# Tall basement walls - poured concrete



## mopanic (Apr 18, 2017)

I am looking at building a walk out basement home on a steep lot. Normal design with garage facing the street. The back of the garage wall will also be the back of the basement and this will be tall due to the slope of the ground. Currently it is looking like it will be 14' or so. I believe I will need to get an engineered wall if taller than 10', any advice of this is correct. Thoughts on most affordable methods? From initial talks it appears that an engineered wall in the 14' range will be quite expensive due to required footer width/depth and the amount and size of rebar being called for. Another alternative looks to be bringing in fill and compacting it, thereby raising grade level and needing a smaller wall, something in the 10' range. Just looking for general thoughts from anyone who has dealt with this on the most affordable options. For clarity, we are talking about skipping the traditional poured concrete basement floor and doing a sub floor crawl space for basement level with steps leading down to back yard. 

Thanks.


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## dayexco (Mar 4, 2006)

mopanic said:


> I am looking at building a walk out basement home on a steep lot. Normal design with garage facing the street. The back of the garage wall will also be the back of the basement and this will be tall due to the slope of the ground. Currently it is looking like it will be 14' or so. I believe I will need to get an engineered wall if taller than 10', any advice of this is correct. Thoughts on most affordable methods? From initial talks it appears that an engineered wall in the 14' range will be quite expensive due to required footer width/depth and the amount and size of rebar being called for. Another alternative looks to be bringing in fill and compacting it, thereby raising grade level and needing a smaller wall, something in the 10' range. Just looking for general thoughts from anyone who has dealt with this on the most affordable options. For clarity, we are talking about skipping the traditional poured concrete basement floor and doing a sub floor crawl space for basement level with steps leading down to back yard.
> 
> Thanks.


what type of construction sales you in?


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## TimNJ (Sep 7, 2005)

mopanic said:


> I am looking at building a walk out basement home on a steep lot. Normal design with garage facing the street. The back of the garage wall will also be the back of the basement and this will be tall due to the slope of the ground. Currently it is looking like it will be 14' or so. I believe I will need to get an engineered wall if taller than 10', any advice of this is correct. Thoughts on most affordable methods? From initial talks it appears that an engineered wall in the 14' range will be quite expensive due to required footer width/depth and the amount and size of rebar being called for. Another alternative looks to be bringing in fill and compacting it, thereby raising grade level and needing a smaller wall, something in the 10' range. Just looking for general thoughts from anyone who has dealt with this on the most affordable options. For clarity, we are talking about skipping the traditional poured concrete basement floor and doing a sub floor crawl space for basement level with steps leading down to back yard.
> 
> Thanks.





?????
If you are going for walk out basement then why wouldn't you do slab on grade?

If you do a walk out with a crawl space under it, that is going to cause your wall to be taller than needed and it won't be a "walk out basement".


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## Seven-Delta-FortyOne (Mar 5, 2011)

Yes, a 14' tall wall will need to be engineered. :blink: 

And yes, the price and complexity generally goes up after 8'.

I was bidding a job a couple months ago, and the owner was looking at a 12' basement. Going from 8' to 12' more than doubled the cost of the basement. The footings were going to be over 42" wide. They ended up going back to 8'.


You can look into block as an option. You save the cost of forms, but spend more on labor. Might be a wash, I don't know. Have your foundation sub bid it both ways. Or if you're doing it on house, just price it both ways. I've found block to be cheaper for me on several occasions, but I do my own block.


YMMV



Delta


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## griz (Nov 26, 2009)

Please learn to use the space bar and enter keys.....:whistling

How about talking to your Civil Engineer......:thumbup:


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## SevenHills (Jul 22, 2015)

As others have said, you need an engineer to look at a 14' tall wall. Building up the grade to make the basement smaller also probably has a lot of cost if you're trucking in fill. One thing not to forget about: if you make a really tall ceiling in your basement, make sure you have room for a larger length of stairs.


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## dayexco (Mar 4, 2006)

Something else to consider. We always stubbed sewer services into lot at 9 feet deep. Here, top of foundations had 2 be 2' higher than highest top of curb elevation on property. 

With 9 and 10 foot tall basements, some were forced into installing ejector pumps for the sewer to work.


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## hdavis (Feb 14, 2012)

14' from the ground to the first floor on the back of the building? That's either really steep or a ridiculously deep basement. I wouldn't consider putting a foundation on a side hill like that without engineering. Depending on the soils report, you may be putting in piles, and building on them. No way to know without the engineering studies.


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## jlhaslip (Dec 31, 2009)

A walkout basement can easily be 14 feet or more up here.
Nine foot interior wall plus below grade beam for frost protection to footing is easily 14 ft. More in certain spots where the frost goes 8 feet down.
32 inch x 12 inch footings are not uncommon for a two storey.


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