How the Mortar Converter Works
The Mortar Converter divides mortar mass by wet mortar density. The default 2.15 kg/L fits a standard 1:4 cement-sand mortar.
Pick the mortar type
Type M, S, N and O mortars, lime mortar and thin-set differ in density.
Enter the density
Use the table value for wet mortar.
Enter the mass
Type the mortar or dry-mix bag weight in kilograms.
Read the volume
Use the liters to estimate bricks laid per batch.
Mortar Converter Formula
The mortar formula is V = m ÷ ρmortar. A 10 mm joint brick wall uses about 0.03 m³ of mortar per square meter of single-skin wall.
- ρmortar
- Wet mortar density, kg/L
Worked Examples
- 25 kg dry-mix bag: mixed with about 3.5 L water = 28.5 kg ÷ 2.15 = 13.26 L.
- Wall of 10 m² single skin: 300 L × 2.15 = 645 kg of wet mortar.
- Lime mortar: 20 kg ÷ 1.80 = 11.11 L.
Mortar Converter Conversion Table
1 liter of wet cement-sand mortar weighs about 2.15 kg (4.74 lb). The table lists 6 mortar types.
| Mortar Type | Density (kg/L) | Liters per 25 kg | lb per ft³ | kg per m³ |
|---|---|---|---|---|
| Lime mortar (NHL) | 1.800 | 13.89 | 112.4 | 1,800 |
| Type O (1:2:9) | 2.000 | 12.50 | 124.9 | 2,000 |
| Type N (1:1:6) | 2.100 | 11.90 | 131.1 | 2,100 |
| Cement-sand 1:4 | 2.150 | 11.63 | 134.2 | 2,150 |
| Type S (1:½:4½) | 2.150 | 11.63 | 134.2 | 2,150 |
| Type M (1:¼:3) | 2.200 | 11.36 | 137.3 | 2,200 |
Ratios in brackets are cement : lime : sand by volume per ASTM C270.
What is a Mortar Converter?
A Mortar Converter is a calculator that converts mortar weight into wet volume using the density of the mortar mix.
Mortar binds bricks and blocks with cement or lime, sand and water. ASTM C270 sets four cement-lime mortar types, M, S, N and O, from strongest to weakest.
Lime makes mortar lighter and more workable. Natural hydraulic lime (NHL) mortars suit older masonry that needs to breathe and flex.
What are the Uses of a Mortar Converter?
There are 4 main uses of a Mortar Converter.
Bricklaying estimates
Masons convert wall area into mortar bags.
Plastering
Plasterers convert render coats into mix volume.
Tile setting
Tilers convert thin-set bags into coverage.
Scaffold loading
Supervisors check tub weights on scaffold lifts.