When you are laying brick and block you have to have the right type of mortar mix. Generally there are two types, Type N and Type S. Which one you use will depend on what you are doing.

Type N is a general purpose mortar that is used for above grade exterior walls and interior load bearing walls. It has a medium compressive strength of 750 psi.

Type S is a premium quality mortar mix that has the highest amount of Portland cement and sand it can hold without shrinking during the curing process. It is used for below grade applications such as foundations, retaining walls, swimming pools, etc.. This type has a high compressive strength of 1,800 psi.

When it comes to mixing your own mortar there are a couple common questions that people ask. For example, how much mortar mix do I need to apply to a brick wall? How much water should I add? How long can the mix be kept before using? Let’s take a look at each question in more detail.

Have you ever wondered why there are so many different mortar mixes? And which mix you should use in your construction project? We often get asked questions like, how much mortar mix do I need to apply to a brick wall?

To answer all these questions, we have put together everything you need to know about mortor mixes.

Mortar Mixes

What is Mortar?

Mortar is a mixture of sand and cement which allows the bricks or blocks to be bonded together. Once applied, the mortar has to set and cure (much like concrete) and when it does, the wall will become rigid.

It’s important that you choose the right mortar mix for your project as different types of mortar mixes have different uses. If you fail to do so, your project could fail.

Northeastern Masonry and Restoration is a full service masonry contractor specializing in the restoration and preservation of historic buildings throughout New England. Our company employs only skilled, experienced artisans who use traditional and modern techniques to perform the highest quality work.

We are proud of our work, and we depend on our reputation to attract new customers. We therefore take great care to ensure that every project we undertake is completed with the utmost attention to detail, craftsmanship and integrity.

Mortar Mixes

There are many types of mortar mixes, each designed for a specific purpose or application. Selecting the correct mortar mix for your project requires a basic understanding of the different mortar mixes available in the market. The following paragraphs explain some of the most common mortar mixes available today:

Mortar Mix Types (N) – This type of mortor is normally used for interior construction where there is little exposure to water or temperature extremes. Mortar Mix Type N can be used for exterior construction when mixed with a water repellent additive.

The amount of mortar you will need to lay bricks depends on the size of the bricks and the style of bond you are using. As a general rule for a standard running bond, a 25kg bag of mortar will lay approximately 500 bricks or 7 square metres.

To make one cubic metre of mortar you will need approximately 13 bags. Bricks come in different sizes and so do mortar joints. Therefore to work out how much mortar you require to build a wall, you first need to decide if your walls are going to be built in stretcher or header bond.

Stretcher Bond: The bed joint is laid with the long side (head) of the brick exposed and the side joints are made with half bricks, known as stretchers. With this method all bricks run lengthways.

Header Bond: In this bond each alternate course is laid as headers with the remainder built as stretchers.

When calculating your requirements, use this guide:

A single wall 10m long 1m high in stretcher bond requires approximately 60 bags of mortar mix, or

A single wall 10m long 1m high in header bond requires approximately 70 bags of mortar mix.

1. What is the difference between mortar, concrete, and cement?

Mortar is a mixture of sand, cement and water that sets hard when dry. It is used to bond bricks or blocks together, fill and seal gaps and help hold retaining walls in place.

Concrete is a mixture of sand, gravel and cement that forms a strong building material used for floors, walls and columns. Concrete can also be used for paving driveways, sidewalks and patios.

Cement is a fine powder made from limestone and other minerals that sets hard when mixed with water. Cement is not the same thing as concrete (it’s one ingredient in concrete).

2. What kind of mortar mix should I use for a stone wall?

Stone walls are often built using lime mortar mixes rather than cement-based mixes because lime mortar helps the wall breathe, which prevents moisture from building up inside the wall causing eventual damage to the wall’s structure. Lime mortar mixes are slower-setting than cement based mixes, so they require more skill to apply; but they have less shrinkage which makes them less likely to crack over time.

The best known of these is the lime mortar mix, which is suitable for use in buildings up to the early twentieth century. This is a traditional lime sand mortar mix which has been used in construction for thousands of years. It is still widely used today, especially in conservation and restoration work.

The main advantages of this type of mortar are that it has good bonding qualities, low shrinkage and excellent breathability. The main disadvantage is that it takes time to mature and will not harden fully for at least a year after being laid. This means that a lime mortar mix will not be suitable for areas where a lot of movement is expected.

Partly due to its long maturation time and partly due to the fact that it is difficult to produce accurately in large quantities, this type of mortar tends to be mixed on site by experienced craftsmen rather than bought as a pre-mixed bag from a manufacturer. However, some building materials merchants do sell pre-mixed bags of lime sand mortar mix for those who don’t want to make their own or who are working on smaller projects.

At least from a technical perspective, you can’t go wrong with a 1:3 mix in terms of strength. Regardless of what your application is, this will cover you for any sort of masonry construction up to 2 stories.

A 1:3 ratio by volume mix would be 1 part cement powder and 3 parts sand (1/4 x 3 = 3/4, so there are 3 parts sand for every 1 part cement).

This right here is the most common mortar mix that you’ll use for just about any type of masonry work. This proportion will provide a medium strength mortar with a medium to fast set time that’s also fairly workable.