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🧱 Retaining Wall Calculator

Calculate blocks, base material, and drainage for segmental retaining walls.

Enter Wall Dimensions

Total horizontal length of the wall
Maximum exposed height at tallest point
Face height of individual blocks (check your specific product)

Wall Building Guide

📏 Block Coverage Guide

Block Height Face Dimensions Coverage
Small (4") 4" × 8" or 4" × 12" 3 blocks per sq ft
Medium (6") 6" × 12" or 6" × 16" 2 blocks per sq ft
Large (8") 8" × 12" or 8" × 18" 1.5 blocks per sq ft

⚠️ Height Guidelines

  • Under 2 ft: No permit usually needed
  • 2-4 ft: May need permit
  • Over 4 ft: Check local bylaws - engineering may be required
  • Terraced walls: Set back 2× height

✅ Construction Steps

  1. Call for utility locate
  2. Excavate trench (12" deep, 24" wide)
  3. Install geotextile fabric
  4. Add and compact base gravel
  5. Lay first course (bury completely)
  6. Install drain pipe behind wall
  7. Build wall, backfilling and compacting
  8. Add cap blocks with adhesive

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