QA

Quick Answer: How To Pour A Concrete Retaining Wall

How thick does a concrete retaining wall need to be?

Base width = 1/2 to 1/3 of the height of the wall. Base thickness = 1/8 of the height of the wall but not less than 12 inches. Stem thickness = 6 inches + ¼ inch for each foot of wall height.

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.

How deep should footings be for a retaining wall?

All footings should be a minimum of 150mm (6″) in depth, with the bottom 350 – 400mm (14-16″) below ground level on most soils. For clay soil however, thicker and deeper footings should be used.

Can you make a retaining wall out of concrete?

Poured concrete retaining walls can be colored, textured, accented with embedded objects and much more. When installed properly, concrete offers much more room for customization than any other retaining wall material. If the wall exceeds four feet in height, footings should be poured separately. Allow concrete to cure.

How do you rebar a concrete wall?

Rebar Placement in Walls Rebar is placed horizontally and vertically in the wall, in a grid pattern. As a minimum, #4 rebar (1/2 inch) is spaced vertically at 36 inches on center, continued to within 8 inches of the top of the wall, placed on the tension side — the inside face — of the wall.

Are poured concrete walls cheaper than block?

Is a poured concrete foundation cheaper than a block wall foundation? Usually, the cost of construction varies from place to place. But as a matter of fact, poured walls cost about 20% less than the block foundation walls.

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.

Do I need rebar in a retaining wall?

A retaining wall must provide a way to release the water that builds up in the slope behind it. Retaining walls must be stronger than freestanding walls. Insert rebar in the footing when you pour it; this should be done at every three blocks or at intervals specified by your local codes.

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.

How thick should concrete footings be?

Eight inches is the minimum thickness for a footing. Ten inches is better and twelve inches is highly desirable. The depth of the footing in the ground depends on: the local frost depth.

How thick does a concrete foundation need to be?

For masonry or concrete construction, the minimum foundation wall will be 6 inches. The minimum reinforced concrete footing thickness will be 6 inches or 1-1/2 times the length of the footing projection from the foundation wall, whichever is greater.

How do you build a base for a retaining wall?

Lay the Base Due to soil erosion, your retaining wall should be built on a solid foundation made from gravel. Choose gravel that has stones sized between 1/2-inch and 3/4-inch. Fill the trench with a 2- to 3-inch layer of gravel. Use a rake to ensure the stones are evenly distributed.

Are poured concrete walls better than block?

Poured concrete wall foundations are arguably stronger than cinder blocks. Poured walls have a better lateral strength, which means they are able to resist more pressure from the water and the soil from the outside. Poured walls tend to be the preferred choice of new construction builders.

How far apart is rebar in concrete?

Place rebar in a grid pattern with a spacing between bars of approximately 12 inches. In either case, blocks should be used under the reinforcement to keep centered within the concrete. Synthetic fibers have also proven to be beneficial in driveways as a way to reduce shrinkage cracks.

How far should rebar be from concrete?

Reinforcement should also be placed low enough so saw cutting does not cut the reinforcement. For welded wire reinforcement, the Wire Reinforcement Institute recommends steel placement 2 inches below the surface or within the upper third of the slab thickness, whichever is closer to the surface.

In what way is concrete different from grout or mortar?

Basically concrete is stronger and more durable so it can be used for structural projects such as setting posts whereas mortar is used as a bonding agent for bricks, stones, etc. Concrete is a mixture of water, cement, sand just like mortar.

How do you waterproof a poured concrete wall?

Waterproofing a Basement with a Poured Concrete Foundation This can be prevented, or stopped, by applying an exterior waterproofing membrane to the foundation wall. The membrane consists of asphalt-modified polyurethane and is applied thickly to the wall surface with a trowel to form a permanent water barrier.

Are cinder block walls filled with concrete?

The concrete blocks that are used to build block foundations are hollow. After the concrete blocks are laid, the voids can be filled with a cement-based mortar or poured concrete that contains small pea gravel. If the builder does this, the filled concrete block walls become nearly identical to poured concrete walls.

WHY DO Retaining walls fail?

There are many causes of a failing retaining wall: Lack of site investigation: Soil compression, backfill materials, water tables, landslides and building codes restricting soil bearing capacity should all be thoroughly investigated to reduce the probability of retaining wall failure.

How far apart should posts be for a retaining wall?

Retaining wall posts should be at least three feet apart. The distance can be slightly longer or shorter if it works better with your measurements. However, you shouldn’t go more than seven feet apart to make sure your wall is sturdy enough.