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Discussion Starter · #1 ·
Ok, building a new home single story wood frame 28x40. It is sloped and will be about 2ft on the high side and 14ft on the low side. Building on a step footer. What do I need to do to reinforce the 8in block wall on the foundation?
 

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This is a very loaded question. Building step footings on slopes is tricky, and not something you wing or guess or at. So I really hope you don't take design advice from a chat room on this. In the real world, structures on slopes with step footings are designed to not only bear the weight of the structure, but also to resist the loads imparted from settlement. The way it works is a geotech firm provides a report to the engineer laying out the soil bearing characteristics and footing sizes, and then the engineer designs the footings and foundation walls.
 

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You have not given any information on the soil types and how much soil may be retained by the block wall you want to reinforce.

Too bad you do not have a code or engineer to protect you from yourself. You may have frost depth problems, but since you did not give even a hint of your location and make sure you have proper drainage and soil cover over the strip footings.

A 12' elevation difference on such a small home gives a hint of difficult construction and design. I assume the house is normal stick "cookbook" construction once you have a foundation.

Dick
 

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Discussion Starter · #7 ·
You have not given any information on the soil types and how much soil may be retained by the block wall you want to reinforce.

Too bad you do not have a code or engineer to protect you from yourself. You may have frost depth problems, but since you did not give even a hint of your location and make sure you have proper drainage and soil cover over the strip footings.

A 12' elevation difference on such a small home gives a hint of difficult construction and design. I assume the house is normal stick "cookbook" construction once you have a foundation.

Dick
Build site is Winston county Alabama. No frost or drainage issues. Yes, stick, cookie cutter style home. No soil retention. The 14ft wall will be on the low side of a slope giving the appearance of a walkout basement. I'm just starting my "research" to find out my options. Do I need "reinforcement ladders" every 3ft? Rebar and cement every other block?
 

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So you have a 21' high 8" wall? - Obviously you do not want or recognize a code or engineer to protect you.

You can do it, but I doubt you want to do it right. - Also, it is grout, not "cement" to fill a masonry wall.

Dick
 

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Discussion Starter · #9 · (Edited)
So you have a 21' high 8" wall? - Obviously you do not want or recognize a code or engineer to protect you.

You can do it, but I doubt you want to do it right. - Also, it is grout, not "cement" to fill a masonry wall.

Dick
Alabama follows IRC, no I don't want an engineer! Do you have any information to assist me, or do you just want to bash my post! What have I said that makes you think I'm not following code? If "filling" the center, why would you use "grout"... Where do you come up with a 21ft wall?
 

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Sorry about the 21'. I erroneously typed in the height/thickness ratio (14'x12 divided by 8") instead of the 14' height of the unsupported wall. The h/t ratio is used in many "model" codes to determine design and construction requirements.

The term grout is in your code when referring to filling the cores of masonry construction. Grout is used to fill voids in masonry construction and concrete is an incorrect term/material. Concrete is not used because it does not fill the voids completely and it is required to be more fluid to do the job and bond to the block and rebar. Cement is just a dry raw material that is used to make both grout and concrete.

I hope you do get some proof that you followed the IRC since is adopted the masonry design standard that I was involved with for about the past 20 years. If you have any future problems with disasters or failures you may find you are not covered by insurance.

Dick
 

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I don't think any advice from a registered engineer would be taken well.

Just make sure all parts of the footings will be deeper than the frost depth after any erosion along the slope.

The structural design of the walls and step footings supporting your house is not difficult if you know something about structural masonry.

Best of luck.

Dick
 

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Ok, building a new home single story wood frame 28x40. It is sloped and will be about 2ft on the high side and 14ft on the low side. Building on a step footer. What do I need to do to reinforce the 8in block wall on the foundation?
I am not an engineer or concrete expert but have just built a foundation in Tenn similar to yours but not nearly as high. Here is what I did and will try to post a photo. Footer was stepped and all block below grade was 12 inch changing over to eight inch block and brick above grade. As first course of 12 inch was being laid I used hammer drill and drilled many 5/8 holes Six inches deep into footer in center of block cores and drove with sledge hammer short pieces of 5/8 rebar to anchor wall to footer. After wall was finished I placed long rebar pieces in cores making sure they were going all way down to footer. Then had a pumper truck contractor from Alabama come to site and we filled all block cavities with a concrete mix made for block filling. It uses 1/2 stone and a little more water I. Mix to allow it to be pumped and to flow into block. All back filling around wall was done using 1 1/2 gravel and not dirt. Drain added on footer prior to back fill.
Also forgot to mention used some block reinforcing wire about every third course as wall was being laid. I don't know what more I could have done to make wall stronger.
 

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Discussion Starter · #15 ·
I am not an engineer or concrete expert but have just built a foundation in Tenn similar to yours but not nearly as high. Here is what I did and will try to post a photo. Footer was stepped and all block below grade was 12 inch changing over to eight inch block and brick above grade. As first course of 12 inch was being laid I used hammer drill and drilled many 5/8 holes Six inches deep into footer in center of block cores and drove with sledge hammer short pieces of 5/8 rebar to anchor wall to footer. After wall was finished I placed long rebar pieces in cores making sure they were going all way down to footer. Then had a pumper truck contractor from Alabama come to site and we filled all block cavities with a concrete mix made for block filling. It uses 1/2 stone and a little more water I. Mix to allow it to be pumped and to flow into block. All back filling around wall was done using 1 1/2 gravel and not dirt. Drain added on footer prior to back fill.
Also forgot to mention used some block reinforcing wire about every third course as wall was being laid. I don't know what more I could have done to make wall stronger.
I was thinking of doing every other cavity with rebar/concrete and horizontal reinforcing evert third block. But is it necessary, or just overkill? It yours a 1 or two story? What size and footer did you go with width and depth?
 

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I was thinking of doing every other cavity with rebar/concrete and horizontal reinforcing evert third block. But is it necessary, or just overkill? It yours a 1 or two story? What size and footer did you go with width and depth?
After thinking about it my walls are as high as yours. My slab is elevated three block on high end going to about seven block on low side, ten foot walls above slab level. The block as described make up the whole house. All internal framing is non-structural and roof is trusses. Footer is two foot wide with 12 inches thick concrete and two 1/2 inch rebars. If you take a look at "partial earth sheltered home" in project section on this site I have posted several photos.


In this photo you can see garage foundation being built in foreground.
 

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