Mortar is a mixture of cement (or lime), sand and water used to bond bricks together or to plaster surfaces. After curing, mortar forms a strong, durable bond. In Dutch, ‘specie’ refers to the wet mix, while ‘mortel’ technically refers to the cured form — in English, both are simply called mortar.
Types of mortar
| Type | Composition | Use |
|---|---|---|
| Bricklaying mortar | Cement + sand + water | Laying bricks and blocks |
| Pointing mortar | Finer sand + cement + water | Finishing joints |
| Render/plaster | Cement/lime + fine sand + water | Plastering walls |
| Thin-bed mortar | Ready-mixed thin mortar | Aerated concrete blocks, sand-lime bricks |
| Lime mortar | Lime + sand | Heritage buildings, moisture-sensitive areas |
Mortar mixing ratios
| Application | Cement | Sand | Notes |
|---|---|---|---|
| Bricklaying | 1 part | 3-4 parts | Standard mortar |
| Pointing | 1 part | 3 parts | Finer sand (0-2 mm) |
| Rendering | 1 part | 4-5 parts | Add lime for workability |
| Foundation | 1 part | 3 parts | Stiff mix, less water |
Mixing tips
- Dry mix first — Mix cement and sand dry, then add water
- Add water gradually — Too much water makes the mortar weak and runny
- Consistency — Good when mortar stays on the trowel without sliding off
- Working time — Use within 1-2 hours, after that the mortar starts setting
Ready-mixed mortar
For DIYers, ready-mixed dry mortar (25 kg bags) is easiest: just add water. More expensive per kilo than mixing yourself, but more convenient for small jobs.
Common mistakes
- Too much water — Mortar becomes too thin, shrinks during curing, poor adhesion
- Wrong type of sand — Use sharp sand for bricklaying, not building sand (rounded grains)
- Working too late — After 2 hours, mortar is no longer usable
- Not wetting the bricks — Dry bricks absorb the water from the mortar
Related terms
- Bricklaying
- Bond pattern
- Mortar joints
- Cement
- Foundation