QA

Question: How To Build A Retaining Wall With Concrete 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 deep should footings be for a concrete block wall?

Normally a foundation wall with seven rows of blocks will be 24 inches wide and 12 inches deep and should have a footing 30 inches below grade. Remember to build a leveled footing where the cinder block will be placed.

What do you put under retaining wall blocks?

Use crushed gravel to fill in the back and sides of your blocks. Backfill helps with water drainage. Compact the backfill before starting on the next row of blocks.

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.

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.

Do you need rebar in a block wall?

Wall Size. A freestanding garden wall or block privacy fence will require less reinforcing than a basement or other load-bearing wall in a house or other building. An 8-foot-high wall will obviously require more rebar than a 4-foot wall. Very short walls, under 4 feet and laid with mortar, may not require any rebar.

Does a block wall need a footing?

All concrete block walls—both structural and non-structural—require a solid, poured concrete footing. Standard 8” x 8” x 16” blocks would require a 16” wide footing. Make sure the footing depth extends below the frost line, and check local building codes for construction requirements in your area.

How thick should a 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.

How high can I stack retaining wall blocks?

Three feet is the maximum recommended height of a stacked stone wall built on a clay surface. It is also the stable height of most stand-alone stone walls. Sandy soil doesn’t absorb water, making it ideal for building a retaining wall without reinforcement.

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.

How high can you build a concrete retaining wall?

* In New South Wales, you need permission from council to build a retaining wall higher than 600mm from ground level.

How many deadmans are needed for a retaining wall?

Install one dead man every 6 to 8 feet around the entire wall. Continue building up the retaining wall, using landscaping screws to secure each timber. Cover the ground in front of the retaining wall with 2 to 4 inches of bark mulch.

How deep should posts be for a retaining wall?

Retaining wall posts should be at least as deep as the amount of soil they will be holding. A good rule of thumb is to halve the height of the wall and then add 4 inches. This is how deep you should place your posts.

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.

How do you build a retaining wall step by step?

Follow these steps to properly install a retaining wall. Dig a level-bottomed trench wide enough for the base stones to fit into. Compact the bottom of the trench with a hand tamper. Lay landscape fabric in the trench. Start the wall’s second layer using a staggered pattern. Make sure the wall is level.

Do you fill cinder blocks with concrete?

Whenever you are working with cinder block, you can strengthen them significantly by filling them with concrete. Cinder blocks are less expensive to work with than poured concrete in home construction projects, but they are not as strong.

What is the difference between a cinder block and concrete block?

Cinder block is made of concrete and cinder. Concrete block is produced from steel, wood or cement. Cinder block is lighter than concrete blocks. Concrete block is heavier because it contains stone and sand.

What is the difference between brick and concrete block?

Brick—A solid or hollow manufactured masonry unit of either concrete, clay or stone. Concrete block—A hollow or solid concrete masonry unit. Larger in size than a concrete brick. Concrete brick—A concrete hollow or solid unit smaller in size than a concrete block.

How much sand and cement do I need for 100 blocks?

Averages. As a general rule, you can order around 600 to 800 pounds of sand for every 100 blocks you are setting, provided that you are using the standard size cinder block. You will use two and a half to three bags of cement mixed in with that sand.

Can you lay block on dirt?

Cinder blocks are sometimes set in cement but you can also place them directly into the soil. They are solid and heavy enough to hold down weeds and resist shifting.