Forms

A spate of fires in Montana several years ago inspired Stewart Hansen to find a way he could build homes with all the character of traditional log homes, and all the fire-resistance of concrete.

The solution was to develop concrete log homes, which his company, Missoula-based Concrete Logs LLC, is now doing successfully into its fourth year.

With 30 concrete log homes on the market, Hansen said the company is now developing between 10 and 15 new concrete log homes each year.

Concrete Logs LLC sells just the exterior wall system, not the entire house, and charges between $70 and $80 per square foot. Finished turnkey costs can run anywhere from $130 to $500 per square foot depending on the customer’s preferences.

Using forms cast from actual wood logs, Concrete Logs LLC has also placed a premium on energy efficiency in its homes. Hansen said a recent test conducted by the National Center of Appropriate Technology indicated Concrete Log homes are seven times as airtight as traditional wood-log buildings and six times as airtight as traditional wood-frame buildings. A recent 10,000-square-foot custom home in Colorado has monthly utility bills of $322 per month, he said.

ArroDesign of Waitsfield, Vermont, recently completed construction on an all-concrete tree house.

In addition to traditional cardboard tubes, ArroDesign employed Fast-Tube column forms. Manufactured from high-strength fabric, Fast-Tube comes on rolls of 60 and 120 feet, and in diameters ranging from eight to 24 inches.

“We were able to pour 29-foot columns with a single form and obtained a beautiful textured finish,” says Sandy Lawton, president of ArroDesign.

To join the tree house with the main residence, the crew created a suspended, curved concrete walkway using both conventional forms and Fast-Tube column forms.

Sonoco has announced plans to market its concrete column forms in a retail-type environment through licensed distributors.

The company plans to create point-of-purchase displays for use in as many as 300 specialty distributor locations throughout the United States.

“This idea was a direct offshoot of a lot of the big box stores and Home Depots and Lowe’s increasing having quite a purchase display for regular customers,” said Mary Ruth Austin, an internal media specialist at Sonoco. “As other concrete stores and other home improvement stores are adopting that approach, the thinking was that this was a unique way to market this, and to help these folks as they turn what used to be a warehouse environment into a retail environment.”

Products included in the promotion are the Sonotube round, Sonotube Finish Free, Sonotube square, Sonotube Commercial and Sonotube TubeBase forms.

The displays feature textured vac-form 3-D column simulations, sectioned product samples and a raised letter logo panel on a 28-inch tube base and support tube. The 3-D simulations show contractors what finished columns will look like before they buy or pour anything. The displays also are designed so that the riser can be easily hung on walls for distributors that may not have the floor space for the entire unit.

“The thinking was that, for the contractors and the subs would be purchasing this, it would make the environment more welcoming and it would put our product out front, rather than people just saying, ‘Do you have any Sonoco forms?’”

A Ransonville, New York-based construction worker has patented a new system for separating set concrete from forms – a system he says uses prybar-type leverage to save time and labor.

David Barto, who says he works many projects through his membership in Union Local 289, is seeking a manufacturer for the BartoBar – a concept he says he developed on a job site as he observed colleagues struggle with form removal.

“Wherever your pins go, you just set this tool into that, and it’s like a prybar, instead of going between the concrete and the form,” Barto said. “It’s safer. It works on leverage. It’s like having your foot close to the panel, and you use it to push it right off.”

Barto says his invention will reduce physical exertion needed to remove forms, thus reducing the likelihood of job-site injuries, and results in less damage to concrete and to forms.

Barto said companies interested in contracting to manufacture the product should contact him at 716.754.4491, or e-mail him at harleybart2000@verizon.net.

The National Standards Development Committee of the Portland Cement Association (PCA) has approved the first PCA standard utilizing the American National Standards Institute (ANSI) accredited voluntary consensus process.

The new standard, PCA 100-07, “Prescriptive Method for Design and Construction of Residential Concrete Walls”, facilitates the use of cast-in-place concrete wall systems built with either removable or stay-in-place forms, such as insulating concrete forms (ICFs). It applies to the construction of detached one-and-two family dwellings.

PCA 100-07 provides a simplified approach for the design and construction of cast-in-place concrete foundation and above-grade exterior walls. It is based on the requirements of ASCE 7-05, “Minimum Design Loads for Buildings and Other Structures”, ACI 318-05, “Building Code Requirements for Structural Concrete” and test results.

PCA anticipates that the standard will be referenced in the 2009 edition of the “International Residential Code for One-and-Two Family Dwellings” (IRC), and will be available from PCA by the end of the year.

Omaha-based Reward Wall Systems has announced its application for a patent on a new corner bracket designed to add strength to insulating concrete forms.

Reward Wall Systems has applied for a patent on a full-height, double-H bridging corner bracket designed to enhance block performance by enhancing strength during concrete pours.

“The new Reward corner pushes ICF corner block performance to a new level,” said Hank Pfeiffer, chief operating officer of Reward Wall Systems. “The product provides additional furring for the attachment of external and internal finishes. Having more corner attachment options will really increase the user-friendliness of ICF corner blocks.”

Reward Wall Systems expects the product to be available by September. Production began in July at the company’s manufacturing facilities in Rockford, Minnesota and Nixa, Missouri.

In early June insulating concrete form manufacturer Amvic Building System, Toronto, will release a 12 inch ICF that will be 17 inches wide x 24 inches high x 48 inches long. It will be available in a straight form which will cover 8 square feet and in a 90 degree form which will cover 9.83 square feet. The forms are manufactured using 2.5 inches of 1.5lb/cf density EPS foam on each side. The panels are rigid, therefore maintain shape, remain straight and plumb and require less bracing during concrete pouring and curing. The Canadian Construction Material Center (CCMC) has measured the form’s forming capacity strength test at 865 pounds per square foot.

Cement industry associations have agreed to provide insulated cement-based wall panels for the U.S. Air Force Air Force Research Laboratory (AFRL), at Tyndall Air Force Base, Florida, to test the blast-resistance of different concrete building systems.

Included in this research scope are several double wythe insulated masonry wall systems (NCMA and Brick Industry Association - BIA), two precast/prestressed sandwich panel systems (PCI), two tilt-up concrete sandwich panels (TCA), three different insulating concrete form wall systems (ICFA) and an exterior insulated cast-in-place wall (CHC). Predictive analytical models, laboratory testing and full-scale explosive experiments are the primary research components.

Through this study, they hope to be able to predict the blast response of these COTS wall systems for both new construction and retrofit structures. The research program will comprise three phases. The first phase will examine existing COTS insulated cement-based wall systems, designed with standard mix concrete to meet a specified wind load and seismic design. The second phase will examine several unique concrete wall systems. The third phase will look at any modifications that could significantly enhance the blast performance of phase one and two products.

The research began in 2006 with the evaluation of 30-foot precast/prestressed insulated sandwich panels. Although, the blast effects are still being analyzed, the damage observed appeared minimal. The next wall assembly test scheduled in 2007 will be the reinforced masonry systems. A third wall assembly planned later in 2007 will be either an insulated tilt-up sandwich panel wall or one of the three ICF wall systems.

Quad-Lock Building Systems Ltd. released a new promotional video, “SAFE-R, The Solution for Residential Construction,” targeting homeowners looking to build a concrete home. The twelve-minute video details why building and living in a concrete home is more comfortable, energy efficient and safer than living in homes built with other materials. In addition to the video, product brochures, a photo gallery, both video and written testimonials as well as a time-enhanced video clip are available on the DVD.