Cost Benifits of Lightweight Aerated Autoclaved Concrete (AAC) Block

WHY AAC BLOCKS ARE COST SAVING PRODUCT ?

Saving in Cost of Structure

• AAC blocks are one third lighter than conventional clay bricks, thereby reducing the dead weight of the structure drastically.
• Light weight structure decreases construction cost due to reducing steel, Cement and Excavation.
• Case Study Shows almost reduction in steel = 15 % reduction in cement =10%.
• Due to reduction in dead weight, Reduction in consumption of steel and cement and lesser.
• Excavation for foundations, construction time is reduced which in turn results in savings in labor cost and overheads..

Savings in Mortar

• AAC blocks are 7 times bigger than the size of the conventional bricks. Bigger size means less number of joints.
• Less joints results in lesser quantity of mortar for building. There is overall 60% reduction in use of Mortar.
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  BRIXOLite High Strength Lightweight

Savings in Plaster

• AAC blocks have uniform shape and texture, which gives even surface to the walls.
• There is overall around 35% reduction in the cost of plastering.

Reduction in Wastage Due to less breakages

• Unlike conventional clay bricks which are prone to breakages, AAC blocks have almost nil breakages.
• There is over all 65% reduction in cost due to practically no wastage the input cost.

Reduction in HVAC Load

• AAC blocks are resistant to thermal variations. It reduces total load of refrigeration and air conditioning.
• Though initial installation cost may remain same but AAC blocks reduces operation and maintenance cost drastically.
• There is over all 25% saving in operation cost.

Savings in Power Infrastructure

• Due to lesser HVAC load, cost of power infrastructure i.e. is lesser capacity of transformer, DG set, and Cable etc also reduces considerably which in form results in savings in electricity charges.

Manufacturing and Advantages of AAC Blocks

It is produced from 5 natural materials: Fly ash, lime, cement, gypsum and water, combined with aluminum powder. The production process consists of the following steps.

·         Dosing and mixing of fly ash with lime, Ordinary Portland Cement (OPC), gypsum, lime and stabilizers a high dosing speed at very high accuracy.

·         Casting and rising/pre curing of the mixture to enable the fresh mix to rise and harden to a firm green cake with the volume of the mould.

·         Tilting mould cakes with the tilt manipulator on to a cutter machine and oiling to prevent the sticking of the green cakes for reuse.

·         Horizontal and cross cutting the cakes by cutter which are equipped with broken-wire-detection system.

·         Curing with a steam at pressure in autoclave system for 12 hrs period.

·         A post autoclaving, after buffering and de-stacking of hardened cakes from the cooking frames to the packaging line for final packaging.

The special combination of these substances yields a material with excellent construction properties such as structural strength, lightness, thermal insulation and fire resistance.Much of the material used in the manufacturing process is recaptured from non-toxic mine tailings, dramatically reducing the amount of raw materials required for production.  Additionally, waste generated during production is recycled back into the manufacturing process.  AAC Block is compatible with sustainable building practices since it requires fewer raw materials to produce and is completely non-toxic.  Production of AAC Block is designed to minimize waste and maximize recycling of materials. 

Lightweight 

Weighing approximately 1/5th as much as concrete.  This attribute makes the design and construction of AAC buildings easier and less strenuous. The lighter weight doesn't compromise strength as AAC has a compressive strength more than 30 Kg/cm2.

Energy Efficient  

The closed air cell construction of AAC provides superior insulation equivalent to R-values between 20-24 depending on the thickness of blocks.  It is possible to save up to 40% on energy costs. The breathable qualities of AAC allow energy to move through the blocks very slowly, thus ensuring that the interior temperature remains consistent.

Fire Resistant  

AAC is non-combustible and transfers heat slowly.  As per general laboratory testing AAC has a fire rating of 4 hours for a 4" non-load bearing wall.  AAC built structures provide homeowners with added piece of mind in fire prone landscapes.

Versatile  

It is available in different thickness as per requirement. Because it can be shaped by ordinary power tools with ease, AAC Block lends itself to aesthetically pleasing designs like curves, arches and domes.

Easy to Install  

AAC Block can be drilled, cut, cored, shased and shaped on-site.  Plumbing and Electrical lines can be routered directly into the block.

Sound Absorbing  

 In addition to providing thermal insulation, dead air cells within the block reduce the passage of sound this makes AAC Block ideal for projects next to airports, highways, apartments, resorts or high-density neighborhoods.

Cost Advantages  

The installed cost of AAC Block is competitive with other building materials.  Faster construction time, saving in plaster and mortar because of even and smooth surface also reduced cement and sand requirement by up to 35% to 40%, almost zero long-term maintenance.

Five Green Building Blocks - The Hindu

FEATURES » HABITAT

June 14, 2013

Updated: June 17, 2013 17:07 IST  

"How sustainable your home is depends on how green the construction material is", says Nirthya Rajan

Using green building material while constructing your home is the easiest way to make it sustainable. Here's a list of five products made of components that are renewable and environmentally responsible.

Fly ash bricks

Fly ash bricks or FAB converts the industrial waste of fly ash into an effective building material. The manufacturing process uses less energy and the bricks come in uniform shapes and various sizes. As a building material it has gained importance in the construction sector in the recent past as it is light-weight, has higher strength (less breakage during transportation), offers high resistance to sound, has low water absorption and is a good thermal insulator. It also makes the job easier for electricians and plumbers as chiseling can be done with ease. FAB is used for load bearing walls and can result in making finer finishes with even surfaces. FABs are costlier than normal bricks by around 18 -25 per cent. However, on a larger scale, the cost of the project can be reduced as the dead load over the columns and beams are lesser, wastages minimal and they require less labour time.

Autoclaved aerated concrete

Autoclaved aerated concrete (AAC) is a derivative of fly ash that is combined with cement, lime and water and an aerating agent. AAC is produced as blocks and panels. It is an approved eco-friendly building material that comes from industrial waste and is made from non-toxic ingredients. With AAC, your construction process can be about 20 per cent faster.

It weighs only about 50 per cent of a standard concrete block and possesses high thermal insulation and is acoustics-friendly. It also has better fire resistance than fly ash and is non-combustible. It’s non-allergic and hence maintains the quality of air within a building without changing its properties over time.

Using AAC can reduce construction cost by about 2.5 per cent for buildings such as schools and hospitals and reduce the running costs of hotel and office buildings by to 30 to 40 per cent over time.

Compressed earth blocks

Compressed earth blocks (CEB) have been in use for a long time and are made from clay, sand and cement. They are biodegradable and can be made locally from any soil with a proper mix of ingredients like sand and cement. It offers fire resistance and is sound proof. Building cost can go down by 15 per cent or more. CEBs are, however, not suitable for smaller homes and buildings.

Insulite

Insulate is a green roofing material with a base from silica obtained from industrial waste and developed using a unique formula containing fibourous polymer liquid.

This permanent roof insulation material is cost effective, light weight and has wide area of applications. The thermal conductivity is 10 to 12 times lesser compared to normal brick bat reducing the heat transmission by 20 to 40 per cent. Insulite is termite and rodent proof and has high durability. It is also easy to apply and takes close to four times lesser time than brick bats to be completed.

Particle boards

Particle boards commonly used as a material for flooring, roofing and furniture, have in the past few years come to replace solid wood as building material. Innovations such as the use of plantation timber, which form rapidly renewable resources instead of hard wood for their manufacturing, have made this material further sustainable. More economical than solid wood, these ‘green’ particle boards can help bring down building costs to a great extent. They are available in the thickness range of 2mm to 6mm. Particle boards have low moisture absorption, high internal bonding and dimensional stability.

How green is my home?

Use energy efficient lighting systems and maximise daylight

Indian Green Building Council’s green checklist:

- Reuse salvaged material wherever possible

- Use material with recycled content

- Use local material as far as possible

- Use green-certified or salvaged wood

- Use low VOC material, paints and adhesives

http://www.thehindu.com/features/homes-and-gardens/5-green-building-blocks/article4813910.ece

Autoclaved Aerated Concrete (AAC) Blocks

BRIXOLite I  HIGH STRENGTH LIGHTWEIGHT  I  AAC BLOCKS 

It is a lightweight masonry made of fly ash, lime, gypsum and cement, and autoclaved at high pressure. During the chemical process millions of tiny bubbles are formed causing the mixture to rise in a manner similar to bread rising. After the casting is set, it is cut into the panel or block dimensions by pulling it through wires strung on a loom. The casting is then fully cured in a large steam chamber called an autoclave.

Application

Ideal for Masonry work for High Rise , Commercial and Industrial Buildings.

Special Features

• BRIXOLlite is green building product manufactured using 70 % of recycled material.
• BRIXOLlite is 65 % less in weight than conventional clay bricks. It saves approximately 15 % to 20% of the steel requirement in reinforcement. It’s excellent size/weight ratio allows faster construction work.
• It’s uniform and bigger size of blocks enable speedy construction.
• High compressive strength makes BRIXOLlite solid, therefore recommended for load bearing wall also having minimum breakage .
• Dimensional accuracy result, BRIXOLlite an extremely easy to install, save mortar and plaster consumption.
• It can be available in different sizes according to project’s requirement.
• The porous structure of BRIXOLlite provides a high acoustic insulation.
• BRIXOLlite blocks are having very low thermal conductivity and therefore a high thermal energy efficiency is achieved. It reduce the inside temperature which results in cost savings for heating and cooling.
• One of the important property of extremely higher fire resistance gives product rating at least 4 hours and more.