The construction of a retaining wall could seem a common day-off job, but in fact, it could be somewhere from average to challenging, up to hard. It may be as simple as a DIY task or as complicated as a construction. The complexity often relates to the height of the wall, soil type, materials used, and much more. So it depends on whether the construction has to withstand high weight or not.
For homeowners or small contractors considering this project, using On Time Estimating Services can be incredibly beneficial. These services help plan out material costs, labor, equipment rentals, and drainage solutions, ensuring the project stays within budget and avoids delays. This is especially important when the wall exceeds a few feet in height or must meet local building codes.
Small, decorative walls constructed with interlocking blocks often fall within the capability of skilled homeowners, but larger (or supporting) ones normally require special tools and drainage systems, in addition to the specialized skills of building professionals. Simply put, not every retaining wall is a straightforward task to construct and most of the time, it is more difficult than expected.
How To Build a Retaining Wall
The following is a step-by-step look at how to construct a simple retaining wall with interlocking concrete blocks:
Planning and Measuring
- Look into local building codes.
- Measure wall height, length, and layout.
- Mark and stake out the land.
Excavation
- Excavate a trench that is deep enough to accommodate the base- usually 6-12 inches below the ground surface level.
- The width is needed to accommodate block placement and backfill the gravel.
Base Preparation
- Crush gravel 4-6 inches and add to it.
- Make a solid foundation using a plate compactor.
First Placement Course
- Make the initial row of blocks thoughtfully.
- It is essential to make sure that all of them are leveled, both front/back and left/right.
Construction of the Wall
- Pile up the next rows in a dumpy way.
- Align each piece of the block using a rubber mallet.
- Fill it up with gravel and compact each mass of 6-12 inches.
Drainage Installation
- Install a drain pipe with holes on the footing behind the wall.
- Avoid clogging by using filter fabric.
- Ensure that water can drain downslope.
Topping the Wall
- Install capstones with concrete adhesives.
- Grading the soil behind the wall is to be completed.
These are simple steps, but in order to make the wall support the weight, pressure, and weather, each step should be done well.
Key Factors That Affect Difficulty
1. Wall Height & Load
The higher the wall, the more difficult it becomes to construct. Any wall more than 3 or 4 feet high generally needs:
- Engineering plans
- City permits
- Drainage design
- Concrete construction support
When you have heavy loads on your wall, such as a driveway or steep slope, then it is no longer a landscaping feature but a structural system that must withstand immense pressure. That complexity increases the difficulty level to a great extent.
2. Material Type
Certain materials are readily worked with as compared to others:
- Most DIY-friendly are concrete blocks (such as interlocking retaining wall blocks). They can be easily stacked and most of them include an embedded lip to align.
- Natural stone is more beautiful, and more skill is needed in cutting, leveling, and matching.
- Cast concrete can be very strong and needs forms, mixing, and curing.
- Wood can be installed easily yet is less durable and it can rot with time.
- Gabion walls are heavy and time-consuming, yet efficient and they can be aesthetically powerful.
3. Soil Conditions
The soil in your yard makes a tremendous difference. Loose soils or sandy soils can be shifted easily and would require a firm reinforcement. Heavy-clay soils are water-retentive and heighten hydrostatic pressure on the downstream side of the wall. It becomes difficult to excavate the land and to design drainage due to poor soil conditions.
4. Drainage Requirements
The most common cause of retaining walls failure is poor drainage. When water accumulates behind the wall (Hydrostatic pressure), it can force over the structure, or even collapse down.
Adequate drainage systems consist of:
- Drain pipes (French drains)
- Gravel backfill
- Weep holes
- Geotextile fabric
Improper design and installation of such features are complex and expensive to do, although the alternatives can be perilous, resulting in structural collapse.
5. Site Accessibility
Will you be able to bring equipment, or will everything be by hand? Is the location sloping, rocky, or covered by tree roots? Digging, leveling, and transportation of materials over tight or awkward are made hard.
DIY vs Hiring a Professional
There are some pros and cons in case you plan to construct a retaining wall yourself:
DIY Advantages:
- Cost savings: You save on labor expenses.
- Satisfaction: The accomplishment of a wall can become a satisfying experience.
- Design control: You get to develop at your own time and to your specifications.
DIY Challenges:
- Labor-intensive: Digging trenches, lifting blocks, and grading soil are hard physical jobs.
- Tool requirements: Shovels, levels, compactors, and potentially saws or other power equipment.
- Knowledge gap: Misguided construction methods will lead to the fall of the wall.
When to Call a Professional:
- The height of the wall is greater than 3-4 feet.
- The wall carries the weight of buildings.
- The land is sloppy or poorly drained.
- You desire quality material such as stone or poured concrete.
Professionals contribute their knowledge in the grading of soil, compaction, drainage system design, and permitting to make sure that your wall is safe, stable, and will last long.
Common Mistakes That Make It Harder
It is worth noting that even skilled DIYers can get things wrong and fail:
Avoiding compaction: Loose soil under the base may lead to settling.
Lack of proper drainage causes water accumulation and collapse of walls.
Incorrect materials: Garden bricks instead of retaining wall blocks.
No failure: Negotiating the wall back into the slope.
Neglecting the frost lines: The water around very cold areas may freeze beneath the wall and cause the wall to move.
Such mistakes would not only complicate the job, but they might necessitate building and demolishing the wall; this consumes time and money.
Conclusion: So, How Hard Is It?
A small decorative retaining wall of less than 3 feet of interlocking block can be a somewhat challenging DIY job that can be made easier by being relatively skilled with your hands, not being in a rush, and paying attention to instructions.
Otherwise, anything over half the height, structurally supporting, and that is on hard terrain, is a construction task, and it can best be left to professionals. This challenge increases with wall area, drainage complexity, soil type, and structural stability requirements.
If you are not sure of the design or structural requirements, hire a contractor or engineer, and one suggestion before you break ground consider investing in pre-construction estimator services to assist in budgeting and planning.
FAQs
How long does it take to build a retaining wall?
A small do-it-yourself wall can be built in just a weekend or two. Depending on the size and the site conditions, professional projects can require 1- 3 weeks.
Do I need a permit to build a retaining wall?
Yes, walls taller than 3-4 feet most likely need a permit. Contact your local building department to see what they require before you begin.