You can slope soil at a maximum of about 35 degrees, if it is mostly granular soil. Any steeper and you need a retaining wall of some sort to keep the soil in place.


Should you glue retaining wall blocks? Seasonal movement can be substantial. At 6 blocks tall, I would not recommend masonry adhesive. Adhesive is fine for caps or just a couple of courses, but six interlocking courses should have mortar and possibly vertical re-bar if you want it to last more than a season or two.

is a retaining wall necessary?

You need a way to control downhill erosion. If mountains of erosion materials are clogging important areas on your property, adding a retaining wall is a wonderful idea. Retaining walls minimize erosion by decreasing the angle of a slope and holding back soil. Erosion can threaten your home's foundation.

Will a retaining wall help a water problem? Retaining walls can help divert water away from foundations during flooding. Often they are just a part of a water flow management solution. Combined with proper guttering, French drains and foundation swales, most water can be diverted away from the foundation and home.

what is a retaining wall used for?

A retaining wall is a structure that holds or retains soil behind it. There are many types of materials that can be used to create retaining walls like concrete blocks, poured concrete, treated timbers, rocks or boulders. Some are easy to use, others have a shorter life span, but all can retain soil.

How do you tell if a retaining wall is failing? The 3 most common signs are the leaning, cracking and bulging of the retaining wall or its segments. Any of these things could (and likely) mean that the retaining wall is losing its fight to hold the soil back. Do not disregard these signs lest the wall fail at a crucial moment – say, in the middle of a rainstorm.

does a retaining wall need a footer?

A concrete footing serves as the foundation of many construction projects. If you plan to use brick, cinder block or stone that will include the use of mortar, then a concrete footing is recommended. If you are building a segmental retaining wall, then you will not need a footing.

At what height do you need a retaining wall? between 3 and 4 feet

Do small retaining walls need drainage?

Small walls under 3 feet in height may not require drain holes if the wall itself is not completely impermeable. For example, "dry-stacked" stone walls -- meaning those that are not held together with mortar -- have enough space between each stone to function as informal weep holes.

Do I need a permit to replace a retaining wall? A permit is required to install any type of fence or retaining wall over 30" in height. EXCEPTION: When an existing fence that was INSTALLED WITH A BUILDING PERMIT is being replaced with the same kind of fence in the same location at the same height, no permit is required.

Can you use cinder blocks for a retaining wall?

A cinder block retaining wall is only as straight and solid as the base it's built on. tall wall, excavate a trench deep enough to accommodate 4 to 6 in. of compacted base, 1 in. of leveling sand and half the height of the first course of blocks.

At what height does a retaining wall need to be engineered?

A permit commonly is required for retaining walls over 4 feet tall, whether they're stacked stone, concrete blocks or other material. The height measurement includes the base, which may be buried 6 to 12 inches or more under the soil.

What do you use to backfill a retaining wall?

Backfill refers to the dirt behind the wall. 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.

Do you need landscape fabric behind retaining wall?

Poor drainage resulting in saturated soil and frost heaving is the main cause of failure. That's why all good retaining walls begin with landscape fabric, backfill, and 4-inch perforated drainpipe. The depth you need to excavate depends on frost depth as well as the wall and soil type.

How do you prepare the ground for a retaining wall block?

How to Build a Retaining Wall With Blocks 01 of 12. Prepare Site for Blocks by Flattening and Leveling Ground. Lay Sand or Gravel as Base for Retaining Wall. Lay First Block of Retaining Wall. Maintain Level of Each Block and Between Blocks. Lay Block in Staggered Fashion for Stability. Check Level With Each Course. Prepare to Cut Block by Setting Chisel in Groove.

How deep should a retaining wall footer be?

What to do: Walls should rest on 3/4-minus or bank-run gravel, with the footer or wall base buried beneath the frost line (6 to 48 inches, depending on region). For deep frost, use concrete block rather than retaining wall to ground level, then build the retaining wall on that.

How thick should a footer be for a retaining wall?

Width (horizontal thickness): Your concrete footing should be a little wider than your mortared stone wall. If your wall will be 18 inches thick, you should make your concrete footing 24 inches thick.

How do you build a retaining wall on a steep hill?

How to Build a Retaining Wall on a Steep Hill Insert wood stakes to mark the boundaries of the first retaining wall at the base of the slope. Dig out vegetation and dirt from the base of the slope with a flat shovel and pile it in a nearby tarp. Dig out a trench at the base of the drop.