Aerated blocks are a type of innovative concrete blocks that contain more than 80 percent air. They are also called autoclaved aerated concrete (AAC). Aerated concrete is a group of materials you would describe as lightweight concrete. Previously, lightweight concrete is an arbitrary term; however, aerated concrete blocks have numerous advantages, such as light, better insulation (sound and light), and stronger than conventional blocks
Key Takeaways
- Aerated blocks (AAC) are lightweight concrete blocks with over 80% air, offering better insulation and strength than conventional blocks.
- AAC blocks are made by introducing air into the concrete mix through various methods, creating a uniform cellular structure.
- The cost of AAC blocks depends on logistics, shipping, and proximity to manufacturing facilities, with closer proximity reducing costs.
- Aerated blocks have low density (25-50 lb/ft³), with heavier blocks offering higher strength but lower insulation, and a lower modulus of elasticity than conventional concrete.
- AAC blocks speed up construction, are durable and mould-resistant, provide excellent fire resistance, are cost-effective, and enhance energy efficiency.
Manufacturing of AAC Blocks
To make an aerated block, air is introduced into its composition; furthermore, there are three ways to bring the air into its composition.
- By using a porous aggregate, which retains air within the aggregate itself
- Through a single-size aggregate, thereby leaving interstitial air voids
- By directly introducing air or other gas into cement slurry in a manner that whenever the cement sets, it forms a uniform cellular concrete.
Famously, AAC is described as a cement paste that has gas bubbles introduced inside them. However, aerated concrete contains a substantial amount of siliceous materials in the form of silica flour, ground burnt shale, and pulverised fuel ash.
AAC Block Price
Cost is a significant factor when considering aerated blocks. Often, people evaluate numerous aspects beyond just the price of AAC blocks. They take into account logistics, shipping expenses, and convenient transportation methods. However, if your construction site is near a manufacturing facility, you can benefit from reduced costs.
Properties of Aerated Concrete Blocks
Density
Aerated blocks have a low density, ranging between 25-50lb. The lighter aerated concrete blocks are used for insulation but have indifferent strength. Nevertheless, the heavier grade of AAC blocks has higher straight with low insulation value. The density range for the heavier grade ranges from 40 to 50 lb. per cubic foot.
Compressive Strength
The assessment of declared strength values from several sources is considered difficult due to different testing methods, shapes, and samples. The size and shape are significant because they can affect the outcome of the block by 30 percent.
Modulus of Elasticity
Aerated blocks have a low modulus of elasticity compared to conventional concrete.
Environmental Considerations
AAC blocks are produced with a focus on sustainability, requiring less raw material and energy compared to other building materials. This makes them an environmentally friendly choice.
Aerated Blocks Usage
- Building Components: AAC blocks are commonly used for constructing walls, floors, and roofs because they are lightweight and easy to work with.
- Fire Safety: AAC blocks provide exceptional fire resistance, taking anywhere from two to six hours to burn through based on their size.
- Sound Insulation: Due to their effective soundproofing properties, AAC blocks are suitable for use in noisy environments such as hotels and movie theatres.
Benefits of Using Aerated Blocks
AAC blocks are important building tools that have been in existence since 1920. They are beneficial for many reasons:
- Aerated blocks (AAC) are lightweight concrete blocks with over 80% air, offering better insulation and strength than conventional blocks.
- AAC blocks are made by introducing air into the concrete mix through various methods, creating a uniform cellular structure.
- The cost of AAC blocks depends on logistics, shipping, and proximity to manufacturing facilities, with closer proximity reducing costs.
- Aerated blocks have low density (25-50 lb/ft³), with heavier blocks offering higher strength but lower insulation, and a lower modulus of elasticity than conventional concrete.
- AAC blocks speed up construction, are durable and mould-resistant, provide excellent fire resistance, are cost-effective, and enhance energy efficiency.
- AAC bricks are made with fewer raw materials and less energy, making them a more sustainable building option.
Potential Risks of Using RAAC & Innovative Building Materials
RAAC in recent times has unfortunately made the news for troubling reasons. In September 2023, Schools Minister Nick Gibb announced that schools needed to close due to “safety risks” after facing several incidents over the summer where RAAC failed without warning—both in schools and other buildings.
While RAAC has its benefits, this situation serves as a cautionary tale that new building technologies need to be carefully tested for long-term durability to avoid unexpected and potentially dangerous issues. It highlights the need to balance innovation with proven reliability in construction. Despite the concerns, RAAC is still seen as an important material for the future, with new low-carbon concrete similar to AAC blocks continually being tested.
Conclusion
Thinking of using aerated blocks for your next building project? MGN Builders Merchants has a wide range of aerated blocks at the most competitive prices. These blocks are used in many building constructions, including residential, commercial, industrial, hotels, and hospitals. AAC blocks’ lightweight material provides the best thermal and sound insulation you need for your home today.
Frequently Asked Questions
How do AAC blocks compare to regular concrete blocks in terms of thermal conductivity?
AAC blocks have low thermal conductivity, providing excellent thermal insulation. They help maintain stable indoor temperatures efficiently. This leads to energy savings and a more comfortable environment. Regular concrete blocks have higher thermal conductivity and are less effective at insulating. This can result in higher energy usage for climate control in buildings.
Can AAC blocks be used in high-rise buildings or are there limitations?
AAC blocks provide many advantages especially for high-rise buildings. They offer strong structural support, excellent fire safety, and good energy efficiency. However, it’s important to address issues like permeability, load-bearing limits, and handling needs. Proper design and construction methods can make AAC blocks a key part of sustainable high-rise projects.
Are there any specific tools or equipment required to work with AAC blocks during installation?
Working with AAC blocks requires specific tools for proper installation and handling. Essential equipment includes pallet forks, masonry trowels, rubber mallets, notched trowels, builder’s levels, carbide-tipped hand saws, safety glasses, and dust masks. Additional tools like power drills and electrical routers are needed for tasks such as drilling holes and creating chases for conduits.
What is the typical lifespan of AAC blocks and how does it compare to other building materials?
AAC blocks last much longer than many traditional building materials. They resist moisture, fire, and pests while offering superior thermal insulation and structural stability. This durability, combined with cost-effectiveness and environmental benefits, makes AAC blocks a top choice for construction projects.
