What Is Mortar And What Types Of Mortar Are Available?
Mortar is necessary. You may have asked what is mortar and what types of mortar are available?
But have you thought about mortar and its uses?
What Is Mortar?
Mortar is a mixture of cement, water, and other materials. Builders use it to lay bricks, stone, and seal gaps. It is also for making patterns on stone, brick, and wood structures.
History Of Mortar
Mortar has been around for thousands of years. Limestone and other materials were once popular. The material was mixed with clay and water, which formed a binder.
The material became less popular. But in the 60s, mortar became popular in the US.
Difference Between Mortar, Concrete, And Cement
You need cement to make concrete. Concrete is a mixture of cement, water, and gravel.
With mortar, it’s different. It’s like concrete but has less or no gravel. It is a binder used for bricklaying while concrete is a solid material meant for other things.
Mortar and concrete contain cement. Structures require concrete while mortar binds structures.
Types Of Mortar
Each type contains different materials. Each type is labeled with a letter on the mix bag.
There are five types available to the public.
N-Type Mix
Withstood PSI – 750
Recommended On – exterior, above-grade, interior, load-bearing, and soft stone
For exteriors, above-grade, interior, load-bearing, and soft stone
Type N is for exteriors. Sometimes you’ll see it on interiors. It works well under intense heat, cold, and storms. The formula includes 1 part Portland cement, 1 part lime, and 6 parts sand.
It’s versatile and the most common mix among homeowners and businesses. It is an all-purpose mortar mixture.
O-Type Mortar Mix
Withstood PSI – 350
For interior use and non-load bearing.
Type O mix has a lower strength. It has half the strength of an N-type mix and is used for interiors. It is ideal for repairs and small interior projects.
S-Type Mix
Withstood PSI – 2000
For below grade, masonry foundations, manholes, retaining walls, sewers, patios, pavement
Type S is strong and has a minimum withstood PSI of 1800. It works for most projects but isn’t used on interiors. It is strong enough to drive or walk on, so it is often used in paved walkways.
Type S can also be mixed with other materials for an even stronger grade and withstood PSI. Only one other grade is stronger than it, though it can withstand almost anything. So it is used more often than the other type.
Related: 8 Greener Alternatives For Concrete As A Building Material
M-Type Mortar Mix
Withstood PSI – 2500+
For heavy loads, masonry below grade, foundations, retaining walls, driveways
Type M mix has the highest amount of cement. It is the strongest type available. M-type must have 2,500 PSI compressive strength.
It isn’t suitable for interiors or visible areas. It works well with natural stone as its texture is similar after it dries.
K- Type Mortar Mix
Withstood PSI – less than 100
For restoration purposes.
Type K is uncommon. When restoring and filling cracks, this is the go-to brand. It’s thin and can fill cracks and cover surfaces as it doesn’t have a thick texture.
Working With Old Mortar
If you want to repoint mortar, it’s easy if you know how to mix it. Repointing is the act of repairing and filling cracks in brick walls.
In the past, mortar had lime in it. Today, it has Portland cement because of its strength. In older homes, lime mortar was popular, but it’s not as strong as it today.
You can make it stronger by adding a fresh layer and filling cracks. For weak spots, chisel and fill the hole with new mortar to make it stronger.
Portland cement is recommended, high-grade can hurt soft bricks and stone. Make sure to use one of the lower-grades. You can look for repointing or make it yourself.
Lime mortar is common as it doesn’t break down old structures like Portland cement.
Remove Damaged Mortar
You have two choices. You can chisel the small, weak areas or remove the structure and rebuild it.
If you rebuild, you’ll need to work. Start at the top and take the structure down one brick at a time. Remove each brick with a chisel and scrape it off.
Vacuum
If you remove the top layer and problem areas, you’ll need to vacuum the holes. This isn’t necessary if it isn’t broken, but it’s helpful.
Wet The Area
Mortar won’t stick to dry areas. Wet the area where you’re applying the new material. Spray the area and let it sit for a minute. Don’t saturate but moisten it.
Use a spray bottle to apply an even amount of water.
Fill The Cracks
Use the pointing trowel to fill the gaps. The trowel is smaller than the larger gaps so you can fill them. Pack it tight. If you fill the cracks with too much, remove the excess after it dries.
Let It Dry Halfway
After it has dried, scrape off the excess and give it a smooth surface. You can finish the facing or leave it the way it is. It will take about a month before it hardens.
How To Make Mortar
Because mortars are natural, they are easy to make. While mix is recommended, some like to start from scratch.
Here are the three ways to make it:
Portland Cement, Lime and Sand
This is the oldest method and works well. This is good to make strong Type S.
- 1 bag of Portland cement.
- ½ bag of hydrated type S lime.
- 28 shovelfuls of masonry sand.
- 7 to 8 gallons of water.
How To Mix:
Start with water. Put 2/3 to 3/4 of the water into the mixer. Then add the cement and lime. Add the sand last. Use the last of the water until you have the right texture. Mix for about five minutes.
If you want stiff, strong mortar, use less water. If you want thinner, use more water. Always opt for not adding enough water because you can add more later. You can’t remove any water.
Masonry Mortar
Masonry mortar has cement and lime and it’s easier to use. If you want Type S, do this:
- 1 bag of masonry cement.
- 18 to 20 shovel scoops of masonry sand.
- 5 gallons of water.
How To Mix:
Start with water. Pour 2/3 to 3/4 of the water in the mixer. Next, add the sand. Use the remaining water until it is the right texture. Mix for about five minutes.
Pre-mixed Mortar
This is the easiest to make. It is like masonry mix and has the sand added too. The only thing you must do is add water.
- 1 bag of mix
- 5 to 6 quarts of water.
How to Mix:
Pour 3/4 of the water into the mixer. Add the mix. Then use the remaining water as needed. Let it sit for a few minutes and then turn it off and let it fall. Then, turn it on and mix for a few more minutes.
If you don’t have a mixer, use a wheelbarrow and mixing tools. It works, but it will be harder to use.
Frequently Asked Questions (FAQ)FAQ
Is Mortar Water Resistant?
No. By itself it’s not waterproof. If you want water-resistant, you can buy it pre-mixed or add things to make it waterproof.
What Temperature Is Too Low For Mortar?
When using or curing it, outdoor temperatures should be between 70 to 80 degrees Fahrenheit. In temperatures below 40 degrees, you’ll need to heat it beforehand.
If you don’t heat it in colder climates, it will take longer to dry and won’t be as strong.
What Is The Average Lifespan Of Mortar?
When laying bricks, the material lasts between 20 and 30 years. Signs to look for that indicate it’s too old and needs fixing include cracking, blistering, warping, and disintegration.
Mortar Conclusion
Before you use mortar, learn about the types. The advantages include how it binds surfaces so they won’t slide. It offers stability as it molds itself according to the structure. When laying bricks, it can help save time.
Remember, cement mortar needs more time to harden. It also has low tensile strength and will shrink after it dries. Another thing to consider is its low resistance to chemicals.