How to Select the Right Mortar for Your Project

Guide to Choosing the Right Mortar for your Masonry Project

When completing a masonry project or repair, it’s vital to choose the appropriate type of mortar. The right mortar will ensure your masonry project endures into the future, preventing cracks and loose filling. At Houck, we always choose the type of mortar that’s best adapted to the materials, nature and environment of the project.

We’ve compiled this guide to help you choose correct mortar for all of your masonry repointing or tuck pointing projects.

Four Types of Mortar to Choose From

There are four major classes of mortar to choose from: N, S, M, and O. Each type of mortar provides unique properties and is suitable for a variety of applications. Here are descriptions of each:

• Type N: Type N is a general-purpose mortar used for interior or exterior walls that are above-grade and under normal load conditions. Type N mortar provides a good combination of workability and durability and can be chosen for most general mortar jobs.
• Type S: For increased load-bearing applications and below-grade exterior walls, Type S is recommended. It provides resistance in harsh exterior climates and is especially suitable for environments with cold winters, as it withstands deterioration from freezing and thawing.
• Type M: For ultimate load-bearing strength and resistance to the elements, Type O mortar is the suitable choice. It is less workable than other mortars, so it should only be used if you require the additional properties under load and in extremely cold conditions.
• Type O: This fourth type of mortar is relatively low-strength compared to the others. It is commonly used for repointing and aesthetic finishing, and can also be chosen for interior projects that aren’t part of a load-bearing structure.

Knowing the different types of mortar allows you to choose the appropriate product for the wall, support or feature you’re constructing or repairing. In all cases, it’s critical to follow the instructions supplied with the mortar. Be sure to maintain the correct ratio of mortar, water, and sand so your mortar is consistent, workable and safe.

Contact Houck for More Information

We invite you to contact our team here at Houck for more information. We have many years of experience in commercial and industrial building restoration and preservation and can help you choose the right type of mortar for your facility. Selecting the appropriate masonry product and application ensures your brick, stone or cinder block construction will last for years. Tell us about your project today, and we’ll be happy to offer comprehensive consultation.