Retaining Wall Materials for a 40' × 3' Wall
A 40-foot wall 3 ft high is 120 sq ft of face — about 180 standard blocks plus caps and base gravel. Switch the material above for poured concrete, timber, or natural stone.
You'll need
180 blocks
Wall face area
120 sq ft40' long × 3' high
Wall blocks
180Concrete block — standard (≈16×6" face)
Cap blocks
40~12" cap units
Gravel base / backfill
2.0 tons6"-deep leveling base + drainage backfill
Block cost (est.)
$900~$5/block material
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