A poured concrete wall with rebar does not need to be thick to be strong.
How thick should a poured concrete retaining wall be.
In general poured concrete basement walls that are 8 feet tall or less and have no more than 7 feet of soil pressing against them from the outside function well at a thickness of 8 inches.
Concrete retaining wall footing size.
The footing should be at least as thick vertically as the wall s planned width.
For example if you are pouring a retaining wall that will be 12 inches thick and will use wooden planks that are 1 1 2 inches thick for your forms you ll need to space the stakes about 15 inches apart 12 inches for the retaining wall plus two pieces of 1 1 2 inch thick wooden board.
In general the top of the stem of any cast concrete retaining wall should not be less than 12 inches for the proper placement of concrete.
Poured concrete foundation walls that are less than 8 feet tall and have soil outside that is 6 or 7 feet deep against the wall can often be 8 inches thick and function quite well.
Walls that have bends greater than 30 degrees at no more than 20ft intervals are stronger than straight walls.
For walls up to 3ft 5 5 inches thick works fine.
As laag points out the wall needs a sufficient footer.
These consists of a concrete or masonry wall of uniform thickness vertical wall reinforcing and transverse footing reinforcing are all designed for the lateral shear and cantilever bending movement plus the vertical weights of the wall footing and earth fills.
This can add several inches to the wall s thickness dimensions and can vary depending on the severity of exposure soil type and reactivity etc.
As soon as you go higher or have greater depths of soil pushing against the wall you need to increase the thickness to 10 inches.
Most landscape contractors in areas of heavy rainfall or weather extremes avoid fine poured concrete work due to its challenges.
Poured concrete walls can be tricky to install but look great with the architectural elements of a modern house.
A poured concrete footing for concrete block or brick walls should be at least twice as wide as the planned wall.