Cross section of a retaining wall a cinder block retaining wall is only as straight and solid as the base it s built on.
How many inches of concrete for a retaining wall.
Avoid placing the retaining wall where downspouts are pointed to keep standing water from forming inside the wall.
How to build a concrete wall figure a.
Top this with 1 inch of coarse sand or small gravel before constructing the wall proper.
For example if the wall is 24 feet long and the capstones are 8 inches wide then the number of capstones needed is 24 8 36.
A 4 inch slump the measure of the distance a wet concrete cone will fall is typical.
You may need to buy a few more in case some stones should break or need to be cut.
If concrete is not being used to build the footing as is common for drystacked stone walls and very short walls the footing can simply consist of about 6 inches of compacted base material like angular sharp edged gravel.
Consider getting several professional estimates to get the best labor cost and find the right company for your project.
Planning a retaining wall.
Before building a retaining wall plan it out.
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.
If you re building a retaining wall then check out our retaining wall calculator.
For example if the desired wall height is 6 feet the wall should be embedded below grade by 7 8 inches.
For a stacked block retaining wall that s no higher than four feet a trench filled with three inches of crushed rock will help keep the wall from shifting and settling.
Tall wall excavate a trench deep enough to accommodate 4 to 6 in.
Retaining wall cost varies by material.
Calculate the rows and columns.
Be sure to account for this when measuring the height of the wall.
Of leveling sand and half the height of the first course of blocks.
Adjusting slump at the job site will damage the concrete.
Of compacted base 1 in.
Just enter the dimensions of your wall project and the concrete block calculator will figure out how many blocks are needed.
Poured concrete is typically the most expensive followed by wood timber and then stones and pavers.
Most experts suggest embedding the first course of blocks below grade about 10 of the wall height to support the wall correctly.