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I have read plenty of articles from Forbes to DIY blogs that have an answer to this question. Even sites like Angi will provide pricing information. Is it truly accurate?

In my experience, not really. I think it sets pricing expectations without considering the exact conditions you might be facing at your home.

size of the wall

Square footage is generally how a wall is measured. We have to include at least one course of block that is buried for the footer. Was this considered by the writer of the article?

If a wall is at all over 4 foot in height, this automatically adds to the cost in terms of reinforcement for wall stability. This means more excavation into the slope, more aggregates needed behind the wall, and the use of geo grid to anchor the wall into the slope.

Materials used

The type of block that you might find at the big box stores isn’t suitable for a retaining wall. It is okay for a DIY a flower bed border. For a wall that will hold back a load of any kind, professional materials from a landscape supply yard are necessary.

Block that deviate from the typical standard Versa-Lok will generally cost a little more due to enhanced detail (more stylized or made to mimic the look of natural stone). These higher-cost block options usually don’t hold back as much as the typical Versa-Lok, so the reinforcement that I mentioned above would be necessary to create any wall taller than a standard 2′ garden wall.

Footer to Upper Courses Ratio

The preparation of the footer for the wall is more time consuming than setting the block for the upper courses. It’s the foundation that can make or break the rest of the installation. For a wall that is 100 feet long and 2 feet tall, the actually laying of block will take longer than a wall that is 50 feet long and 4 feet tall.

Access to the site

A retaining wall sitting along a driveway or across the front of a property makes for a quicker install than a project inside of a fenced in backyard. Not only is there more time in traveling back and forth to the backyard, but access is limited to within the fence gate or between fence posts if a panel can be temporarily moved. Without machine access, more labor is needed.

conclusion

There are a variety of factors that affect the cost of a retaining wall. Pricing isn’t a secret, however it can’t be reduced to a simple square foot number. I believe that the intention to help homeowners prepare for a project is great. What I don’t like is the disappointment that comes with unmet pricing expectations.

Quick vocabulary lesson on the key components of a retaining wall

Here are some of the key terms to use when speaking about a retaining wall:

Segmental Retaining Wall (SRW): This refers to any wall that consists of individual blocks rather than a wall that is a single structure (such as poured concrete).

Base: The foundation of the wall. Usually made up of well compacted 2A limestone. 6″ deep minimum

Base course: The first layer of block and the most time consuming to lay because it needs to be completely level. This block should be completely buried/underground.

Batter: The stepping back of a retaining wall into a slope. When looking at the wall from the side, the wall should not be completely vertical/stand straight up and down. The amount of batter depends on the block style, but this is usually around 1/2″ to 3/4″ for each course of block.

Drainage aggregate: The stone that sits behind a wall. Typically this is #57 or 2B angular limestone. (Rounded stone will not stay put). This should be at least 12″ deep from the back of the wall block into the slope.

Drainage pipe: Not a French drain, but rather a pipe that sits behind the wall (usually behind the second course of block so that it can outlet at or above ground level). This is a 4″ diameter pipe that can be either corrugated, perforated pipe or firm pipe/PVC with holes in it.

Impervious fill: This is what sits on top of the backfill when the wall is all done. It can be soil, mulch, stone or a combination of these materials. Along with the caps, this can finish off the wall and restore the lawn or landscaping post-construction.

My go-to visual for retaining wall construction is this cross-section from Versa-Lok:

I just dated myself with that title. Yes, I know it’s also pretty lame.

Usually perceived as a way to skirt regulations or cut costs, homeowners and contractors alike will turn to terracing as the solution for holding back large or steep slopes.

The Law of the Land

Let’s start with regulations. Any wall over 4 feet in height needs a stamped engineered drawing and a permit. I can’t speak for other states, but this holds true in Pennsylvania. I’ve seen walls that are 3-ish feet tall and immediately behind that wall will sit another wall about 2-ish feet tall. Math is math though. We still have 5 feet total height of heavy concrete block holding back the slope. Beyond violating building code, this is a dangerous situation. The bottom wall has to hold up the slope AND the weight of the upper wall. Something has to (and will) give.

In the above example, I’m assuming that neither of these walls was reinforced with geogrid (another topic for another blog post). Reinforcement is the only way that a terraced situation like that will stand the test of time. ‘Like that’ meaning the two walls are close together.

There is one other way to create terraced walls without reinforcement. You just have to have the space to make it happen. A good rule of thumb for spacing terraced walls sans geogrid reinforcement is this: take the height of the lower wall, multiply it by 2 and that is the number of feet that you must have between the upper wall and lower wall. This ensures that the upper wall is not adding extra force to the wall below. In the above example, if the bottom wall is 3 feet tall, then you would need to excavate back at least 6 feet into the slope before starting the upper wall.

Let’s Talk Dollars

On to the cost of terracing. Whether you reinforce both walls or use the handy rule of thumb from above, terracing generally costs more than creating a single taller wall. Even with good distance between the walls, there is a lot of dirt to be excavated. It also adds more linear feet of base course. The most time consuming portion of the wall is prepping base material and leveling the first course of block. Terracing takes double the time.

It’s Not All Negative

Terracing is a great way to add some visual interest to a slope. The space between the walls allows for some plantings to soften the landscape. It can also be a great way to open up a space that otherwise might feel closed off (think tall wall in a confined space). I don’t want you to think that I’m against terracing. I just want you to be in the know about the right way to do it!

The answer is yes and no.

In a normal circumstance, homeowner’s insurance will NOT cover the cost to replace your retaining wall. According to The Hartford Insurance, categories not typically covered include:

• Normal wear and tear
• Poor workmanship or defective materials
• Birds, vermin, rodents and insects

The article can be found here: https://www.thehartford.com/aarp/homeowners-insurance/what-does-homeowners-insurance-cover

So what is covered?

I’ve seen two instances where I have seen insurance step in. In the first claim a tree removal company lost control of a stump grinder and it damaged the homeowner’s wall. The second claim was the result of a vehicle crashing into a retaining wall.

The best approach is to be proactive when it comes to replacement.

Too many times homeowners trust a contractor only to find that their trust was misplaced. Sometimes they are fortunate enough to break ties with that contractor before much if any damage is done. The rest are left with a huge lesson, a matching price tag, and poorly executed work.

So how do you know who to choose?

I created a video that should provide a good starting point for vetting and ultimately hiring a contractor. Take a look:

Check out that face! What a great first impression.

Are you still left with questions? Please ask!

We’ve had a brief glimpse of the spring weather to come, but we’re back to winter again. For now at least, but not for long.

Spring is traditionally the time when most people think of home improvements. It only makes sense as spring brings a time of renewal and new life. It’s also the season that brings a host of new landscapers to the area. Every year it seems that there are more unfamiliar names driving around town. Other names are forgotten as they leave the industry for a new venture.

Did you know that landscaping is the second most failed industry (only second to restaurants)?