The Engineering Behind the Tella Firma System
Tella Firma Foundations make use of either concrete or steel helical piers and may also work with spread footings to carry the load of the structure below the active zone to the structurally stable soil beneath the surface.
Fewer Piers with a Thinner Slab, No Interior Beams, Less Concrete
This technology requires a fewer number of piers than traditional slabs. Tella Firma slabs are designed as a “flat plate,” typically five inches thick. The slabs do not require interior or stiffener beams—like traditional “waffle slabs”—only a shallow beam around the perimeter. As a result, Tella Firma designs require approximately 30 percent less concrete.
See how we’re building a more solid foundation for companies across the country
‘’Light Design’’ Principles Lead to Lighter Costs
Traditional slab-on-carton-form foundations use “heavy design,” relying on heavy, drilled concrete piers and a thick slab to span the increased space. Tella Firma harnesses the principles of “light design.” This makes use of steel helical piers, which are significantly more cost-effective than 18” or 24” concrete piers. A larger number of helical piers enables reduction in the pier spacing and allows for a much thinner slab to achieve the strength necessary to span the piers.
Thinking Outside of Old-Fashioned Carton Forms
Tella Firma eliminates the need for expensive and weather-prone carton forms—essentially, cardboard boxes used to create subfloor void spaces. These traditional void forms often get wet from rain or absorb humidity from the air, resulting in a collapse when concrete is poured. Conversely, if the carton forms are too strong and do not decompose over time, they may not collapse as soil expansion occurs, resulting in movement or damage to the floor slab. The Tella Firma system elevates the slab with lifting mechanisms, eliminating the need for problematic carton forms.
Easing the Burden of the Slab
In all commercial foundation designs, heavy structural piers must be located under the heavy point loads. In the Tella Firma design, a leave-out is located in the slab over the structural pier. The load-bearing column is attached directly to the pier and the slab is lifted independently, so the slab never has to carry the heavy structural load.
Raising the Bar Using Post-tension Reinforcement
Tella Firma foundations can be implemented with either traditional rebar or post-tension cable. However, the greatest savings are realized by making innovative and economical use of post-tension (PT) design reinforcement. The PT cables are profiled or draped up or down within the slab to place the reinforcement where it is most needed. Once the slab is poured on top of the ground and the PT cables have been stressed, it is then raised above the ground to a desired height with Tella Firma patented lifting mechanisms. The process of using the ground as a form is very economical, much like commercial tilt-up wall construction. After the lifting process is completed, a protective cap is placed over the lifting mechanism and left embedded inside the slab. This allows access to the mechanism should future adjustment of the foundation be required.
Frequently Asked Questions
about Tella Firma Commercial Foundations
What is a Tella Firma foundation?
ANSWER: The Tella Firma foundation is an innovative and patented system that provides all the benefits of a pier-and-beam or other suspended foundation system, yet is much more affordable, and takes less time to install when compared to most traditionally-suspended foundations. The patented foundation system was created in an effort to prevent costly foundation damage by withstanding the notorious volatility of active clay soil and gives the structure a foundation that can be trusted.
Does the Tella Firma Foundation System save costs?
ANSWER: Yes, Tella Firma foundations are a more affordable alternative to other commercial-grade suspended foundations, such as a suspended slab using piers and carton forms, or a foundation crawl space. Using the Tella Firma system has saved commercial owners hundreds of thousands of dollars.
Are Tella Firma foundations available regionally or throughout the country?
ANSWER: Tella Firma foundations are most commonly found throughout Texas, Louisiana, and Colorado, but are applicable throughout the country wherever soil movement is found. If you’re interested in a Tella Firma foundation in your area, please contact us.
Why is the company called Tella Firma?
ANSWER: “Tella” is Latin for castle or structure, as in “a person’s home is their castle,” and “Firma” is Latin for solid or stable, so the name stands for solid or stable home or structure.
When did Tella Firma begin?
ANSWER: Tella Firma Foundations began in 2015. The foundation system itself has been used with great success in homes throughout North Texas beginning in 2005 and using commercial engineering principles that have been in practice for over 50 years.