How to Build a Retaining Wall: The Foundations

HOW TO BUILD A RETAINING WALL: THE FOUNDATIONS

In this video we are going to learn how to lay the foundations in order to build a retaining wall.

They will ensure the solidity of the wall and mean that it is stable and therefore that it won't collapse under the weight of the earth.

The width of the base should be at least half the height of the wall, and it should be a minimum of 40cm (16"). If the retaining wall is one meter high (40") the base should therefore be at least 50cm (20") in width.

Before beginning the work it is important to check the weather forecast! The base needs a drying period of 2 to 3 days during which it is important that it does not rain.

In tis example we will need: a cement mixer, a wheelbarrow, a shovel, a spade, a pickaxe, a sledgehammer, a pair of pliers, a measuring tape, a level , a masonry ruler, a grouter, stakes, some string and a grinder,

Also remember the safety equipment

GLOVES

HELMET

PROTECTIVE GLASSES

We will also need remesh frames, rebars, annealed wire, concrete and gravel.

Remesh frames

Rebars

Annealed wire

Concrete

Gravel

Mark the position of the wall

Step 1: Mark the place in which you want to dig the foundation. In order to do this, place the wooden stakes into the soil at each end of the future wall. Stretch the string and attach it to the stakes.

Mesure the width of the foundations. In this case our foundations are 50cm (20") in width. Mark this line in the same way.

Dig the foundations

Step 2: Dig foundations of 60cm (24") deep in order to ensure they will remain sheltered from the cold during freezing temperatures. You can use a shovel and a pickaxe in order to dig, and a spade to ensure the sides are straight.

Step 3: Flatten the bottom of the ditch with a gardening tamper or the back of a rake.

Place the "hedgehog"

Step 4: Recover the bottom 10cm (3") with gravel or small stones. This part, called the "hedgehog" creates a stable bed for future foundations. Check the level using the masonry ruler.

Step 5: Now cut the remesh to the correct length.

Pour the foundation

Step 6: It is now time to prepare the concrete.

Step 7: Pour a 20cm (8") thick layer along the length of the foundations. Spread it out using a shovel.

Step 8: If the remesh frames are not long enough then slot two together in order to reach the desired length. Attach them together with annealed wire and immerse them in concrete.

Step 9 Fill the ditch to the top evenly.

Step 10: Using a masonry ruler, check and adjust the level if necessary.

Step 11: Finish by smoothing the concrete with a trowel. Leave it to dry for 2 or 3 days before continuing the construction.

If the wall which will be built is a concrete wall then lay the vertical chaining at intervals of 2 to 3 metres.

For retaining walls, the rebars should be further apart. The base will be wider on the side of which the ground slopes. This step will ensure that the wall is stable and is more resistant to the force exerted by the ground.

Continue this lesson by watching the second part "How to build a retaining wall: the wall."