Depth of footing for cinder block garden wall

Can anybody supply some convincing info or a link regarding the required footing depth for a cinderblock wall that will be two or three courses in height? I'm talking about 8x8x16 blocks that will be mortared in place. North Carolina. The real question is, even though the wall will be relatively light, does the footing still have to be the code-approved depth because of frost potential? The contractor already poured a 3.5 to 4-inch footing (after we agreed on 6 inches) and I have to decide whether to get him to rip it out and go deeper. Thanks.
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My first reaction is to withold payment and have him do as he agreed or send him on his way. At the same time, you ask about footing depth, then describe footing size. After wondering about that, I would like to know about horizontal and vertical reinforcing.
If it were my wall, I would want to have a footing placed below the local frost line, a minimum 7 inches deep and extending two inches beyond the masonry on each side. I would, for such a light wall consider a single reinforcing bar at the center of the footing cross section and extending the fool length. I would place vertical reinforcement every 24 inches to keep the masonry from overturning. How do you intend to protect the top of the masonry from water intrusion and freezing?
TB Charleston SC
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A 2 ft high wall that doesnt support a structure doesnt even need a footer, So what if it sinks a bit. A block wall suporting a small 10x10 shed doesnt need a footer. A footer on a garden wall a waste of money.
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I'd check out websites for garden block manufacturers. Plus, I'd use that type of product, not cinder block, as they are very attractive and available in a variety of styles, go together without cement, etc., while cinder block is about as ugly as you can get. I think you'll find that the manufacturers generally don't require footers, the product is designed to go on a well drained, compacted base. Anchor concrete is a supplier here with a website.
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I can only give you my experience with walls. I built field stone walls 2.5 ft high for the purpose of flower beds. that was 3 years ago. I am now rebuilding each one the right way. Field stone or cinderblock, it doesn't matter. Freezing water will move them. You can either set a footer below the frost line or supply drainage under the shallow footer with gravel(preferably pea gravel) to remove all water. The theory is the soil below the gravel will push up when frozen but the gravel will compact before the wall moves assuming the weight of the wall is is enough to push back on the gravel. Sorry, I wish I could be more scientific. Another point is if you are building a wall, you are probably holding something back(soil?). Now you have a horizontal push. It will tip your wall ! Again, backfill you wall with gravel to remove the water. I know a professional wall builder who insists on a backfill of 3 ft! I did 1 foot and have been ok so far(2 winters in Pa....frost line is 4 feet where I live). I have no idea what your frost depth is in North Carolina, but I'm sure you do. If it's not that deep or other provisions made for the removal of water, you'll spend the next summer or two doing what I did! Trust me, it cuts into your beer time.

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B wrote:

inches. Make him do it over, period. Doesn't matter if 3.5-4" is code approved. The contract was for 6".
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North Carolina has landscaping wall code? Cool. Got a link?

Surely you have a written contract. Get them to rip it out and start all over, guaranteed to have a better job done then.
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In general, the footing needs to be on undisturbed(*) earth, and below the frost line for your area. some kinds of soil heave around seasonally with different water content, and those present special problems.
(*) Undisturbed or packed down by someone who knows what the hell they're doing, which someone's you and I are not among.
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I am not a wall expert but I did a good bit of research on this topic about 3 years ago.
Blocks laid with mortar are not your best choice for any type of wall. Dry laid blocks which allow the water to pass through are your best choice.
In my area which seems to stay about 1 year behind the latest codes, there are no code requirements for "non-essential" retaining walls. A garden wall is "non-essential". That said if I were to build it I would build it to last. I would use the same standards as a normal retaining wall.
The footer should be below the frost level for your area, six to eight inches thick and at least twice the width of what you are going to lay up on top of it. In this case and 8" block would need a 16" front to back footer.
In your case, if you contracted for a 6" thick footer, that is what you should have gotten. How you handle it is up to you. Contact your local building inspection department if you need a source to cite for your actions. Or use this link for 665 hits of reading pleasure:
http://www.google.com/search?hl=en&lr=&q=%22retaining+wall%22+%2Bfooter
Best wishes
Colbyt
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Yes, it's ugly. This cinder block wall will serve as the base for an artificial stone facade.

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m Ransley wrote:

That would be OK, if it sank or heaved evenly, but that's unlikely, given moisture and other differences along the wall. As an alternative to removing the present footing, the OP might look into "frost protected warm foundations," and lay horizontal foamboard in a shallow trench outside the wall, then backfill the trench with soil.
Nick
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I would consider not mortaring any wall and using real stone or the manufactured paver types so water will flow through. Ive seen many walls built some 50-70 yrs old that are fine without mortar or even footers. Building a solid sealed wall will fail, a breathable wall wont. Water pressure will destroy it and the stone you cement to it.
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Nick if the wall is properly angled it will stay even , drainage is key through the wall, Settling, unless soil is different, changes in composition from area to area which is unlikely, there is no reason for any settling difference.
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replying to B, Maxx wrote: It should be atleast a 1' by 1' footing with 2 bars of Rebar running parallel with footing should have uprights every 24" in footing tied to the running rebar.those should be set on 2"X2" concrete adobes You need a base of some sort to hold wall from eroding. Do it right and you won't have to fix it when it shifts years from now.
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On Wednesday, September 7, 2016 at 5:14:04 PM UTC-4, Maxx wrote:

This thread goes back to 2005. unfortunately the OP didnt go back and fix the footer. a couple years later he was napping by the wall, and got crushed when it fell over......
hiskids are suing the person who put in the footer for a billion dollars.........
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