Property 

Units

Clay Brick

AAC Block

Size

mm

230x75x115

600x200x(75 to 230)

Tolerance

mm

5-15

1.5

Strength

N/mm 2

2.5 – 3.5

3 – 4.5 (IS 2185 part3)

Dry Density

Kg/m3

1800

550 – 650 

Sound Reduction Index

Db

50 for 230 mm Thick Wall

45 for 250 mm Thick Wall

Resistance to Fire

Hrs.

2

2 to 6 

Thermal Conductivity

W/m-k

0.81

0.16 – 0.18 

Drying Shrinkage

%

–

0.04%

Parameter

AAC Block

Clay Bricks

Cost

Saving on Steel up to 15%

Zero Saving

Cement Mortar for Plaster & Masonry

Need less due to less number of joints, flat and even surfaces 

Need more because of uneven surface and excess number of joints.

Breakage

5% and less

On an average of 10 – 12 %

Construction speed

Speedy construction due to its big size, lightweight & ease to cut in any size or shape

Comparatively slow

Quality

Uniform & Consistent

Normally varies

Fitting & Chasing

A wide variety of fitting and chasing are possible

A wide variety of fitting and chasing are possible

Carpet Area

Required more as the thickness of walling material is less

Very low when compared to AAC

Availability

Anytime

Shortage in monsoon

Energy Saving

Approx. 30% reduction in air-conditioned load

No such saving

Chemical Composition

Sand or Fly-ash will be used around 60 – 70 % which reacts with Lime & Cement to form AAC

Soil is used which contains many inorganic impurities like sulphates etc. resulting in efflorescence