QA

Question: How To Make Retaining Wall Blocks

What is the cheapest way to build a retaining wall?

What Is the Cheapest Type of Retaining Wall? The cheapest type of retaining wall is poured concrete. Prices start at $4.30 per square foot for poured concrete, $5.65 for interlocking concrete block, $6.15 for pressure-treated pine, and about $11 for stone.

How thick should a block retaining wall be?

Retaining walls can be tricky to build as they need to be strong enough to resist horizontal soil pressure where there are differing ground levels. One of the things you must get right is the thickness of the wall. It should be at least 215mm thick and bonded or made of two separate brick skins tied together.

Can you build your own retaining wall?

Choose a DIY-friendly building material. Retaining walls can be made from wood, bricks, natural stones or concrete blocks. For DIYers, it’s best to use concrete retaining wall blocks, which can be interlocking and are heavy enough to stay in place without cement or other adhesive.

Does a 2 foot retaining wall need drainage?

These walls need a drainage system regardless of the wall height. If there are poor draining soils such as clay behind the wall, there needs to be drainage incorporated the wall system. Clay when wet is very weak, so it is essential to provide a way for water to escape from behind the wall.

How deep and wide do footings need to be for a retaining wall?

Footings for Dry-Stacked Wall To construct a footing for a dry-stacked retaining wall, excavate a trench that is 5 to 7 inches deep plus 1 inch for every 8 inches of planned wall height.

What is the easiest retaining wall to build?

For the average do-it-yourselfer, building a retaining wall is easiest when using masonry blocks that will be stacked no taller than three feet, with no mortar binding the stones or concrete members.

What is a sleeper retaining wall?

One particular type of retaining wall is a sleeper retaining wall. These walls used wooden or concrete planks, usually built for use in railroad tracks (parts called sleepers since they simply lay in place and allow for trains to glide along them) to form the structure of the retaining wall.

How do you build a retaining sleeper wall?

Constructing a retaining wall out of upright sleepers is pretty straightforward. Simply dig a trench, lower the sleepers in vertically side by side, and then backfill with a dry concrete mix, that you can ram down around the railway sleepers untill the wall is rigid.

How high can a retaining wall be without council approval Qld?

Generally, you can build a retaining wall up to 1.0m high in Qld without needing to engage a structural Engineer or organise a development approval. Often manufacturers of retaining materials will specify the maximum height that products can be built to without engineering.

Can you use sand as a base for a retaining wall?

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. Be sure to use coarse builder’s sand, and tamp it down firmly to keep the sand from shifting and settling after the wall is built.

Do I need a concrete footing for a retaining wall?

A buried structural footing is usually required for larger retaining walls. To create this, a landscaper pours concrete below frost level (the depth to which the ground will freeze during the winter). Footings poured too shallow are prone to shifting and moving if moisture in the soil freezes and heaves.

Can you build a retaining wall on concrete?

While you can build a retaining wall on concrete, it isn’t that straightforward. If you have an existing concrete base, you cannot just build your wall on top of it. Without being secured into the concrete, your wall will slide due to the soil pressure against the wall.

Does a 4 foot retaining wall need drainage?

Any reinforced wall or walls over 4 ft. (1.2 m) in height or with slopes or other surcharges above the wall will need a toe drain. In all cases wall rock is located within the cores of the block and a minimum of 12 in. (300 mm) behind the block.

Do you need gravel behind retaining wall?

Second, a retaining wall must have properly compacted backfill. In order to provide proper drainage, at least 12 inches of granular backfill (gravel or a similar aggregate) should be installed directly behind the wall. Compacted native soil can be used to backfill the rest of the space behind the wall.

How thick is a concrete footing?

Minimum foundation wall is 6 inches for masonry or concrete construction. The minimum reinforced concrete footing thickness is 6 inches or 1 1/2 times the length of the footing projection from the foundation wall.

How much weight can a retaining wall hold?

Even small retaining walls have to contain enormous loads. A 4-foot-high, 15-foot-long wall could be holding back as much as 20 tons of saturated soil.

Can you put sleepers on soil?

For one, you can simply place your sleepers directly onto soil, allowing the heavy sleepers time to bed in. Simply dig a shallow trench and place your sleepers down onto your newly created gravel or sand-based foundation.

How do you anchor sleepers to the ground?

Cut your sleepers to your required length, which could be random for a rustic look. Then mix up some lean mortar, such as 6:1, to be used as a concrete base and haunching. Place at least a 50mm bed of concrete in the bottom of the trench and start inserting the sleepers, haunching them up as you go.

How high can a sleeper retaining wall be?

This system works for sleeper walls up to 1200mm in height; anything higher than 1200mm needs to be designed by an engineer to take account of local ground conditions and loadings.