Innovation is an important part of construction – making improvements to the quality, sustainability, and efficiency of materials. An example of an evolutionary improvement in construction materials is Autoclaved Aerated Concrete (AAC) blocks.
Due to their lightweight, durability, and environmentally friendly features are also increasing in popularity. In this blog we will look at the types of AAC blocks, advantages for use, and AAC block hardeners to increase their strength and performance.
Table of Contents
What Are AAC Blocks?
Autoclaved Aerated Concrete (AAC) blocks are precast building materials that are lightweight, strong, and very versatile. They are made from a mixture of lime, sand, cement, water, and an aerating agent, which is then cured under high pressure and temperature inside an autoclave. The end product is a lightweight yet robust block type that results in many benefits to residential and commercial buildings.
Types of AAC Blocks
There are various categories of AAC blocks, and each category serves specific functions. There are three major classes:
1. Solid AAC Blocks
Solid AAC blocks are the most recognizable type of AAC block. Solid AAC blocks have a solid, dense composition and a uniform structure that provides structural integrity.
Solid AAC blocks furnish strength and stability while contributing to a lower overall weight to the structural system. Because of their strong composition, solid AAC blocks can have I-shaped block systems which allows for very effective reinforcement against loads in a horizontal direction.
When solid AAC blocks are combined with wide flange beam reinforcement, they provide structural integrity in load-bearing walls, columns, and groundwork. Solid AAC blocks are appropriate for residential and commercial construction.
- Applications: Solid AAC blocks are appropriate for use in walls, columns, and ground work in appropriate load bearing systems.
- Size: Generally, solid AAC blocks are available in sizes ranging from 600mm to 625mm in lengths, 200mm in height, and thicknesses varying from 100mm to 400mm.
2. Hollow AAC Blocks
Hollow AAC blocks have empty cavities, or voids, formed in the center of the block which allows for a significant reduction in weight between solid and hollow AAC blocks.
Their hollow cavity design contributes to lightweight construction along with thermal insulation and sound vapor-proof construction properties. Hollow AAC blocks are designed to carry lower load and are preferred for non-load-bearing applications, partition walls, and interior merchandise.
- Applications: Hollow AAC blocks are advisable to use for partition walls, internal walls, and non-load bearing applications.
Size: Typically, they come in sizes of 600mm to 625mm long, 200mm high, and can vary in thickness from 100mm to 300mm thick.
3. AAC Block Panels
AAC block panels are large, precast concrete panels made from AAC blocks that are used for walls and various structural components. They are practical in making partition walls, external walls, and floors.
Due to the large size of the panel, construction time becomes much quicker and the overall method becomes more efficient. AAC block panels are very energy efficient because of the insulation properties.
- Applications: They are especially ideal for external walls, partition walls, and floors.
- Size: The panel size can vary, but are typically available in dimensions of 2400mm x 600mm, 2400mm x 1200mm, or custom panel sizes as per project site requirements.
4. AAC Blocks for Cladding
AAC blocks for cladding are very thin block dimensions that are used as a lightweight block for a decorative layer. These types of blocks have great thermal insulation and are typically used for modern construction providing aesthetically pleasing façades.
AAC blocks also provides durability and helps protect against weathering while also reducing overall energy consumption of a building.
- Applications: Applicable for external cladding, façades, and other building facings.
- Size: AAC blocks are usually thinner than regular AAC blocks, generally between 75mm-100mm thick.
Benefits of AAC Blocks
The increased applications of AAC blocks in the construction industry stem from the considerable benefits they provide over normal construction materials. The main benefits of AAC blocks:
1. Lightweight
AAC blocks are very lightweight compared to standard clay or concrete blocks, which allows them to be easily transported, handled, and installed; providing reduced labor costs and a faster-priced schedule. Being lightweight also reduces the weight of the building on the foundation.
2. Thermal Insulation
One of the major features of AAC blocks is the thermal insulation that they provide. The porous structure of these blocks work to keep the building cooler in the summer and warmer in the winter, providing a lesser reliance on air conditioning and heat and reducing the overall energy consumption of the building.
3. Fire Resistance
AAC blocks are exceptionally fire-resistant. They will not melt, even in high-temperature inclement weather, so they are a good choice for buildings that require fire safety. AAC blocks also do not emit toxic gas or smoke in a fire, which increases the building’s occupant’s safety and the safety of the structure itself.
4. Acoustic Insulation
The porous nature of AAC blocks gives them good soundproofing capability. The insulated block construction reduces noise travel making AAC blocks good for buildings in urban living or areas with high noise levels or places where privacy is essential for residential home construction.
5. Durability
AAC blocks are durable and long-lasting. They are resistant to cracking and other types of construction damage, assuring the integrity of the structure for years to come. This durability results in a lower overall maintenance cost, therefore making AAC blocks more economical building materials in the long run.
6. Eco-Friendly
AAC blocks are composed of natural and sustainable materials and are 100% recyclable. They are manufactured with relatively lower CO2 emissions compared to conventional concrete and materials and are green construction materials. The insulating properties of AAC blocks also provide energy-efficient buildings which benefits the environment.
7. Easy to Install
Because of the lightweight and manageable nature of AAC blocks, they are easy to install. AAC blocks are also easy to cut and shape which cuts installation time. The reduced need for mortar and cement in the joints also helps with ease of installation as well.
8. Pest Resistant
AAC blocks are resistant to termites, fungi, and other forms of pest infestations. This makes them a better building material option for buildings that are located in a humid environment, or where pest infestations are either periodically, or regularly a concern.
Role of AAC Block Hardener
AAC block hardeners are often added to AAC blocks to enhance their strength and longevity. AAC block hardeners are additives that are mixed into AAC blocks during their manufacturing process to enable the blocks to perform at their best. Hardener’s improve the blocks water resistance, compressive strength and help reduce the risk of cracking.
Utilizing an AAC block hardener will help ensure that the structure retains its durability over time. The added durability and strength will allow the blocks to hold consistently under the various weight and weather conditions they may be subjected to.
It is especially important to use an AAC block hardener in instances of extreme weather, and/or in areas where there are large moisture content levels in the surrounding environment.
Conclusion
The construction industry has been revolutionized by AAC blocks in that they comply with building durability and structural performance while being a lightweight and energy-efficient option.
With the range of AAC block types available, including solid, hollow, panel, and cladding blocks, a broad spectrum of construction types and buildings can be addressed.
The associated benefits of AAC blocks, including, but not limited to, thermal insulation, fire resistance, and soundproofing properties make them a preferred building option in residential and commercial spaces alike.
