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AAC Hebel Fice Cubic House

Everything in Japan looks perfectly balanced and this modern prefab home is no exception. The "Fine Cubic" house is the modern modular home of the future! The "Fine Cubic" house is made by Asahi Kasei in Japan. This modern modular home is made mostly with a prefabricated structure and uses our favorite AAC blocks from Hebel. This modern prefab home received the prestigious Good Design Award. These modern prefab homes are made by Hebel. Hebel prefab homes are currently only sold in Europe, Japan and Australia, not in the USA. But the good news is that the Hebel building blocks are sold through Xella in the USA so this is a good solution for people willing to build their own home with the help of an architect (Xella will be happy to assist you with a local architect & builder who have experience with this material).

Ready-to-go AAC prefab homes are not available yet in the USA however. Yes, we feel your pain! But our blog will be listing more innovative ideas for building a cost-effective modern green home of the future and we hope to inspire architects, builders and future home owners in the USA with these new trends from abroad.

Autoclaved Aerated Concrete (AAC) is a precast structural product made with all-natural raw materials. In 1914, the Swedes discovered a mixture of cement, lime, water and sand that expands by adding aluminum powder. The material was further developed to what we know today as autoclaved aerated concrete.

AAC is an economical, sustainable, solid block that provides thermal and acoustic insulation as well as fire and termite resistance. AAC is available in a variety of forms, ranging from wall and roof panels to blocks and lintels.

To manufacture AAC, Portland cement is mixed with lime, silica sand, or recycled fly ash (a byproduct from coal-burning power plants), water, and aluminum powder or paste and poured into a mold. The reaction between aluminum and concrete causes microscopic hydrogen bubbles to form, expanding the concrete to about five times its original volume. After evaporation of the hydrogen, the now highly closed-cell, aerated concrete is cut to size and formed by steam-curing in a pressurized chamber (an autoclave). The result is a non-organic, non-toxic, airtight material that can be used for wall, floor, and roof panels, blocks, and lintels which according to the manufacturers, generate no pollutants or hazardous waste during the manufacturing process

AAC units are available in numerous shapes and sizes. Panels are available in thicknesses of between 8 inches to 12 inches, 24-inches in width, and lengths up to 20 feet. Blocks come 24”, 32”, and 48” inches long, between four to 16 inches thick, and eight inches high.

AAC features include structural capacity, thermal, fire, and acoustical resistance properties. With an R-value of approximately 1.25 per inch, dependent on density, AAC significantly outperforms conventional concrete block or poured concrete. Consistency in quality and color may be difficult to obtain in AAC made with fly ash. Unfinished exterior walls should be covered with an exterior cladding or parged with mortar when exposed to physical damage, dirt, and water, because atmospheric debris can collect in the open cells. If installed in high humidity environments, interior finishes with low vapor permeability, and exterior finishes with a high permeability are recommended.

Because of the thermal mass of AAC and its ability to store and release energy over time, AAC may be beneficial in climates where outdoor temperature fluctuates over a 24-hour period from above to below the indoor temperature conditioned air set point.

Check our previous blog posts for more information on AAC.