AAC (Autoclaved Aerated Concrete) – Training Manual Key Points

A comprehensive set of 50 question-and-answer flashcards summarizing fundamental concepts, benefits, properties, applications, and technical data on Autoclaved Aerated Concrete (AAC) drawn from the MHE Training Manual.

What does AAC stand for in construction materials?

Autoclaved Aerated Concrete.

Which three main performance areas give AAC its competitive edge?

Fire resistance, thermal efficiency, and lightweight strength.

Name two fast-food chains whose buildings were shown using AAC wall or roof panels in the manual.

Burger King and KFC.

What is the standard UL fire-resistance rating often achieved by AAC blocks and wall panels?

4-hour fire rating.

Why can AAC panels float on water?

Because of their extremely low density and highly porous structure.

List any four typical applications of AAC mentioned in the manual.

Public facilities, commercial/industrial buildings, residential/multifamily, and schools (plus firewalls/shaft walls).

In terms of thermal performance, what construction element does AAC often eliminate the need for?

Separate cavity insulation or furring strips.

How many cubic meters per year can the state-of-the-art AAC plant referenced produce?

400,000 cbm per year.

Which organization’s designs (e.g., U920, K909) certify AAC fire assemblies?

UL (Underwriters Laboratories).

What size installation crew is cited as being able to set AAC panels in 4–6 minutes each?

An experienced four-man team plus one crane operator.

Name three common products in the AAC product line besides blocks.

Lintels, horizontal/vertical wall panels, and floor or roof panels.

What thickness of AAC block is the minimum for load-bearing 4-hour fire walls?

6 inches (150 mm).

Which AAC block feature makes it easy to lift units 8 inches thick or greater?

Integral handholds.

Give two economic advantages of building with AAC.

Lower life-cycle energy costs and reduced finish-material expenses.

Which benefit of AAC helps prevent termite or insect damage?

It is pest resistant (contains no organic food source).

How does AAC contribute to a safer fire environment besides endurance time?

It is non-combustible and emits no toxic gases when exposed to fire.

What typical STC value is listed for an 8-inch AAC block wall with stucco on one side?

STC ≈ 44.

Define the construction term “U-value.”

The amount of heat (BTU/h·ft²·°F) transmitted through a building element per one-degree temperature difference.

What is the approximate weight of an AAC panel relative to standard cast-in-place concrete?

About 25 % of the weight.

What two surface-treatment categories are covered for AAC walls?

Exterior surface treatments and interior surface treatments.

Which chart in the manual compares annual energy savings for AAC walls versus framing in Chicago and Phoenix?

Charts 1 and 2 on energy savings (residential and commercial).

Name one interior finish that bonds well directly to AAC without furring.

Gypsum plaster, light-weight stucco, paint, wallpaper, or ceramic tile (any one).

What is ‘thermal mass benefit’ in AAC walls?

The ability of AAC’s heat capacity to dampen and delay temperature swings, reducing HVAC loads.

Which AAC building system is specifically designed for non-load-bearing curtain walls?

AAC curtain walls or AAC infill block systems.

What standard test method is cited for AAC interior wall partitions’ 3-hour rating?

ASTM E 119.

State two ecological advantages of AAC production.

Uses natural raw materials (sand, lime, cement) and generates minimal manufacturing waste.

How does AAC affect HVAC equipment sizing according to Chart 2.0?

Allows smaller-capacity AC units compared with conventional wall systems.

What are the nominal dimensions of a standard AAC block listed in the manual?

24 inches long by 8 inches high, thickness 4 – 12 inches.

Which AAC strength classes are noted?

AC2, AC4, and AC6.

Give one reason AAC is considered environmentally friendly besides energy savings.

It contains no toxic substances and is fully recyclable/crushable for fill.

What type of joint mortar is recommended for AAC block and panels?

ANSI A118.4 latex/Portland cement thin-bed mortar.

Which AAC panel thicknesses are available for roofs and floors up to 20 ft long?

8, 10, or 12 inches thick.

What is the R-value listed for an 8-inch AC2 AAC wall (Table 1)?

R-11.5.

What is the equivalent temperature-difference (ETD) concept used for?

Comparing dynamic thermal performance of AAC to conventional walls.

Moisture graphs in the manual illustrate two properties—name them.

Water penetration depth and absorbed water versus time.

Which UL design number covers 2 inch AAC wall panels in a stud system rated 2–4 hours?

UL Design U205, U207, U208, or U358 (any one depending on layers).

What life-cycle cost category does AAC reduce through ‘fast-track construction’?

Capital (construction) costs and overall project schedule.

What does STC stand for in acoustics?

Sound Transmission Class.

Why is AAC compatible with ceramic tile installations?

Its dimensional stability and suction allow cementitious tile mortars to bond effectively.

Name two joint-firestop conditions detailed for AAC in the manual.

Floor-to-wall and head-of-wall (plus wall-to-wall or floor-to-floor).

What panel joint detail increases structural integrity in AAC roofs/floors?

Grouted key joints with reinforcing bars and perimeter ring beams.

Which institution created the house energy model comparing AAC to CMU and wood frame?

Oak Ridge National Laboratory (ORNL).

How many minutes of panel-setting time are typical per AAC panel with a crane?

Roughly 4 to 6 minutes.

Which property of AAC makes it suitable for telecom equipment buildings needing constant temperatures?

Superior thermal insulation (reduces HVAC energy demand).

What is the primary binder in AAC’s chemical composition that creates its cellular structure?

Portland cement reacted with aluminum powder to form hydrogen bubbles (autoclaving).

According to Tables 6–9, what is AAC’s specific heat used in calculations?

Approximately 0.25 BTU/lb·°F.

What construction system uses AAC ‘ValuBlock’?

Economy block walls with flat faces or tongue-and-groove ends for faster stacking.

Give one reason AAC requires fewer structural inspections on fire-rated shaft walls.

Because the panel system provides inherent fire rating without multiple layers of drywall or framing inspections.

What is the key environmental label attribute of AAC regarding combustion toxins?

No toxic smoke generation during fire.

How does AAC’s weight compare with regular concrete masonry units (CMU)?

Roughly one-half to one-third the density of standard CMU.

Which two building-code performance metrics are most improved by using AAC partitions in dormitories?

Fire safety (4-hour rating) and acoustical privacy.