How do you choose the right concrete repair mortar?

Choosing the right repair mortar depends on five factors: repair depth (thin-layer vs structural), orientation (horizontal, vertical, or overhead), load requirements (foot traffic vs forklift), exposure conditions (internal, external, chemical, freeze-thaw), and cure time needed. For shallow repairs under 30mm, a polymer-modified repair mortar like Sika MonoTop-412 N works well. For deep structural repairs over 50mm, use a flowable micro-concrete that can be poured or pumped. Overhead and vertical work requires thixotropic (non-slump) mortars that stay in place. All repair mortars should comply with BS EN 1504-3 and match the thermal expansion coefficient of the host concrete to prevent debonding.