up behind the house, it's a good 6' tall. I was planning on continuing the curve around to the garage, but not behind it......as you would never see that nice expensive block!
However, Not sure if I want to cut the bank 10' behind the back of the garage.....I was thinking more like 2-4'.......hmmmm.....

 

[2manyrocks]

If this is a garage for your cars, I remember reading a suggestion in a landscape planning book that it's good to layout the space requirements for cars using a garden hose. There were some dimensional requirements that got to be fairly large to turn around, etc.

My question is whether you have enough space to reslope what you have so you don't have to use a retaining wall and so you can still cut grass when you're done.

There comes a point in reshaping land when a dozer is the best tool. My neighbor did some work for me at $60.00 an hour, and it was the best bargain I've had in a long time.

 

[roamerr]

That is quite a bit of digging/grading. I would question if a poured rear wall and partial sides would be better and be part of the building.The nice thing about a garage partly underground is that it adds some heat in the winter. The bad thing is that you have to do the drainage right or you will have a wet garage. A few feet of french drain is rarely enough...

 

[Tim_in_IA]

That is quite a bit of digging/grading. I would question if a poured rear wall and partial sides would be better and be part of the building.The nice thing about a garage partly underground is that it adds some heat in the winter. The bad thing is that you have to do the drainage right or you will have a wet garage. A few feet of french drain is rarely enough...

I was thinking the same thing. instead of a retaining wall just have a higher curb wall on the back side of the garage.

 

[davygp38]

I wouldn't worry too much about it. We put in a pole barn for the RV last summer. I had to cut into a hillside like yours, but a bit steeper and higher. I cut back ten feet beyond the barn and then sloped the ground away from the barn, about one foot in the 10' distance. Water drains down the hill into the swale and away from the barn into the swale. The ten foot gives me plenty of room to mow between the barn and the bank.

I sloped the bank low enough that I can mow it.

I would not bother with a retaining wall or drain tile.

Ken

I have to agree. I Live in an area with nothing but this type of topography. The hillside, is graded back, the ground around the garage is sloped into the hillside, the swale that is formed between the two, is drained into the yard. The only problem I ever saw, is when the swale is to slight, and over time due to mowing, and regular maintenance, the swale got smoothed out, causing water collection. The biggest reason was that the guy who bought the house, did not realize the swale was there for a reason, and did not maintain it.

 

[radioman]

Wow- you got alot of dirt to move. Do you want to have the new garage at same level as the house ? I would- and this means alot of dirt to be moved. Hopefully you have a place to put it.

IMHO- Since this is on a deep hillside, runoff is not really a concern until you start putting up retaining walls. I would have a poured wall, with french drain at the top,behind of the wall and bottom, front of the wall. you have excellent slope for drainage anyways. Since you need a concrete floor, have the same contractor pour the floor and wall. You should have at least 10 ft or more between back wall of barn and finished retaining wall . the ground behind barn should be sloped in a Vfrom center for more drainage.

 

[scoutcub]

Looks like nearly 50/50 on retaining wall or not. I like the idea of backfilling against the garage for the added insulation. An open area behind the garage would interfere with a path I'd like to have to the left of the garage, going behind it along the treeline to the back of the property. My property goes up to the treeline. How about conventional construction with a block/poured back wall? I've seen garages like I want to install with a block back wall into a bank that's failing, the ground is pushing the wall in. Unsure of the drainage behind it... again, I'm trying to do it as inexpensive as possible.....

 

[schmism]

put me in the pour a reinforced concrete rear wall of the garage and be done with it.

less expensive than a retaining wall with less dirt to move.