Which type of mortar is typically recognized for its superior strength and is often used in structural applications?

Type M mortar is known for its superior strength, making it the most suitable choice for structural applications. This type of mortar has a high compressive strength of 2,500 psi or greater, which allows it to withstand significant loads and stress. Type M is often used in heavy-load-bearing walls, such as foundations, retaining walls, and where structural integrity is paramount.

The formulation of Type M mortar includes a higher proportion of cement compared to other types, which contributes to its robust nature. Its durability under harsh weather conditions and resistance to both moisture and pressure further enhance its utility in construction.

In contrast, Types O, S, and N are generally formulated for less demanding applications; Type O has lower strength and is primarily used for non-load-bearing walls, Type S has moderate strength suitable for above-grade walls, and Type N is suitable for general masonry work in above-grade applications but is less robust compared to Type M. This distinction makes Type M the ideal selection when high strength is a requirement in masonry construction.