25 mm for each 1 ft 300 mm of wall height for the amount or buried block that is needed.
Retaining wall base.
600 mm wide the length of the wall the depth of the trench will be 6 in.
More information on retaining walls where the base trench steps up a slope.
Retaining wall base trench.
Retaining walls are designed to hold up a surcharge of soil such as a sloping hill or raised planter box.
Using a tape measure decide the length and the width of your retaining wall then mark off the area with the garden stakes and string.
When excavating the trenches for the wall block keep in mind the bottom row of blocks should be buried about 1 inch for every 8 inches of wall height.
Follow the block manufacturer s instructions for wall height limits.
The most important step is the base preparation.
The interlocking retaining wall block can be used to build walls up to 24 to 36 inches high depending on the size of the block.
Avoid having downspouts pointed at the retaining wall and if it s against the house keep soil and mulch well below the siding.
The preparation of the base upon which the first layer of block are to be placed is critical to building a well placed stable retaining wall.
150 mm plus an additional 1 in.
The success of your retaining wall depends on a level base.
To keep the blocks on your retaining wall level and structurally sound you need a base layer of several inches of well compacted sharp gravel.
To create a solid foundation dig a trench for the first course of your interlocking retaining wall blocks to sit in and make sure the ground remains even throughout.
Retaining walls can be constructed using a variety of materials from poured concrete and large timbers to natural stones even bricks.
Also called drain tile at the base of the wall.
A level base on which the wall sits.
If you have the option it can be easier to excavate and lay the lowest course before excavating the trench for the next step.
Below is an overview of the different types of walls and these common components.
This is standard for all.
A handheld tamping tool can really help in getting the gravel level but you re right one stray stone can throw off the entire operation.
By doing this you will provide strength and stability of the wall.
All retaining walls share some common building components in their construction.