YOU CAN BUILD WITH SOIL-CEMENT BLOCKS

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Removing the fresh blocks from the Ram calls for a delicate touch, as the bricks are plastic and fragile when newly formed. The Ram's instruction booklet suggests that "you place hands flat at the ends of the block, being careful not to damage the corners or edges, and then gently lift the block from the mold box". We had more success pressing our palms flat against the long, narrow sides of the bricks instead (as shown in one of the accompanying photographs).

THE CURING PERIOD

Place the bricks as soon as possible on a flat, non-absorbent surface (a board or slab of cement covered with sheets of plastic is ideal) in a shady environment to cure. Be sure to set each block on edge and to space the bricks far enough apart so that they don't touch. And please note that bare ground—which will draw water from the blocks so rapidly that they'll be weakened and may even crack?is NOT an acceptable surface upon which to age your bricks.

If possible, the curing site should be located directly adjacent to the Ram since you'll find it difficult to carry the freshly molded bricks very far. Ken Kern?in The Owner-Built Home's chapter on pressed block construction?suggests that you erect your building's roof first, so that you can then use the protected area underneath as a curing "yard".

The slower the soil-cement blocks dry, the stronger they'll be. Which means that?during the first four days of their cure?you should keep your bricks covered with plastic. Also, beginning 24 hours after they leave the Ram, the soil?cement blocks must be thoroughly sprinkled three times a day with the fine spray from a garden hose. The bricks may be stacked on the fourth day, but the sprinkling should be continued for another eight days. Finally, three weeks after leaving the mold, the blocks can be used in construction.

PUTTIN' BLOCKS TO USE

The same building techniques used with concrete blocks can be employed with your bricks of pressed earth. Before laying soil-cement blocks, though, it's a good idea to dip them in water to prevent them from absorbing moisture from the mortar (thereby weakening it) used to hold them together.

As usual, courses of the bricks should be laid in such a way that the vertical seams in one row coincide with the center-points of the blocks in the course above. Also, the mortar in all joints should be no more than one centimeter (four-tenths of an inch) thick.

Because our winters are so cold and wet here in eastern Washington, we felt it prudent to seal our blocks (and thus waterproof them for good). To do this, we applied a clear acrylic masonry sealer to the finished soil-cement walls. Numerous other paint and plaster finishes, of course, would have done the job just as well.

It's sad, but there aren't really many books around on the subject of building with pressed-earth blocks. One fact-packed text I can recommend to anyone interested in this kind of construction is the Handbook for Building Homes of Earth, by L. Wolf skill, W. Dunlop, and B. Callaway  Also, of course, Ken Kern devotes a chapter to the topic in The Owner-Built Home.

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