What is the minimum height of a retaining wall?
In general, the top of the stem of any cast concrete retaining wall should not be less than 12 inches for the proper placement of concrete. Concrete retaining wall footing size The depth to the bottom of the base slab should be kept at a minimum of two feet.
How thick should a cast concrete retaining wall be?
This can add several inches to the thickness of the wall and varies depending on the severity of the exposure, soil type and reactivity, and so on. For proper concrete placement, the top of the stem of any cast concrete retaining wall should not be less than 12 inches.
How deep should footings be on a retaining wall?
Concrete retaining wall footing size The depth to the bottom of the base slab should be kept at a minimum of two feet. However, it should always be below the seasonal frost line, and that often is much deeper in northern climates.
How to build a retaining wall with concrete?
Excavate the trench where your footing will be poured. Pour and compact some gravel at the base of your footing. I generally use about an inch or two. Install steel rebar. Pour the concrete. When you’re building a retaining wall it’s important to make them sturdy. A retaining wall is used to stop soil from sliding down to a lower area.
How thick should a poured concrete retaining wall be?
7 1/2 inch thickness is sufficient for concrete retaining walls without or with minimal reinforcement. 8 feet or less in height and no more than 4 feet in height between the interior floor level and the finished grade on the outside wall are required.
How wide should a concrete wall be?
A typical foundation wall minimum thickness of eight inches applies to walls eight feet or less with no more than seven feet of soil pressing against it. Foundation walls taller than eight feet with more than seven feet of soil pressing against it requires a larger foundation wall 10 to 12 inches in width.
Do I need rebar in a retaining wall?
As water accumulates behind the wall, it percolates through the gravel into the drainpipe, which carries it off safely. 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.
How wide should a retaining wall footing be?
Footing Width Concrete footings should be wider than your retaining wall. For a 12″ wide concrete retaining wall, I usually pour a 2 foot wide footing for a wall no more than 3 foot high.
Does a 2 foot retaining wall need drainage?
If your retaining wall needs a drainage pipe, make sure the pipe has slots on all sides, not just one. A drainage pipe might be needed if: The retaining wall is at least four feet high or taller. Clay or other poor draining soils are behind the wall.
How do you size a retaining wall?
Multiply the length of the wall (in feet) by the height of wall (also in feet) to get the square footage of the outside face of the wall. Then, multiply 1.12. This allows for having 12% of the wall's height under the surface of the ground to give the wall more stability.
Can you pour concrete directly on dirt?
Long story short, yes you can pour concrete over dirt.
How deep should the footing be for a retaining wall?
The general rule of thumb is to bury about one-eighth of the height of the wall. For example, if your wall will be three feet (36 inches) tall, the first course of blocks should start five inches below soil level. The gravel base should start three inches below this.
Will concrete crack without rebar?
Without rebar reinforcement, concrete is highly prone to cracks due to tension forces. Rebar helps prevent cracks from growing wider largely by preventing cracked slabs from moving apart.
What is the standard footing size?
Under every house is a foundation, and under most foundations are footings. Most of the time we take footings for granted, and usually we can: For typical soils, a common 16- or 20-inch-wide footing can more than handle the relatively light weight of an ordinary house.
How thick should a concrete exterior wall be?
8" thickThe nominal width of blocks for exterior walls and load bearing interior walls should be a minimum of 6 inches and the face shell a minimum thickness of 1". It is better to construct exterior walls of 8" thick concrete block.
How wide is a standard wall?
Average Wall Width of Interior Walls Most interior walls are constructed with 2-by-4 framing, and each 2-by-4 has a nominal width of 3 1/2 inches. Drywall typically covers both sides, and it's usually 1/2 inch thick, which makes the wall 4 1/2 inches thick.
How thick are concrete home walls?
8 inchesStandard ICF external walls need six inches of concrete. However, areas susceptible to high winds require concrete thickness of at least 8 inches.
How thick is an interior concrete wall?
Solid precast concrete walls should have a typical thickness of 4-12 inches. Thin-shell walls should be 5-12 inches thick, including 1-4 inches of insulation. Sandwich precast concrete walls should also be 5-12 inches thick, including the 1-4 inch insulation.
How high should a retaining wall be?
In general, the top of the stem of any cast concrete retaining wall should not be less than 12 inches for the proper placement of concrete.
Why is proportioning important in retaining walls?
Proper proportioning of a retaining wall is just as important to its construction as its structural design. Construction-friendly proportions facilitate proper concrete placement and provide sufficient room for structural reinforcement.
Why should weepholes be spaced between walls?
Adequate spacing between weepholes allows uniform drainage from behind the wall. Weepholes should always have some kind of filter material between the wall and the backfill to prevent fines migration, weephole clogging, and loss of backfill and caving.
What are the failures of retaining walls?
One of the most common and telling failures of retaining walls is the inevitable tilting, cracking and bowing of brick, timber and concrete block retaining walls built by homeowners, well-meaning builders, and landscapers. These "problems" truly are failures, since the wall has not performed the task it was built to do, and that is to hold back the soil.
What is a construction joint?
Construction Joints: These are vertical or horizontal joints that are used between two successive pours of concrete. Keys are used to increase the shear resistance at the joint. If keys are not used, the surface of the first pour is cleaned and roughened before the next placement of concrete.
How deep are contraction joints?
Contraction joints are usually about 0.25 inches wide and about 1/2 to 3/4 inch deep, and are provided at intervals of not exceeding 30 feet. Expansion Joints: Vertical expansion joints are incorporated into the wall to account for expansion due to temperature changes.
How much of a wall is the base slab?
The length of the base slab is usually about 50% to 70% of the total height of the wall (bottom of base to top of stem).
How high is a concrete retaining wall?
A concrete retaining wall is 12 feet high and we have to park cars against it at the top. How wide should we make the footing of the wall?
What is the strongest retaining wall?
In general the strongest retaining walls are made from pile driven interlocked steel I beams and steel sheets. Next in durability is reinforced concrete. Both of these are costly and are usually only affordable by successful business or government.
What is a return wall?
Return wall is provided at the end of a culvert perpendicular to the culvert direction to ensure that water which comes with a high velocity is returned back to the stream or river so that it won’t affect the banks near the culvert. A retaining wall is any wall made of stone masonry , concrete etc to withstand the lateral pressure exerted by earth, water or any other liquid which it holds without breaking.
Why is my retaining wall failing?
It's one thing to build the wall, your biggest challenge comes from draining the fluid build up. Fluid retention is the number 1 cause of retaining wall failure.
What does vertical cracks mean on retaining walls?
The vertical cracks also indicate that there could be a settlement of the founding stratum along a part of the length of the wall.
How long are interlocking masonry blocks good for?
Stacked and pinned together railroad ties are usually good for about 30 years. Pressure treated lumber usually good for less than 10 years.
Which type of masonry block is the most durable?
For homeowners, stacked interlocking masonry blocks are most durable, but also very labor intensiv
How wide should a house footing be?
As you can see, heavy houses on weak soil need footings 2 feet wide or more. But the lightest buildings on the strongest soil require footings as narrow as 7 or 8 inches.
How does soil bearing capacity relate to the size of footings?
So, how does soil bearing capacity relate to the size of footings? The footing transmits the load into the soil. The lower the bearing capacity of the soil, the wider the footing needs to be. If the soil is very strong, the footing isn't even strictly necessary just the soil under the wall would be enough to hold the building up.
How much does a 12 inch footing weigh?
A 12-inch footing is 1 square foot of area per lineal foot, so the code is saying that the portion of a two-story wood house that bears on the outside walls weighs about 2,500 pounds maybe a little conservative, but reasonable.
Do masons need footings?
Regardless of bearing requirements, masons and poured-wall contractors want footings for their block or their forms to sit on. But the lesson to take is that when soils are very strong, (4,000-psf capacity or better), the footings may not be strictly necessary from the standpoint of bearing.
How deep should a retaining wall be?
The exact depth of the trench depends on the proposed height of the wall, but follow this rule of thumb: Dig a trench to be an eighth of the wall plus three inches. For example, if you want the finished height of your retaining wall to be three feet (36 inches) tall, you’d need to dig the trench eight inches deep to accommodate three inches ...
How much soil pressure does a retaining wall need?
Soil is heavy, especially when soaking wet from a recent rainstorm, so a basic retaining wall (four feet tall and 15 feet long) potentially has to support up to 20 tons of soil pressure.
What does a perforated drain pipe do?
The perforated pipe will carry groundwater to each end of the wall where it can drain harmlessly away. The ends of the drainpipe should then exit on each end of the wall, and you may cover them with crushed stone to camouflage their appearance. RELATED: The 10 Best Things You Can Do for Your Soil.
What happens when a retaining wall saturates?
When it saturates clay-type soils, they swell and put excessive pressure on the backside of the wall. To avoid failure, make drainage provisions at the same time as you go about building the retaining wall.
What materials are used to build retaining walls?
Retaining walls can be constructed using a variety of materials, from poured concrete and large timbers to natural stones, even bricks. For DIY purposes, opt for manufactured blocks that are designed specifically for building retaining walls; a locking flange along the bottom edge creates a secure attachment between rows.
Can you build a retaining wall short?
Shorter retaining walls, however, can be constructed by enthusiastic do-it-yourself ers equipped with some basic construction knowledge. Does that sound like you? If you’re looking to get your hands dirty and enhance your landscape with a retaining wall, these guidelines for building a retaining wall will help you get off to a good start.
