Tech Talk: Basement of the Year
By: Ed Sauter
Editor's note: As part of our partnership with the Concrete Foundations Association (CFA), the following article is the fifth in a yearlong series on the basics of concrete foundation construction. For more information, see www.cfawalls.org or call 319-895-6940.
One of the fundamental components of the American Dream is to own a home. Before purchasing or building a home, most buyers have established a wish list of elements that their new home must have. This is especially true for those embarking on a new-build project. These desires can often wreak havoc on a jobsite as members of the construction team investigate the best method for making the homeowner's dreams a reality. Today's concrete foundation professionals have responded to these increasing demands by employing inventive techniques and new technologies on projects.
One example is the Concrete Foundations Association (CFA) 2004 "Basement of the Year" competition (sometimes referred to as the "Basement from Hell" competition) winner. The contractor overcame rocky site conditions and a complex design, among a variety of other obstacles by utilizing technology to ensure that the homeowner's wishes were met.
The "Basement of the Year" competition enables foundation contractors to display the wide range of projects that are being completed today. The technological advancements that have been made in the poured wall industry allow contractors to complete complex projects more efficiently, which helps ensure homeowners' dreams are realized. Each year the projects submitted to the competition get more complicated and demonstrate the diversity afforded through poured wall foundations.
The winning structure is a more than 4,000-square-foot basement for a 7,000-square-foot home in Newburgh, N.Y. Although there are many projects that are bigger, the foundation boasts a circular front porch, brick ledge around the perimeter and 39 corners that are at 45-degree angles. Adding even more complexity to the project, there were a substantial variety of wall and ledge elevations.
According to Van Smith, president of Smith Bros. Concrete Contractors Inc. and the foundation contractor for the project, the other foundation contractors in the area did not even quote this project because of its degree of difficulty. "I have been in this business for more than 29 years and this is the most challenging project that I have encountered," Smith said. "The architect even commented that he did not think it was possible to do the job, which made us determined to tackle this tough project successfully."
With more than 605 lineal feet of wall, the project required 232 yards of concrete. Smith Bros. supervised the excavation to ensure that it met their requirements. Walls were formed and poured in eight days. The site made it difficult to maneuver panels around the site and the rough terrain created hardships in squaring out the job.
"It was difficult to see all the points for layout from one spot, so we had to create numerous control points to help us layout the job properly," Smith said.
To add one more challenge to this project, foundation forming occurred during the hottest two weeks of the summer with temperatures in excess of 90-degrees Fahrenheit. "With both the complexity and the temperature, we knew that we truly were constructing the 'Basement from Hell' with this project," Smith said.
Technology Aids in Success
Smith Bros. began working with the owner and architect in the fall of 2002 on the complex project. Before construction commenced, the foundation team uncovered a 4-inch error in the architect's plan that they were able to correct. Smith Bros. input the architect's print into their Trimble LM80, which made them aware of the discrepancy.
An example of the innovative technologies that foundation contractors employ, the LM80 is a layout manager construction software program that attaches to the Trimble Total Station and electronically lays out a project. This ensures precision accuracy on every project, no matter how complex. Exactness was even more critical on this project, because the layout for the excavation, footers and wall were conducted as three separate evolutions.
"This job would not have been feasible without the Total Station," Smith said. "With this technology, I am as confident in my 21-year-old son's ability to layout the project accurately as I am my own, even though I have considerably more experience than him. My crew that has been on the job for more than 25 years waits for him to arrive before beginning layout, because they recognize the tremendous value that these new technologies bring to a project."
The Total Station is an instrument that is equipped with a four-speed servo and a wireless radio link, enabling automated measuring processes. After downloading the coordinates of the plan into the instrument, the instrument locks onto the measuring pole, and tracks the user's location around the site. The instrument's wireless display tells the user which direction they need to go (in or out, left or right) in feet and inches, decimal or metric units. The display updates nearly three times per second telling the user in real-time where they are in relation to the setout point.
By downloading the coordinates directly into the machine, human error caused by incorrectly calculating the diagonal or reading the wrong dimension on the tape measure is eliminated. This equates to a time and cost savings for the builder because the foundation will more likely be poured correctly the first time. Further, projects proceed in a smoother fashion without the hassle of laying out points in difficult areas.
Looking Toward the Future
As with many industries, technological advancements are occurring rapidly in the poured wall foundation industry. One example is the robotic Total Station. This allows true one-person surveying, acting as a labor-savings tool for contractors. The robotic operation enables users to survey and stakeout on their own from the prism, further increasing productivity - ideal for both survey and stakeout work.
According to Jim Baty, technical director at the CFA, the growth in popularity of poured concrete walls over the past several decades is in large part due to the advancing technologies allowing the professional contractor to provide walls more efficiently and with greater quality control than ever before.
"As we look to the future of the industry and the continued growth of not only poured concrete walls, but also basements in general, it is evident that technology has to play an increasingly larger role," Baty said. "Changes in concrete mix designs, placement and form technology, finish options and textures and waterproofing coatings all will play a role in the growth of what is arguably the most cost-effective living space of any residence." CH
Ed Sauter is executive director of the CFA. He may be reached by calling 319-895-6940. Additional information about the CFA is available at www.cfawalls.org.