Retaining Wall Materials for a 40' × 3' Wall

A 40-foot wall 3 ft high is 120 sq ft of face — about 180 standard 16×6" blocks plus caps and base gravel. Pick a different block size, a custom block, or poured/timber/stone above.

You'll need

180 blocks

Wall area

120 sq ft40' long × 3' high

Wall blocks

18016" long × 6" high × 10" deep

Cap blocks

30~16" units

Gravel base / backfill

2.0 tons6"-deep leveling base + drainage backfill

Block cost (est.)

$900~$5/block material

Planning estimate. Adjust allowances and sample prices for your supplier; tax, delivery, and labor are not included.

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Retaining Wall Materials for a 40' × 3' Wall

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