Michigan Residential Builders License Practice Test

Which type of mortar is characterized by high compression strength and is suitable for severe conditions?

1. Type N

2. Type S

3. Type M

4. Type O

The correct answer is: Type M

The type of mortar characterized by high compression strength and suitability for severe conditions is Type M mortar. This mortar is specifically designed for structural applications and can support heavy loads. It has a high compressive strength of at least 2,500 psi, making it ideal for use in foundations, brick walls, or masonry work that faces challenging environmental conditions such as high wind or seismic activity. Type M mortar is often used in applications requiring greater strength and durability; therefore, it is recommended for use below grade level or in load-bearing walls. Its formulation, which includes a higher proportion of Portland cement, allows it to withstand various stresses and harsh conditions better than lower-grade mortars. Type N, with moderate compressive strength, is better suited for above-ground applications where flexibility is more critical than strength. Type S has a higher tensile strength than Type N but is typically not as strong as Type M, making it less applicable in the most challenging scenarios. Type O, with the lowest compressive strength, is intended for non-load-bearing applications and is inappropriate for severe conditions because of its limited structural capacity.