Rammed Earth Homebuilding

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After the formwork has been filled with compacted earth, the form panels are removed and reset for another section of wall

After the formwork has been filled with compacted earth, the form panels are re moved and reset for another section of wall. Unlike concrete, the forms need not remain on while the material cures.

Water, Water...

Moisture is the lifeblood of the soil, but it can wreak havoc if the building and the site aren't prepared for a deluge. Lowlying building sites are, of course, subject to flooding. Driveways and

pathways above a house may channel water into a doorway. Wind-driven rain can beat against window frames with enough force to creep around the sash. Saturated earth walls tend to lose their thermal efficiency and may become subject to accelerated surface weathering. Depending on the amount of annual rainfall in the region, water-related issues may play a very big part in the siteselection and design processes.

Where winter rains are extremely heavy, great care must be taken to assure rapid runoff away from the building. If positive control systems are not installed, water may back up against foundations and floor slabs, eventually migrating underneath the structure and generating unhealthy conditions in the house, or possible settling of the foundation walls.

These oversized columns support wooden trellises providing seasonal shade to a southern patio. The first and most important line of defense against groundwater damage is careful siting of the house. Study the land for signs of water flows. Avoid sites that are clearly water drainages.

Picturesque riverbeds, today a peaceful habitat for rabbits and quail, was originally gouged out of the land by water.

The water will come again. The second line of defense against water-related problems is the finish grading around the building. Ground should always slope away from the house on all sides so that water will run away quickly from the building and never toward it.

If water is allowed to back up against the walls, it will eventually work its way into the house. In some cases water can build up enough pressure to actually dislodge a building from its foundation. Drain lines can be buried at the base of the walls as additional diversionary measures, but surface drainage is always critical. Lastly, take special precautions to ensure that neither driveways nor walkways create natural watercourses leading toward the doors.

Even a little footpath can become a streambed after a downpour. The third level of protection, which like grading relates more to construction than to the selection process, is the team of roof overhangs, gutters, downspouts, and underground drain lines. In high rainfall or snowfall areas, overhangs and gutters are absolutely essential. Where the soil is heavy or drainage poor, use underground lines to carry the water from the roof away from the building.

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