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ABOUT AAC
AND ITS USE
(AUTOCLAVED
AERATED CONCRETE)
• AAC is one of the major achievements
of the 20th century in the field of wall construction.
It is a revolutionary material offering
an unique combination of high durability
and strength, low weight, unprecedented
buildability and superior ecological green
features.
• AAC is a high-quality, load-bearing and
extremely well insulating building material
produced as standard or mega blocks or
panels.
• AAC is a long proven material. It has successfully
been used in Europe since early
last century and is now among the mostly
used wall building materials in Europe with
rapidly growing market shares in Asia, the
Middle East and recently America.
• AAC is the material of choice for all
building applications, including homes,
multi-family, seniors housing, hotels, commercials,
schools, hospitals, sports halls,
etc. – an excellent building material for all
climatic conditions. It is used for all walls,
external or internal, loadbearing or nonloadbearing
walls, basement walls, infill
walls to framed structures, party walls, fire
break walls, etc.
• AAC is a steam-cured mix of sand or pulverized
fuel ash (PFA), cement, lime, anhydrite
(gypsum) and an aeration agent. The
high-pressure steam-curing in autoclaves
achieves a physically and chemically stable
product with an average density being
approx. one fifth of normal concrete. AAC
comprises myriads of tiny non-connecting
air bubbles which give AAC its diverse
qualities and make it such an excellent
insulating material.
A | AAC Blocks and Panels
Excellent heat insulation
6 times superior to clay bricks.
Fire resistant
more than 4 hours in 9 cm thickness.
Noise absorption
is superior than traditional clay bricks.
Easy workability
and 3 times faster than traditional masonry.
7

8
A | AAC Blocks and Panels
QUALITIES OF AAC
BLOCKS AND PANELS
Compare always cost and features of a
ready-installed wall of AAC with a wood
stick wall or a wall of bricks or concrete
blocks. The finished AAC wall features all
benefits, such as:
Ecological green building
Qualities:
• energy efficient
• best thermal insulation, 6 to 10 times
better than regular concrete = heat and
aircon saver
• environmentally friendly, non-toxic
• unsurpassed fire-resistance =
– life saver
– property saver
– insurance cost saver
• excellent sound absorption, ideal for the
hotel industry
• production process develops non-toxic
gases
• no waste of raw materials (water, fresh
cut-offs, etc. are all fully recycled into
production)
• industrial byproducts like PFA (pulverized
fuel ash = fly ash) of coal fired
Unsurpassed Fire-rating (average)*:
Block thickness, (mm)
minimum (inch)
Fire-rating (hours)
Non-load bearing wall DIN*
ASTM**
50
(2)
75
(3)
power plants can be used and are turned
into useful building materials
• recycling of breakage, rejects, etc.
• lowest energy consumption per cbm
(cft) during production in comparison to
other wall building materials
• saves resources: 1 m 3 (1 cft) of AAC
requires 0,2 – 0,25 m 3 of raw materials
only (0,2 – 0,25 cft)
Economic Qualities:
• competitive price = high economy
• high durability = long life, impervious to
rot or pest
• hurricane and earthquake resistant
• increased comfort and functionality of
the building
Physical Qualities:
• good workability, better than wood (can
be sawn, drilled, nailed, milled on site)
• large in size, however light weight =
considerable savings of structural costs
(loadbearing walls, foundation, piling
etc.)
• low weight results in easy handling and
rapid laying by the mason
• high load-bearing strength
• dimensional accuracy
115
(4 1 /2)
150
(6)
0,5 1 – 1,5 2 3
4
4 4 4
Load bearing wall DIN* 0,5 – 2 1 – 3 1,5 – 2 2 – 3 3
175
(7)
200
(8)
240
(10)

… MORE ABOUT AAC?
ENERGY EFFICIENCY
Great Energy Efficiency
High energy efficiency is one of the determining
characteristics of autoclaved aerated
concrete. AAC‘s cellular structure gives
it a thermal efficiency 10 times higher than
that of aggregate concrete and six times
better than clay brick. Consequently, buildings
made of AAC are warm in winter and
cool in summer.
With buildings consuming 40% of global
energy, greater use of AAC, both in construction
and renovation, offers an immediate
solution to cutting the energy consumption
of residential and non-residential
buildings across the globe.
AAC‘s excellent inherent thermal insulation
properties not only reduce the need
for heating and cooling, thereby cutting
carbon dioxide emissions and combating
climate change, but also make the use of
additional insulation materials unnecessary.
EU insulation requirements can be
met by using AAC alone. By contrast, aggregate
concrete, clay brick and calcium
silicate masonry units need to be used
in combination with insulation products,
thereby adding to their cost and environmental
impact.
AAC is energy-efficient over its whole life
cycle. Its production requires less energy
than other construction materials and its
light weight saves energy in transportation.
Because of the considerable thermal mass
AAC has the ability to store and release
energy over time. An increased comfort in
climates where outdoor temperatures fluctuate
strongly over a 24 h period.
FIRE RESISTANCE
Excellent Fire resistance
Autoclaved aerated concrete provides the
highest security against fire and meets the
most stringent fire safety requirements.
Due to its purely mineral composition, AAC
is classified as a non-combustible building
material. It is both resistant to fire up to 1200° C
and, unlike other construction materials,
heat-resistant.
Therefore AAC can be used as a fire wall
to prevent fire from spreading, thereby
protecting lives and economic assets. In
principle a fire wall should last up to four
hours, but tests have shown that an 150
mm thick AAC fire wall can resist at least
for six hours. In a real blaze, an AAC fire
wall even survived intact for 120 hours.
Some insurance companies offer reductions
in fire premiums for buildings
equipped with AAC fire walls.
In addition to internal fire walls, constructing
outer walls of AAC contributes significantly
to fire safety as most blazes start
outside buildings.
Besides being fire- and heat-resistant, AAC
does not give off any smoke or toxic gases,
which can endanger human life more than
fire itself.
STRUCTURAL
PERFORMANCE
Outstanding structural
Performance
Autoclaved aerated concrete is extremely
strong and durable despite its light weight.
AAC‘s solidity comes from the calcium silicate
that encloses its millions of air pores
and from the curing process in a pressurised
steam chamber (autoclave). Its excellent
mechanical properties make it the
construction material of choice for earthquake
zones.
AAC‘s light weight ensures that the foundations
of a building are lightly loaded, yet
it is strong enough to bear several floors.
It retains its properties for the entire life
of a building. AAC resists wind, rain and
storm and does not decay or rot. In general,
changing outside temperatures cannot
damage AAC.
A | AAC Blocks and Panels
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10 A | AAC Blocks and Panels
RESOURCES
Autoclaved Aerated Concrete (AAC) is an
environmentally responsible building material
that conserves material and energy
usage in manufacture as well as energy efficiency
of the building.
High resource Efficiency, low
environmental Impact
Autoclaved aerated concrete‘s high resource
efficiency gives a low environmental
impact in all phases of its life cycle, from
processing of raw materials to the disposal
of AAC waste.
Raw Materials
AAC is made from naturally existing materials
that are found everywhere
– lime, fine sand, other siliceous materials,
water and a small amount of aluminium
powder (manufactured from
a by-product of aluminium) – plus
cement.
Production
Thanks to continuous efficiency improvements,
production of AAC demands relatively
small amounts of raw materials per
m 3 of AAC (1 m³ of raw materials results in
Consumption of raw materials and energy needed for production of
building materials *
1600
1400
1200
1000
800
600
400
200
0
Clay bricks
p = 1,2 kg/m 3
Consumption of raw materials in kg/m 3
Consumption of energy in kWh/m 3
5 m 3 of finished AAC), 5 times more than
any other construction products. No raw
materials are wasted in the production
process and all production offcuts are fed
back into the production circuit.
The manufacture of AAC requires less energy
than for all other masonry products,
thereby reducing use of fossil fuels and associated
emissions of carbon dioxide (CO 2 ).
Energy is also saved in the curing process
since AAC is steam cured at relatively low
temperatures and the hot steam generated
in the autoclaves is reused for subsequent
batches. Industrial-quality water is used
and neither water nor steam are released
into the environment. Non-toxic gases are
created in the production process.
Transportation
AAC‘s light weight also saves energy in
transportation. As AAC is up to five times
lighter than concrete and two to three times
lighter than clay brick CO 2 emissions are
significantly reduced during transport.
Reuse, Recovery and
Disposal
Throughout the life cycle of AAC, potential
waste is reused or recycled wherever possible
to minimise final disposal in landfill.
Porous clay
masonry units
p = 0,8 kg/m 3
Calcium silicate
masonry units
p = 1,4 kg/m 3
AAC
masonry units
p = 0,4 kg/m 3
*Source: FeBeCel handbook 2000: Le Béton Cellulaire – Matériau d’ Avenir, p. 32

Blocks
• length up to 625 mm (2 ft)
• height 200 – 400 mm (8‘‘ to 16‘‘)
• thickness 50 – 400 mm (2‘‘ to 16‘‘)
Megablocks
• length 625 to 1250 mm (2 ft to 4 ft)
• height 625 mm (2 ft)
• thickness 100 – 400 mm (4‘‘ to 16‘‘)
Panels
• length
– floor high 2.50 – 4.30 m (8 ft to 14 ft)
as vertical wall panels
– long up to 6.00 m (20 ft)
as horizontal or vertical wall and roof/floor panels
• width 625 mm (2 ft)
• thickness 75 – 300 mm (3“ to 12“)
Strength class
according
to DIN
*Density *Average Compressive
Strength
Thermal
Conductivity
t/m³ lb/cft N/mm² psi W/mk (BTU·in/ft²h°F)
PP2-035 0.35 22 2.5 350 < 0.11 < 0.76
PP2-040 0.40 25 2.5 350 0.11 0.76
PP2-050 0.50 30 2.5 350 0.14 0.97
PP4-055 0.55 33 5.0 700 0.14 0.97
PP4-060 0.60 35 5.0 700 0.16 1.11
PP6-070 0.70 40 7.5 1000 0.18 1.24
*Ref. DIN 4165
Note: The compressive strength and density to be achieved depend on the raw material quality and on the mix
formula.
Strength
Class
Nominal Dry
Bulk Density
Density
Limits
Compr.
Strength
psi (MPa)
Average
Drying
Shrinkage
Thermal
Resistance
(8 in. wall
thickness)**
R-value
lb/ ft³/ kg/ m³ lb/ ft³/ kg/ m³ min (%) (hft² °F/BTU)
AAC-2 25 (400) 22–28 (350)–(450) 290 (2.0)
31 (500) 28–34 (450)–(550) 11.5 – 9.2
AAC-4 31 (500) 28–34 (450)–(550) 580 (4.0) ≤ 0.02
37 (600) 34–41 (550)–(650) 9.2 – 7.4
44 (700) 41–47 (650)–(750)
50 (800) 47–53 (750)–(850)
AAC-6 37 (800) 35–41 (550)–(850) 870 (6.0)
44 (700) 41–47 (650)–(750) < 7.4
50 (800) 47–53 (750)–(850)
Ref. ASTM: C1386-07
**including air film coefficients
A | AAC Blocks and Panels
TYPICAL
SIZES
(other sizes
possible)
EUROPE
11
Physical
Characteristics
(DIN EN)
USA
Physical
Characteristics
(ASTM:
C1386 - 07)