Retaining Wall Calculator
Calculate blocks, backfill gravel, and total cost for retaining wall construction
Calculate Retaining Wall Materials
Wall Configuration
Cap row is a decorative top row that extends above the wall height
Wall Dimensions
Block Dimensions
Backfill Configuration
Minimum 30cm (12") recommended for proper drainage
Material Pricing
Retaining Wall Materials & Cost
Calculations used:
- • Rows = ceil(0.00m ÷ 0.000m) = 0 rows
- • Columns = ceil(0.00m ÷ 0.000m) = 0 columns
- • Wall blocks = 0 × 0 = 0 blocks
- • Backfill volume = 0.30m × 0.00m × 0.00m = 0.00 m³
- • Gravel weight = 0.00 m³ × 1346 kg/m³ = 0 kg
Analysis & Recommendations
Example Calculation
Garden Retaining Wall Example
Wall dimensions: 30 feet long × 10 feet high
Block size: 10 inches × 15 inches concrete blocks
Configuration: No cap row
Backfill: 12 inches thick gravel backfill
Block price: $5.00 per block
Gravel price: $2.00 per pound
Calculation Results
Rows = ceil(10 ft ÷ 10 in) = ceil(120 ÷ 10) = 12 rows
Columns = ceil(30 ft ÷ 15 in) = ceil(360 ÷ 15) = 24 columns
Wall blocks = 24 × 12 = 288 blocks
Block cost = 288 × $5.00 = $1,440.00
Backfill volume = 1 ft × 30 ft × 10 ft = 300 ft³
Gravel weight = 300 ft³ × 84.03 lb/ft³ = 25,209 lbs
Gravel cost = 25,209 lbs × $2.00/lb = $50,418.00
Total cost = $1,440.00 + $50,418.00 = $51,858.00
Common Block Sizes
Construction Tips
Minimum 30cm backfill thickness for drainage
Level foundation prevents wall failure
Use geotextile fabric behind blocks
Install drainage pipe at base level
Check local building codes for permits
Buy 10-15% extra materials for waste
Understanding Retaining Wall Construction
What is a Retaining Wall?
A retaining wall is a structure designed to hold back soil and prevent erosion on sloped terrain. They're essential for creating level areas in landscaping, preventing soil movement, and managing water drainage around properties.
Why Backfill Matters
- •Provides proper drainage behind the wall
- •Prevents water buildup and pressure
- •Reduces freeze-thaw damage
- •Extends wall lifespan significantly
Calculation Formulas
Rows = ceil(Wall Height ÷ Block Height)
Columns = ceil(Wall Length ÷ Block Length)
Wall Blocks = Columns × (Rows - Cap Row)
Backfill Volume = Thickness × Length × Height
Gravel Weight = Volume × 1346 kg/m³
Safety Considerations
- Height limits: Walls >1.2m may need permits
- Foundation: Proper base preparation crucial
- Drainage: Minimum 30cm gravel backfill
- Engineering: Consult professionals for tall walls