Hollowstone LLC molds new paradigm for concrete masonry

After a four-and-half-year struggle with the U.S. Patent and Trademark Office, inventor John August received US Patent #7905070 for an “Interlocking Mortarless Structural Concrete Block Building System.” Years went by as the assigned examiner kept denying his claims; each time the inventor had to rebut the examiner’s take on the proposed patent, but finally 18/22 claims were approved.

Having a good idea is only the beginning of a struggle that can take years, and a patent’s term begins with date of application. The new block is aptly named Hollowstone. The vision for it began over 20 years ago with the concept that for the concrete industry to be more successful it needed to create “user friendly” CMUs.

This block and building system resolves the “user friendly” problem with a concept that makes building with concrete block much like toy building kits with simple CMUs, yet highly functional, strong, and versatile. As shown on the opposite page, the system has only four units, but yields curves and intersecting or “T” walls without blind spots. The blocks are wet cast for three reasons: 1) the limitations of hydraulic press; 2) creating a product with smooth surfaces; and 3) molds that can be used by anyone from do-it-yourself homeowners to developers. They can be either site- or plant-cast.

Hollowstone & The Future

A few years ago, this author obtained a building permit in Hawaii for an all-concrete home using the non-agency approved Hollowstone block system. The chief of the building department was so impressed with the design of the home that he granted a variance and gave the project his blessing.

A few months ago, another variance was sought with a new building department chief: using basalt rebar instead of steel for reinforcement. It is believed this will be the first permitted home in the country to use basalt products instead of steel. The basalt bars are 20 percent the weight of steel and have more than twice the tensile strength. They are also non-corrosive and nonconductive.

The home will be totally different from the ground up: positive convective ventilation, a gutterless roof system with built-in water catchment, and the site-cast block will be made with a waterproofing agent in the mix as well as color. When the block are installed and grouted, they will require no further surface treatment. The home will look like an Asian temple with an interior courtyard. It will also serve as a model for all those builders and architects who want to see and feel something new.

But Hollowstone is not stopping there. A system using stay-in-place basalt forms for curvilinear roof systems is in the works. (The downside of most concrete building systems is using stick-frame format for roofs.) The forms will be light enough for one person to set in place. Next year, Hollowstone will introduce a truly 3-D interlocking concrete terracing unit, Interock, which is designed for structurally engineered non-mortared retaining walls. No other system can make this claim. Plus, each unit will only weigh 40 lb., so one person can set them in place. They can do straight or curved walls.

Currently, Hollowstone is engaged in making prototype molds for the block system, then have them mass produced. The company is also creating its own model for business structure, while looking for additional investment capital to speed things along. Hollowstone is seeking a total of 12 investors, but only taking verbal commitments until all 12 slots are filled. Investors will receive dividends upon point of sale.

Through the GeckoStone website (www.geckostone.com), homeowners and developers from around the world—yet to find a concrete building system they are satisfied with—have expressed interest in Hollowstone. The block wall concept addresses a niche for a system that is simple to use, strong and adaptable to almost any architectural model. Besides offering DIY block molds, the company will also market a variety of related admixtures, basalt products, and cellular concrete technology—a one-stop shop for concrete products.

So far, the company has several investment commitments. Randall Prouty, CEO of World Associates, Inc. states, “Our company plans to use the block system in our model sustainable project, Yellow Hills Ranch, located in New Mexico. We agreed with Hollowstone’s approach to building after investigating every system we could find, none of which met our specifications. The system requires simple skills and uses readily available materials onsite. We believe it will deliver superior performance as it relates to cost, ease of use, strength, and is a platform for creating passive buildings, residential or commercial.

“These combined traits met several key requirements that were unavailable with any other system we considered. During the process, we realized the Hollowstone system has potential for use in the larger commercial market as well, leading us to consider how to promote its use more widely as a commercial venture.”

Adds another investor, John Lyle, “The Hollowstone concept is way ahead of the curve and will make a huge impact on the construction industry as well as benefit the individual builder.”

The concrete industry needs a wake-up call. There’s a huge void worldwide, especially 20 degrees north and south of the equator, where the majority of homes are built using masonry due to deforestation and tradition. Hollowstone seeks to fill that void.


Author John August is an inventor, writer, architectural designer, and cellular concrete consultant. He can be reached in Hawaii at 808/315-8743.