What is "mortar"? Differences from concrete and points to ...

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1. What is mortar?

Mortar is a building material consisting of cement + sand (fine aggregate) + water. Sand (fine aggregate) here refers to small aggregates with a diameter of 5 mm or less. The base cement, in powder form, becomes a paste when mixed with water and hardens over time. When cement hardens, it becomes hot, and this heat can cause the surface to dry out and crack easily. However, by mixing sand, the amount of cement can be minimized and the heat generated can be reduced. Furthermore, replacing some of the cement with sand has the added benefit of reducing costs.

1-1. Mortar applications

• Finishing material Mortar is a soft, fine-textured material used mainly as a "finishing material" for walls and floors. Mortar can be finished in various patterns, such as by stretching it with a trowel or by daring to express unevenness in the application. It is also used for furniture tops and fixtures.
• Jointing material Because of its high adhesive strength, it is also used as a "jointing material" when tiling or piling bricks.
• Base material Because it can create a smooth surface, it is sometimes used as a base material before painting or applying cloth.

1-2. Mortar types

There are several types of mortar. Here we will discuss some of the most common ones.

• Cement mortar The least expensive, most commonly used, and most common mortar.
• Non-shrinking mortar (repairing material) Mortar that does not shrink when it sets and does not crack. It is less viscous and drier than cement mortar, and is used to fill gaps in concrete walls and to repair cracks that have occurred. Because of its high cost, it is rarely used extensively.
• Polymer cement mortar (base material) A cement mortar to which a polymer is added. It is often used as a base material because of its higher impact resistance and adhesiveness compared to cement mortar.
• Resin mortar (finishing and repairing material) Mortar using resin instead of cement. Because it is elastic, crack-resistant, and waterproof feature, it is often used in kitchen, vanity tops, and other water-using areas. Since its high performance comes at a high cost, it is recommended to incorporate it at key points in accordance with the intended use.
• Instant mortar Type of mortar which is a mixture of cement and sand that can be used simply by mixing with water. It is often used in DIY projects because it is easy to handle.
• Color mortar Mortar that is colored by mixing pigments with white cement is called colored mortar. Ordinary cement is gray because it contains iron. However, when pigments are added to gray cement, the coloring is not good, so white cement with minimal iron content has been introduced. Japanese-style buildings, for example, sometimes use "sumi mortar," which is a general gray mortar mixed with sumi(charcoal) ink to make it blackish.

1-3. Difference from concrete

The main difference between mortar and concrete is material and usage. The difference is whether or not sand (fine aggregate) is included. Concrete is made of cement + sand (fine aggregate) + gravel (coarse aggregate) + water. In other words, concrete is mortal + gravel (coarse aggregate). Gravel here refers to large pieces of gravel with a diameter of 5 mm or more. The gravel in concrete is combined with cement, making it more resistant to cracking than mortar. When reinforcing steel bars are added, the result is "reinforced concrete," which is used for building columns, beams, walls, and other structure. When gravel is added, the texture is rougher and more rugged than that of mortar.

Advantages of mortar finish

The following are some of the advantages of mortar finish. Broadly speaking, those are design, fire resistance, and low cost.

2-1. High design quality

Above all, its high design quality is the secret of its popularity. It is a versatile material that blends easily into any space and can be finished in a stylish manner. One way of finishing can completely change the impression, from a modern look to a gentle atmosphere. In particular, "hand-rubbed" plastering, which is done by hand using a trowel, requires a high level of skill, and it is said that it takes a long time for a plasterer to become a full-fledged plasterer. The wide variety of finishing patterns makes it a very deep industry.

2-2. Fire-resistant

Mortar is made of cement and sand, which makes it fire-resistant. For this reason, it is also recognized as a "fire-resistant" or "fireproof" structure, which is required for exterior walls in urban areas.

2-3. Relatively inexpensive construction

Another advantage is that it is cost-effective. Because of the low cost of materials, mortar can be installed at a lower cost than tiling or flooring the floor. However, the cost can be higher if you are particular about the paint pattern or use high-performance mortars such as no-shrink mortar or resin mortar.

3. Disadvantages of mortar finish

3-1. Prone to cracking

Although mortar replaces some of the cement with sand, the risk of cracking is inevitable. Cracks on the surface are not that much of a problem, but if there is a large crack on the exterior walls, rainwater can penetrate into the walls, causing deterioration and leaks. The skill of the installer will affect not only the finish but also the durability, so be careful when selecting a contractor.

3-2. Requires regular maintenance

Regular maintenance is necessary to prevent deterioration due to cracks, stains, and mold; we recommend that you have the builder inspect the site once every 10 years or so to repair or repaint. However, when there are large cracks of about 1 mm in width, there is a risk of leaks, so it is safer to repair them as soon as possible.

Is mortal available for DIY?

Depending on the location and scale of the construction, DIY is not recommended. In fact, cement and instant mortar are easily available at hardware store and online, and are also used in DIY projects. However, there are some precautions to be taken when handling mortar, such as amount of water, how it is mixed, and how the trowel is used. If you are looking for a beautiful finish, it is definitely better to leave it to the professionals.

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Below is a summary of what is and is not suitable for DIY.

4-1. What is suitable for DIY?

• Repairing cracks (other than exterior walls) Minor cracks can be repaired by ourselves. We recommend using a product in a tube called "repair material." However, cracks on the exterior walls should be looked at by the builder, as there is a risk of leaks.
• Block piling Piling blocks to create flowerbeds and other exterior structures is one of the easiest DIY projects. However, when stacking blocks high, there is a risk of them falling over, so it is best to ask a professional to do the job.
• Part of an interior wall Mortar begins to harden at the water-mixing stage, so it must be worked quickly. It is not recommended to make a lot of mortar at once, so it is best to try a small area first.
• Making small objects Since you can freely create shapes, making flowerpots, objets d'art, and small objects in mortar is recommended.

4-2. What is not suitable for DIY?

• Interior walls (e.g., one large surface) If mortar is applied in several coats, the color may be uneven or the finish may vary depending on the area coated, and in some cases the finish may not be very beautiful. When applying mortar to a large area, it is recommended to have a professional do the work, as speedy and clean application is required.
• Exterior Walls The exterior walls are an important part of a house's performance. Since many processes and advanced techniques are required to protect the house from the wind and rain, leave it to a professional installer.
• Floors The floor finish is particularly prone to cracking. To prevent cracks as much as possible, we recommend laying mortar with a thickness of 2~3 cm and placing reinforcing wire mesh inside. A considerable amount of mortar is required, so leave this to the installer as well.

6. Summary

We have introduced the characteristics of mortar and examples of its construction. It is very important to choose the right material for your home, not only for its good design, but also for its characteristics and advantages and disadvantages. The architect will explain the characteristics, functions, and maintenance of each material, and then propose a design that is perfect for you. If you are interested in examples above or want to build a house that you can live in for a long time with peace of mind, please use japanese-architects.com's architect referral service. japanesse-architects.com's architectural advisors will introduce you to the perfect architect based on your wishes and imagination.

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Cement is often confused with concrete or mortar. However, it's important to recognise that cement is a powdery substance composed of limestone, clay and other minerals. When combined with water, cement forms a paste that hardens and binds other materials together. The most common type of cement used in construction is Portland cement (CEM I), which is a versatile and reliable binder.

If you&#;re seeking clarity on cement versus concrete , or have questions about mortar versus concrete, this article will provide the information you need. We&#;ll explore the key differences between these construction components, their unique characteristics and their specific applications.

Concrete: a robust building material

Concrete is a composite material made from a mixture of cement, water and aggregates such as sand, gravel or crushed stone. The cement and water combine to create a paste that coats the aggregates, which then harden as the mixture cures. The resulting material is strong and durable construction material. This makes concrete an excellent choice for a wide range of structural applications, for instance:

Basements: basecrete is an economical and durable option, ideal for direct floor finishes like shed bases.

Driveways: drivecrete is a high-quality concrete designed for domestic driveways and pavements.

Foundations: foundationcrete is a durable concrete designed for single-storey building foundations without steel reinforcement. And others.

Each of these concrete types is formulated to provide specific properties and performance characteristics, catering to the diverse needs of construction projects. Whether for a simple garden path or a complex foundation, we at Concrete2You provide a concrete mix tailored to meet every requirement.

Comparing cement and concrete

When talking about the difference between cement and concrete, it's important to note that cement is an ingredient used in the creation of concrete. Cement acts as a binder that holds the other components of concrete together, while the strength and durability of the final product come from the combination of cement, water and aggregates. Concrete is a versatile and robust material used in a wide variety of construction projects, whereas cement is primarily utilised as a binding agent. For more detailed information, you can read our article &#;Difference between Cement vs. Concrete&#;.

Mortar: the binding agent for masonry

Mortar is a mixture of cement, sand and water. Its primary purpose is to act as a binding agent, joining bricks, stones or other masonry units together in construction projects. Mortar creates a strong bond between the individual masonry units and helps to distribute the weight and pressure evenly. It's also essential for sealing gaps between bricks or stones, preventing moisture penetration and providing a finished appearance to masonry work.

Understanding mortar versus concrete

While both mortar and concrete share cement as a key ingredient, they serve distinctly different purposes in construction. Mortar is used to bind masonry units together, while concrete is a structural material used for building foundations, walls and other load-bearing elements. The main difference between the two lies in their composition: mortar has a higher proportion of sand, making it more pliable and easier to work with, whereas concrete includes aggregates for added strength and durability.

Cement, concrete and mortar in construction

Understanding the differences between cement, concrete and mortar is essential for selecting the appropriate materials for your construction projects. Cement is the binding ingredient that, when combined with water and other materials, forms either concrete or mortar. Concrete is a strong, durable material used for structural purposes, while mortar is a more pliable material used to join masonry units together. With this knowledge, you can make informed decisions about the materials you use in your home building and improvement endeavours.

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