Proportions
| Portland cement | 1 part |
|---|---|
| Hydrated lime | 0.25 parts |
| Sand | 3 parts |
| Typical strength | 2,500 psi · 17.2 MPa |
Mortar
Mortar mix ratio for a retaining wall
Retaining and below-grade walls carry high loads and ground contact, so they call for Type M — the strongest ASTM C270 mortar.
Recommended mix
1 : 0.25 : 3portland cement : hydrated lime : sand
Type M mortar — about 2,500 psi (17.2 MPa).
Planning reference. Typical proportions and strength for general work, not a structural mix design. Load-bearing and structural work must follow your local building code and a qualified engineer's specification.
Why this mix
The strongest ASTM C270 mortar (min 2,500 psi). Used where high compressive strength and ground contact matter — foundations, retaining walls and load-bearing masonry below grade. Low workability.
Once you know the mix, the volume calculators tell you how much of it to buy — cubic yards, cubic metres and the bag count in every size.
Nearby