Type S Mortar Mix Ratio Calculator
Calculate the exact amounts of Portland cement, hydrated lime, and sand needed for your mortar mix. Perfect for retaining walls, below-grade foundations, and structural masonry.
Mortar Volume & Recipe
Enter your sand volume and mortar type to calculate the exact ingredients required
How much sand do you have or need to use?
Select the unit of measurement for your sand.
Choose the ASTM standard mortar type for your project.
Choose how you want the ingredient amounts displayed.
Mortar Mix Calculation
Exact ingredients required for your masonry project
Enter your sand volume and mortar type above, then click Calculate Mix to see the exact ingredients required.
Standard Mortar Types
Different masonry projects require different mortar strengths. Always check your local building codes, but here are the standard ASTM C270 proportions by volume.
| Mortar Type | Mix Ratio (Cement:Lime:Sand) | Compressive Strength | Common Uses |
|---|---|---|---|
| Type M | 1 : 0.5 : 4.5 | 2,500 psi | Below-grade, high strength foundations |
| Type S | 2 : 1 : 9 | 1,800 psi | Below-grade, retaining walls, patios |
| Type N | 1 : 1 : 6 | 750 psi | General purpose, above-grade walls |
| Type O | 1 : 2 : 9 | 350 psi | Interior, non-load bearing repointing |
Mortar Mix FAQ
Everything you need to know about mixing mortar, choosing the right type for your project, and ensuring a strong, durable masonry build.
The standard Type S mortar mix ratio is 2 parts Portland cement, 1 part hydrated lime, and 9 parts sand by volume. This provides a high compressive strength (minimum 1,800 psi) and excellent below-grade performance.
Type S mortar is commonly used for below-grade applications, such as foundations, retaining walls, manholes, and patios. It is also used for structural load-bearing walls above grade where high strength and lateral movement resistance are required.
While Type S mortar is very strong, it is generally too rigid for standard above-grade bricklaying. Its high strength and low flexibility can cause it to crack or damage softer bricks during temperature changes. Type N mortar (1:1:6) is usually recommended for general above-grade brickwork.
Type S mortar typically reaches its initial set within 24 to 48 hours. However, it takes a full 28 days to achieve its maximum compressive strength and fully cure. It should be kept damp and protected from freezing during the curing process.
The main difference is their compressive strength and flexibility. Type S mortar (2:1:9) has a much higher compressive strength (1,800 psi) but is less flexible. Type N mortar (1:1:6) has a medium compressive strength (750 psi) but is more flexible, making it better for general above-grade applications and softer masonry units.