Cast earth construction

Introduction

The need to be competitive in the emerging global economy is a hot topic in many countries today. Industrialization, such as the prefabrication of building components, is critical to competitiveness. Many prefabrication technologies deliver a better product because building is done in a quality controlled, sheltered environment. Just as importantly, prefabrication can dramatically improve productivity.

The productivity growth of labour intensive construction industry is declining and must be improved to survive in an internationally competitive market. Builders will have to develop new construction methods and adapt existing methods from other industries and countries.

An awareness of the current trends and latest innovations in prefabrication and industrialized construction is essential.

The destruction of urban Europe and Japan during the Second World War, combined with the post war baby boom, created a need for housing for millions of people.

The existence of a single large client (the state) and a need for rapid construction combined to provide fertile soil for a boom in the development of industrialized construction techniques. Japanese and European construction firms pioneered many new processes, and today they are still making significant progress in prefabrication and industrialized construction technology. New construction methods and materials, computers and robots are being developed to constantly improve productivity.

One Japanese firm, Sekisui, ushers home buyers into a facility where they use three dimensional computer images to "custom design" their own home. Sekisui builds over 70, 000 of these luxury houses a year using industrialized construction technology, and can deliver a finished home within three months.

Innovations in the areas of materials, computers and robotics are improving building quality. As construction evolves into an industrialized process, new construction methods and building systems are also being developed to assemble prefabricated components. World's builders can take advantage of these advances.

We’ll try to examine some alternative methods in construction through this report.

Alternative Construction Methods

Adobe construction

Adobe construction is one of the oldest forms of building technology, still being used in the United States today. This form of building has been used in the desert Southwest for nearly 1, 000 years, while its historical origins can be traced back to Rome, as early as the 1st century A. D. Adobe, an Arabic word, describes a construction method in which clay bricks are molded while still wet and cast small enough to shrink without cracking. These bricks were usually laid up with a mud mortar.

The desert Southwest played host to the largest concentration of adobe structures, for many reasons. The Spanish settlers who came to this area found the thick walls of the adobe structure were easy to build with indigenous materials, while the completed structure’s thermal mass soaked up the solar heat, therefore keeping the houses cool during the day and warm at night.

Cast earth construction

Cast Earth construction is a method of construction similar to rammed-earth. It is the work of Michael Frerking, an architect and general contractor in Prescott, Arizona. He has been working with rammed-earth technologies in Arizona for over 20 years. Cast-earth construction, unlike rammed-earth, uses a mix of gypsum plaster in place of traditional portland cement. Cast-earth is cast into forms using current poured concrete techniques and tools.

Cast-earth can be batched in a local concrete plant, delivered using regular trucks, and pumped through regular concrete pumps into regular concrete forms. It is this regular use of a new technology that makes cast-earth an economical choice to rammed-earth and many other construction techniques. In addition to lower labor and materials charge, cast-earth is considerably stronger, the set time is shorter, therefore bringing an age old construction technique into the twentieth century.

Cordwood construction

Cordwood construction in its simplest state, is simply the stacking of wood logs with mortar between and a roof overhead. This simple building technology has been around indefinitely, with no known origin. The present state of cordwood building, with Rob Roy as its chief architect and engineer, has become a valuable form of environmental building technology. A cordwood masonry home can be built with simple tools and techniques, using short pieces of wood.

Cordwood buildings use short logs, stacked widthwise with a mortar mix between. The high thermal mass and energy efficient construction, coupled with its economical building process, make this a worthwhile building technology for the present and the future.