2019 Retaining Wall Cost | Concrete, Stone, Wood & Block Prices

Retaining Wall Cost

An average brick retaining wall that is 30 feet long and 4 feet high, without any built-in steps or extra reinforcements, is typically around $4,220. The average homeowner will pay $35 per square foot and spend between $2,450 and $6,650 to build a retaining wall.

A retaining wall holds back soil in order to prevent any changes to its structure. Without the wall, the soil could erode or slide. A retaining wall can also:

The average homeowner will pay $35/sq. ft. to build a retaining wall.

When it comes to building your retaining wall and choosing your preferred building materials, you have multiple options. The taller the wall, the more money youll have to invest in its foundation. Usually a wall above 4 will require engineering. Costs below are for wall material alone. On average you can multiply the material cost by 5 to get the installed price.

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Pros - Cinder block is lighter than concrete and made of stone or sand aggregate and coal cinders. Its very strong; durable; low maintenance; quick to install; impervious to rot, insects and fire; and its versatility allows for it to be used to build curved structures.

Cons - Cinder block is laid in trenches and not secured into the ground. For safety and stability reasons, they should not be used to erect a wall structure higher than 4 feet tall. Because of the bare-bones appearance of cinder block, the wall will still need some form of visual enhancementwith a stucco or veneer finish on the exposed surfaces.

Modular Or interlocking concrete blocks - $6$9/sq. ft. Retaining Wall Caps - $440$640 pallet or $54 to $69/face ft.

Pros - Modular concrete blocks like Versa-Lok are designed to connect together in a way not dissimilar to toy bricks. They are available in a wider range of sizes, color choices, and finishes, with a natural stone look, and they can be built into curves. Their locking mechanisms sometimes employ the use of pins, giving the resulting wall more structural integrity and the ability to go higher.

Cons Coatings on block walls can crack in freeze-thaw cycles. Without footings, youre limited to a wall under 4 tall.

Pros - Does not need a finish added in every installation. Color can be added to the mix before pouring into molds. Concrete stamping can make the walls look like natural stone for a lower upfront cost than a retaining wall made from natural stone. Structurally sound for high walls.

Cons They can crack in freeze-thaw cycles, and its difficult to align them perfectly when building unless you use the right form, which can take a long time to build.

Pros - A natural look in garden settings. Can be stained to match the yards tree colors. Wood is a material that is in ready supply and probably the most affordable retaining wall material. Can be built up to 4 tall or 56 with treated railroad ties and/or reinforcing steel rods. Pressure-treated Douglas fir is the best wood for avoiding rot. Quite easy to install.

Cons - Will require maintenance to get the longest life out of it, since it is prone to damage from water and pests like termites. The soil pressure behind it and rot will eventually cause it to fail, but you can slow the process down by placing waterproof sheeting between the soil and the wood fence. With adequate drainage and effective wood treatment, along with the right ongoing pest control treatments, the life of your wood retainer wall can only reach past 20 years, in most cases.

Pros - Stone veneeror faux stone, as it is also knowncan be applied to a range of wall structures for a more attractive finish. Typically available in thicknesses around of an inch, real stone is cut from larger slabs. Manufactured stone products are made in molds with added color dyes and surface finishes to complete the look of natural stone. Surface resistant to rot and pests. These can be added to a strong core.

Cons Design should be done by a professional or it can look out of place. Might not do well in freeze-thaw conditions without deep footings.

Pros - Expected to last 100 years or longer. Often only requires minimal onsite adjustments to stack properly. Brings a natural look to your wall, and you can reinforce a drywall look by only mortaring the back half of the stone blocks. Raise planting beds behind the wall for faster root drainage.

Cons - Homeowner may elect to drywallstagger the boulder sizes to take a departure from a more planned lookalthough finding/hiring someone to do this could be a challenge and it will be costlier. Transportation and onsite placement can be costly due to their weight. Drainage and water flow control strategy required.

Pros A unique look of a rock- or glass-filled cage. Does not require any type of professional installation. A great way to recycle unwanted wall materials like chunks of old concrete.

Cons Sedimentation. Not great in small spaces because of the need for a wide base. Wire casket might rust. The price of $20$352 is for the gabion basket, and support posts are also required.

Pros - Gives a warm, inviting, and structured garden feel. Constructed from readily available clay and shale, brick is very durable and drains well. It either makes up the whole wall enclosing an inner space of grout or concrete (cavity wall), or its built around a solid core or CMU block (block core wall) with whole, half, or thin brick.

Cons - The range of available colors is limited. Due to its weight and soil conditions in the installation location, extra precautions may be required in the construction of the foundation.

Pros - A popular choice for many designers. An alloy with copper and chromium in the steel, this composition leads to the development of a rusted mix of red, brown, and orange after a few years of exposure. No need for any future painting or maintenance. Can hold back earth without any great thickness of steel. Performs well in a completely vertical installation.

Cons - Not recommended for walls more than 4 or 5 feet tall.

Pros - Involves ramming earth into a form to give it structure and boosting it with internal rebar, wood, or even bamboo. Damp materials including silt, gravel, sand, and clay are poured into wood forms and are then tamped down in layers until wall is complete. Carving or mold impressions are often done once formed. Another method is to build rammed earth blocks into a wall.

Cons - Labor is the significant cost factor for rammed earth because of the time it takes to produce the finished product onsite. Premanufactured rammed earth blocks are less expensive because the work has already been done, and they just need to be stacked onsite.

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Particular types of walls require a particular type of installation, with some needing an engineers help.

The most popular option, railroad ties (these look like fence posts) dont require the use of a lot of tools or additional materials. An easy and affordable installation. They are treated to prevent breakdown, but the chemicals used can seep into surrounding soil so they are not recommended for food gardens. Many homeowners are capable of completing the project as a DIY project.

Requires a bigger range of tools and experience to install. Interlocking blocks help to create a straight and stable wall. It is not prone to rot or decay and wont require much maintenance.

Criblock is a type of gravity retaining wall that constructs cells from materials like plastic frames, precast concrete, or timber. It lacks steel reinforcement. The cell structure is designed to facilitate drainage through wall openings so as to ease hydrostatic pressure behind the wall. The drainage outlets can be conveniently placed over built-in flower or vegetable beds.

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For this work, your contractors hourly rate will vary depending on the level of difficulty involved in the work. Prices below are for independent workers rather than contracting firm prices, which can be double.

You can usually get a better price bid on projects during the winter months when contractors are not as busy. Also, wall material sellers give larger discounts in the late fall/winter season.

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A very simple way of estimating your wall installation cost is to multiply the cost of your wall material by 5, although this brings you only to a starting point in price. Essentially, your wall will consist of two main measurements to make your estimationthe width and the height of the wall.

A good rule of thumb is to add around 10 % to the number for the height of the wall. That is to accommodate installing at least 10 % of the wall below the surface to add more stability to the structure.

If the top row is to be completed using a different block, then you just need the number of columns since there is only one row.

To add a buffer for error, bad blocks, and any damage from accidents on site, it might be prudent to add another 10 % to the total number being ordered. If not used, they can be left onsite for any repairs or returned to the vendor.

Wall width x at least 6 (for the depth into the ground) x wall depth = gravel needed.

Some installers prefer to mix sand and gravel, and the average cost is $4$6 per 0.5 cubic foot bag. Sand is around $4.50 for 50lbs

Depending on the typical climate for your location, your retaining wall should have around 12 of gravel right behind the entire width and height of your wall to facilitate proper drainage. Multiply the width and height of your retaining wall by 12 to give the total cubic feet of backfill gravel that will need to be ordered. $4$6 per 0.5 cubic foot bag

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There are a wide variety of factors that will influence the cost of replacing an existing retaining wall including the following:

Each possible type of work is followed by average price:

Before any retaining wall is replaced, it may be necessary to hire a Geotech engineer to come and take soil samples, and even drill cores to get down to the bedrock for samples. Extra cost may be incurred if any power, water, or gas lines were installed in the earth being held back by the current wall.

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Repairing a retaining wall can cost as much as replacing the wall would, depending on the reason for the repair. Replacing a few bricks could cost in the region of $200, but if your wall has poor construction or has shifted, then repairing it can cost a lot more.

DIY or low-quality construction

Wall fails

Load exceeds design

Full or partial destruction

Inadequate drainage

Wall bulging

Inadequate footing implemented

Failure or signs of future failure

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Of each type of retaining wall, there will be a range of installation costs because some are simple while others require engineering and the use of more expensive materials.

This type of retaining wall is much thicker and leverages its extreme weight. Its also designed to take advantage of geometry to perform its task. Concrete gravity walls can be used for installations requiring a wall of up to 9 feet tall, and should be between 50 % 60 % the thickness of the wall height.

For extra strength, reinforced masonry and reinforced concrete walls are spread on foundations and are held firm because of their weight and the internal reinforcement bars.

Built using soil reinforcements or geotextiles that are laid in layers within a precise granular fill. Under certain conditions, these are used instead of reinforced concrete as a cost measure, or because the conditions on site necessitate their use, or as an improvement to an existing installation.

Anchored earth, gabion, tailed gabion

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Retaining walls can protect a building foundation and stop it from shifting or falling when there is a steep incline in your yard space. They can also improve irrigation to landscaping on higher slopes. They can add attractive design features to your landscaping, adding some punctuation around flowerbeds and allowing for certain areas to be featured.

Before you build a retaining wall, youll more than likely need to hire an engineer, due to the complexities that can arise from the local soil properties, pressure, and gravity. A smaller wall in a garden can be straightforward enough for your contractor, but taller walls of the same design offer less support, and any one of a range of different designs or materials may be more suitable. Over time gravity combined with enough rainfall and an inadequate drainage system could contribute to the failure of the wall and the collapse of the soil behind it.

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Even building a small wall thats under 2 feet tall without the right equipment is time consuming. You have to dig a horizontal trench, and its also difficult to get it level. Without having an analysis done on the soil and understanding drainage and the impact on the future wall from any nearby structures, you could easily be constructing the wrong type of retaining wall. Because of potential complications from building the wrong foundation, to all the science and engineering that goes into the construction of an effective and safe retaining wall, it is something best left to professionals, especially if you plan on building a high wall.

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There is a wide range of different possible solutions for a retaining wall, but below are the fundamental elements to build a 3-foot-tall retaining wall using blocks and tops and a gravel base, on top of which you will lay the blocks.

Estimate how many blocks and cubic feet of gravel base to order for the foundation. Think about what to do with the dirt that will be removed, and if it will be used to compact the earth behind the wall. Make sure you have, or can get access to, a range of tools including a rake, shovel, spade, pick ax, bubble levels, hand tamper, rubber mallet, hammer and mason chisel, glue, stakes, and some twine.

Dig the trench for the foundation and also dig out the soil from where the retaining wall is going to be installed. For this example:

On the rear of where the wall is going, cut 6 back from where the rear of the bricks will be to allow a barrier of inch rough rock drain gravel to facilitate drainage. Also, the floor of the base trench should have a slope on it to prevent water pooling and saturating the ground under the base.

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Because of the severity of both legal and financial issues you could face in the event of a retaining wall failure, finding an experienced professional for your retaining wall is very important. Apart from the inconvenience, you may also find yourself with damage to your home or a neighbors home. Use the criteria below to look up specialists here on HomeGuide to create your shortlist of contractors to request bids from, and make your final selection from there. Add contractors to your list who have as many of the following characteristics as possible when creating your shortlist:

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2019 Retaining Wall Cost | Concrete, Stone, Wood & Block Prices