Pour Concrete Retaining Wall...

ruskent

Normally i just build srws and stick to small masonry structures. This job has come my waywhere the is a walkout basement. Customer wants a patio. This means we need to build a 1200 face foot retaining wall with heights up to 8 feet and bring in around 800 yards of fill.

Personally, i'd like to do poured concrete walls and cultured stone them. I think it would match the house much better. For some reason i seem to think it will end up costing less then SRW since backfilling will go much faster not having to worry about geo grid.

So if we do poured walls, ow would the walls be engineered? What type of footing? How thick the walls? I had engineering done for a 3 ft masonry wall. Engineer wanting the T footing, then 2 feet of CMU block underground. When it was all said and done, for a 3 ft wall i had 6 feet of wall/footing underground.

Basically, i want to see if i can even meet the constraints of the budget building it this way. I know i will need a engineer. I just want to see if anyone could give me a ballbark per a sq ft # just for the poured walls so i can see if it makes some sort of sense to build the patio this way. Also i need to give somee kind of ballpark $ on the retainer agreement so i can start the design process.


Thanks Matt

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ruskent

One more pic. And oh yea. I know all that dirt the excavator put against the foundation has to be reexcavating for compactable fill.

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concretemasonry

For an 8' height, I imagine a poured wall will be much more expensive. As you know it is very costlt to build a good retaining wall in a cold climate.

Somewhere down the line, someone will have to come up with the detail design required for a poured wall that will show the real cost. For any rigid wall, you will have at least 3' below grade in your area and then face building and compacting during the wet spring weather.

Prepare to look at a SRW wall when they see the cost comparison.

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ruskent

If we go SRW we will use Techo Bloc quarry stone 4 and 8inch combo. On similar jobs we end up being in the $70 range atleast per a face foot. This is if we are doing 4-5 ft pulls of grid with imported fill.



The main reason i want to go concrete has to due with the way i want to intergrated the outdoor kitchen, ralings, etc with the walls.

lukachuki

Matt you get all the good jobs.

Actually I'm getting ready to do a similar wall on a smaller scale here in a month or 2. I'm sure we will learn lots. In our case we don't have a choice as it is what the customer wants. A faux FL Wright house which has been fun.

Good luck in figuring this and let us know which way you go.

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ruskent

How are you constructing the wall?

On any project, labor seems to be the largest expense. Yes concrete and rebar is very expensive, i just think by pouring the wall will save alot of labor.

neolitic

And the most expensive "labor"
will be when the engineer
smacks that stamp on the plan!

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Chris Johnson

Call the guy that did the original basement for a number, with that white stuff on the ground there I would bet he's not over booked right now. Not saying that's going to help with the price, but even though it's a small job he may jump at it.

Do you not use geo grid there for poured walls? It's designed in my area anything over a certain height and we need to put it in, sometimes placed at various heights i.e. 8' wall, geo grid @ 3' and 6'

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Tscarborough

70 bucks for SRW is good money, but assuming everything else is equal, I do not think you will be able to pour a concrete wall for less than an SRW.

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Driftwood

RUSK , I would go with a 10" thick wall w/re-bar 8' tall . $235.00 lineal foot

Guessing footing! 12"x36" w/re-bar $73.00 lineal foot, dug by hand

Price includes pump. good luck, lets help one another!,pass it on

Price from Home Tech Cost estimator 2007 cost area Ca.11 [No. Ca.]

Good luck ,Driftwood

ruskent

Driftwood, those prices do not seem bad at all.

Now another option could be to build concrete peirs, run steel beams and decking and pour a 4 inch concrete slab. I know this is another pricey option, but would eliminate ALOT OF wall and fill.

tgeb

We did a poured concrete retaining wall last winter/spring but priced it in Sept 06.

Our wall was a total of 39' long and footing was 5'2" wide 1' thick w/lots of steel.

Some of the wall was 8' high and some was 6' high, 12' thick w/lots of steel. I divided it all out and it came to about $44/face foot.

But we also waterproofed it and put drain tile behind it and backfilled it most all the way with stone.

The price would be more today.

One thing to watch for when doing this sort of thing is to make sure that when you do these retaining walls you are not exposing footing to the elements that is not "frost footing".
I have seen work done where the HO wants a nice flat area next to the walkout doors, and digs the slope away. Well usually the builder only puts in the minimal amount of frost footing and the rest is protected by the soil slope. Take away the slope...footing heaves!

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Driftwood

Rusk, I'll give You My 07 Est book when My 08 gets here. e mail Me

ruskent

We are still going back to forth on this project. Client felt my srw price was to high. He had the company who poured the basement walls work up a price for just the walls. THe guy said he could do the walls for around 30k. He just guesstimated the correct way to build the walls??? I told the homeowner the # is useless unless it is from a stamped plan.


Some people just do not understand that a retaining wall is alot different then a basement wall. The guy was also going to tie the wall in to the basement wall with rebar? Is that a good idea?

Tscarborough

Exactly the right tack. Compare your SRW engineered wall to his engineered PIP or CMU wall, and you win, every time.

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Snow Man

It is a normal part of the process. His only mistake was not doing it as soon as he wrecked the forms.
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Hoven

Call the foudation contractor back again. Pour this wall with a footing and key way. I would also tie a steel rebar mat for the wall interior. Your also gonna want deadmen poured back into the hill to strengthen. 800 yards is alot of new material to keep back. I tend beef these up. There's always time to do it right the second time.

concretemasonry

Hoven -

How many foundation contractors can provide a complete, signed design that is accepted by code people? there is a big differebce between a free-stabding retaining wall and a basement that has a fllor to resist the top from moving in. - The client is just trying a crude approach to get the price down without knowing a thing.

The amount of material (yards) behind the walll is not as important as the height of the wall, the type of soil and the specs for the backfill.

If you just use dirt for backfill, it probably would fall on deaf ears, which is common to people with nothing between the ears.

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Driftwood

You have more patience than Me !!!

ruskent

It takes this long to close these deals now. House is not done yet. It has the base coat for stucco on now. But it is not dry walled yet. The electrian has been holding them up.



I get these jobs because I stay on the client. It takes people along time to make choices. It is taking a year now to close alot of deals.