1. Compatibility with refractory bricks:  Mortars must be compatible with the composition of refractory bricks with which they are to be used. This also depends on the temperature under operating condition which the Refractories will be placed.

2. Heavy load / moving condition: In the applications which mortars are required to withstand heavy load or moving condition, such as in cement kilns and kiln cars, the mortars should have high strength at room temperature

3. Temperature: If the temperature under operating condition doesn’t exceed 1,000⁰ C, the selected mortars should have high refractoriness at room temperature

4. Convenience: Wet Type Mortar is easier to use and requires less time than Dry type Mortar.

5. Chemical reaction: Mortars must be able to endure chemical reactions in kilns and furnaces.