Cheapest Way to Make a Retaining Wall in Construction – Complete Guide

Retaining walls are essential structures in construction for holding back soil, preventing erosion, and creating level spaces in sloped areas. While they can be expensive, there are several cost-effective methods to build a durable retaining wall without compromising strength and stability.

This guide explains the cheapest retaining wall options, cost factors, and money-saving tips so you can build one on a budget.

Average Cost of a Retaining Wall

The cost of a retaining wall varies depending on materials, size, and labor. On average:

• Low-Cost Options: $10 – $20 per square foot
• Mid-Range Options: $20 – $35 per square foot
• High-End Options: $35 – $60+ per square foot

For budget-conscious projects, focusing on affordable materials and DIY-friendly methods is key.

Cheapest Retaining Wall Materials

1. Timber (Treated Wood)

• Cost: $10 – $15 per sq. ft.
• Pros: Affordable, easy to install, DIY-friendly.
• Cons: Shorter lifespan (15–20 years), susceptible to rot if not properly treated.

2. Concrete Blocks (CMU Blocks)

• Cost: $12 – $18 per sq. ft.
• Pros: Durable, widely available, simple to stack.
• Cons: Requires leveling and compact base for stability.

3. Gabion Walls (Wire Baskets Filled with Rocks)

• Cost: $15 – $25 per sq. ft.
• Pros: Strong, permeable, minimal maintenance.
• Cons: Industrial look may not suit all aesthetics.

4. Dry-Stack Stone

• Cost: $15 – $20 per sq. ft. (if locally sourced)
• Pros: Rustic appearance, no mortar required.
• Cons: Time-consuming to assemble.

5. Recycled Materials (Old Bricks, Scrap Wood, Rubble)

• Cost: $5 – $10 per sq. ft. (if sourced for free or cheap)
• Pros: Eco-friendly, very low cost.
• Cons: Irregular sizes make installation harder.

Cost Comparison Table

Tips to Save Money on a Retaining Wall

1. DIY the project – Labor is often 40–50% of the cost.
2. Source free or discounted materials – Check local construction sites, salvage yards, or online marketplaces.
3. Build a shorter wall – Reducing height lowers both material and labor expenses.
4. Use gravity walls – Relying on weight instead of reinforcement can cut costs for small walls.
5. Avoid complex designs – Straight walls are cheaper than curves or terraces.

Step-by-Step – Cheapest DIY Retaining Wall (Using Timber)

1. Plan & Measure – Decide wall length, height, and location.
2. Excavate – Dig a trench for the base, ensuring a level foundation.
3. Add Base Material – Use compacted gravel for stability.
4. Place Timber & Secure – Stack treated wood horizontally, securing with spikes or rebar.
5. Backfill & Drain – Fill with gravel behind the wall for drainage, then add soil.

Conclusion

The cheapest way to make a retaining wall in construction often involves using treated timber, concrete blocks, or recycled materials. By sourcing materials affordably, keeping the design simple, and doing the work yourself, you can significantly cut costs while still building a functional, attractive wall. Always ensure proper drainage and foundation to maximize the wall’s lifespan, even if you’re working on a tight budget.

FAQs – Cheapest Retaining Wall in Construction

Q1: What is the absolute cheapest retaining wall material?
Recycled materials such as old bricks, pallets, or scrap wood can cost as little as $5 per sq. ft. if sourced for free.

Q2: How long will a timber retaining wall last?
With proper treatment and drainage, timber walls can last 15–20 years.

Q3: Do I need drainage behind a cheap retaining wall?
Yes, drainage prevents water pressure buildup, which can cause the wall to fail regardless of cost.

Q4: Can I build a retaining wall without concrete?
Yes, dry-stack stone, timber, and gabion walls can be built without concrete, making them more affordable.

Q5: What’s the cheapest height for a retaining wall?
Walls under 3 feet are cheapest since they require less material, labor, and engineering.