All You Need to Know About AAC Blocks: Types, Advantages, and Uses

Walk onto almost any construction site today, and you will spot them stacked next to the cement bags and steel bundles, pale grey blocks that look almost too light to be structural. These are AAC (Autoclaved Aerated Concrete) Blocks, and in recent years, they have rapidly emerged as the first choice among Indian Builders. The rapid adoption rate is due in part to several reasons. Below is a straightforward overview of what these Blocks are, why they have become such a popular alternative among Builders, and where they can be most effectively employed.

What Are AAC Blocks?

In essence, an AAC block is a precast, low-mass block created by mixing together fly ash, cement, lime, gypsum, water, and an expansive agent (usually aluminium powder). The expansive agent does the bulk of the work here. The mixture reacts to produce millions of small air bubbles that create the unique pore structure of the block. The Blocks are then placed in an autoclave and cured under steam and high pressure. This curing process fixes the strength of the Blocks and creates stability within the Blocks so they may be used structurally.

Types of AAC Blocks

Not all AAC blocks are made for the same job. Depending on density and where they will be used, you will typically come across three broad kinds:

• Standard AAC Blocks are primarily used for regular walling in residential and commercial structures.
• High-density AAC Blocks are heavier versions of the standard AAC block. High-density AAC Blocks provide a higher degree of load bearing capacity than standard AAC Blocks.
• AAC panels and lintels are pre-fabricated structural components for floor/roof applications, door/window lintel applications, etc., thereby reducing considerable formwork required on-site.

Reasons Builders use AAC

AAC offers several true and practical benefits that explain its increasing popularity among Builders.

• AAC Blocks weigh substantially less than traditional clay brick. Reduced weight on the structure results in reduced requirements for foundations and steel for structural support. Ultimately, this equates to significant savings for the builder.
• AAC provides superior insulation. Those very same air voids that create low density in the block allow it to hold heat, thus maintaining interior temperatures cooler in the summer and warmer in the winter. Over time, this will equate to a significantly lower utility bill for the owner/user.
• AAC Blocks do not ignite/burn, and termites do not consume them; therefore, AAC is a viable option for long-term investment in construction.
• Constructing with AAC is much faster. Larger sizes of AAC compared to standard bricks result in a lesser number of joints/mortar per square meter. With less labor and material required to complete a similar amount of work, AAC saves Builders time and money on every project.
• Since AAC possesses greater porosity than other materials, it acts as a barrier to sound waves, resulting in less noise transmission between rooms and floors.
• Utilizing AAC reduces the carbon footprint associated with a project. As fly ash represents approximately 70% to 80% of the total mix utilized to manufacture AAC, using AAC equates to placing waste generated from thermal power plant operations back into service while reducing greenhouse gas emissions associated with a given project.

Where You Will Find Them

You’ll find AAC Blocks in load-bearing/non-load bearing walls, partition walls, and increasingly in multi-story construction projects where actual reduction in structural weight is critical. You’ll find AAC Blocks equally often in residential construction as in commercial complexes, warehouses, schools, hospitals, etc. Wherever Builders require a quicker to install/build material that weighs less on the environment.

Where Shree TMT Fits In

While AAC provides the ability to construct lighter/wider walls that reduce structural dead loads, it is pointless unless what runs through those walls (the structural steel) can carry those loads. That’s where our Fe 550 D TMT bars come into play. Manufactured to conform with both IS 1786 and BIS standards, our TMT bars possess sufficient ductility and seismic performance capabilities to accommodate various forms of structural loading regardless of how those walls are constructed. Whether you’re building quickly/lightly with AAC or simply want assurance that what exists beneath the walls can withstand whatever forces may occur against them, Shree TMT bars are the steel upon which you can build.