Texas Tilt Up Construction - Excellence in Concrete Construction

In traditional forms of wall construction, the walls can be built with CMU blocks or blocks faced with brick. For some types of buildings, the exterior wall is made up of structural steel columns with heavy gauge metal studs covered with gyp sheathing, which is then faced with brick or stucco. Regardless which traditional approach is used, building the exterior walls happens from the ground up, and is a time-consuming, multi-stepped process.

A tilt-up building's walls are created horizontally in a high tech version of the old 19th century barn-raising. Workers lay out wood forms on the project's floor slab and set up grids of rebar inside each form. They then pour concrete into the form and, when they dry (or cure), remove the forms to leave large slabs of concrete called panels. The panels are then lifted, or "tilted up," into position around the building's slab and braced for safety until the panels are connected and secured permanently into the ground. Each panel weighs many tons, to a large crane is required to stand the panels into place.

As you can imagine, in a tilt-up building the walls are essentially finished once the panels are stood. Roofing crews can start placing the steel very quickly, and the other trades can get inside and start to do their work - it's not uncommon for these crews to be working on one end of a building even as the concrete crews are still standing panels at the other end. This overlapping of disciplines is another reason why tilt-up is such a fast method of concrete construction compared to traditional methods.

Look below for photos that show the tilt-up construction process.

The basic principle behind tilt-up construction - constructing walls horizontally, on the ground, and then lifting them into place - is not a new idea. Evidence exists that some buildings constructed during the Roman Empire and builders during the Middle Ages used this approach.

More recently, American settlers in the 1800s gathered for "barn raisings" where they constructed the wood walls for their buildings and tipped them up into place. Even with the limited raw material of wood, 19th century Americans were able to construct two story barns and houses very quickly using this approach. So effective was this approach that rural builders used this technique well into the 20th century, as shown in the photograph to the right*.

The 20th century marked the true beginnings of modern tilt-up construction. The development of concrete reinforced with rebar in the early 1900s allows builders to create tilt-up commercial structures as we think of them today: One- to two-story structures built with walls comparable in width to those created with other methods of construction.

Even with this innovation, tilt-up construction did not gain wide acceptance until after World War II, when the mobile crane was first developed. The mobile crane allowed builders far greater ability to lift the massive panels into place, regardless where the job site happened to be. At about this time, ready-mix concrete was introduced to the industry, making tilt-up an even more viable alternative.

These new technologies occurred at precisely the right time. The late 1940s brought about a post-war boom in the construction of manufacturing and industrial facilities across the United States. Innovation, timing, and the need for large, warehouse-styled buildings opened the door for tilt-up construction. The three factors combined to encourage general contractors to embrace tilt-up as an economical means of delivering quality projects that meet even the most demanding specifications and schedules.

Over the years, industry experts have continued to refine and enhance the tilt-up process, allowing general contractors and design-build construction managers to drive greater capabilities and creativity in its use. In 1986 the Tilt-up Concrete Association (TCA) was created to establish processes and standards to ensure continued growth in quality and acceptance for this method of construction.

Tilt-up concrete construction has since been used in buildings as large as 1.7 million square feet, with individual panels reaching as high as 91 feet and weighing 150 tons. The TCA reports that 15% of all industrial buildings in the U.S. were created using tilt-up construction. It is growing at an annual rate of almost 20% and is used in over 650 million square feet of new building construction each year. In Texas and other sunbelt states, tilt-up accounts for as much as 75% of new one-story commercial building construction. General contractors, design build contractors and builders in Mexico, Canada and Australia are also using tilt-up concrete construction on an increasingly frequent basis.

* Photo courtesy of the Farm Security Administration - Office of War Information Photograph Collection: Library of Congress Prints and Photographs Division Washington, DC.

Several terms - tilt-up panel construction, tiltwall construction, precast concrete building construction - are used to reference new or nontraditional cement building processes. Do they all mean the same thing? If not, what are the differences?

Tilt-up and tiltwall are two terms used to describe the same process. Different parts of the country use each term, and many people use the terms interchangeably.

For a tilt-up concrete building, the walls are created by assembling forms and pouring large slabs of cement called panels directly at the job site. The cement panels are then tilted up into position around the building's slab to form the walls. Because the concrete tiltwall forms are assembled and poured directly at the job site, no transportation of panels is required. One major benefit of this is that the size of the panels is limited only by the needs of the building and the strength of the concrete panels themselves.

Tilt-up construction panels can sometimes be extremely wide and/or tall. Tilt-up concrete panels have been measured at just over 69 feet across and almost 93 feet from top to bottom. Thus, architects and tilt-up concrete contractors have a great deal of flexibility in planning and creating their buildings.

Because concrete tilt-up walls are poured outdoors, contractors are at the mercy of climatic conditions. When temperatures drop below freezing, curing the concrete panels becomes more difficult and expensive. This is why tilt-up concrete construction is particularly popular in Texas and southern parts of the United States, where cold weather occurs less frequently. Certainly, tilt-up concrete buildings are built in northern areas, but the window of time for temperate weather is much smaller and less predictable, which can make construction schedules more difficult to meet.

The precast concrete building process is similar to tilt-up construction, but it addresses the challenges presented by weather. For precast concrete buildings, work crews do not set up forms at the job site to create the panels. Instead, workers pre cast concrete panels at a large manufacturing facility. Because the precast concrete forms are poured indoors, this activity can take place regardless the weather conditions. After curing, the precast concrete panels are trucked to the job site. From this point, precast concrete buildings are assembled in much the same manner as tiltwall buildings.

The fact that precast concrete walls are formed at a manufacturing facility resolves the weather issue, but presents a different limitation not found in tilt-up construction. Because the panels must be transported - sometimes over long distances - this places a substantial limitation on how wide or tall each panel can be. It would be impossible to load precast panels that were 60 feet wide or 90 feet long onto trucks and transport them any distance. For a precast construction project, the panels must be smaller and more manageable to allow trucks to haul them over the road to their final destination. This places greater design restrictions on architects and limits the applications where precast construction can be used.

Clearly, tilt-up (or tiltwall) concrete construction and precast concrete are similar processes. Because tilt-up affords more flexibility, it is the method of choice in locations where the weather allows it. Precast concrete is a suitable choice in circumstances where environmental factors and the construction schedule preclude tilt-up as a viable option.

An important fact to remember is that the use of steel in building is not necessarily exclusive of concrete or blocks. In larger or more sophisticated projects the different raw materials and construction methods are frequently used together.

Here are some very common examples of how steel, concrete and tilt-up construction are used together to provide the best quality and value:

A large steel office building or retail center may use tilt-up concrete panels for interior fire walls or exterior facades. The Mervyn's retail store in Dallas / Fort Worth, Texas pictured to the right was constructed in just this manner.

An existing manufacturing building or warehouse made of concrete blocks could be expanded by adding a steel lean-to structure to one of its exterior support walls.

A distribution center built using the cement blocks of traditional construction will frequently use a steel roofing system and a rigid frame similar to what a metal building might use. Regardless what material is used, this combination of a rigid frame and steel roof is necessary to provide a large clearspan.

These are just a few situations where the best choice for a project might be a steel building with tilt-up construction components, or a concrete structure with steel framework, roof system or steel add-ons or expansions. A general contractor who is well versed in the advantages and limitations of all methods of construction can help determine what is the best approach on any given project. Visit our Construction Links page for general contractors and construction managers who are experienced in tilt-up construction.

The key to successful commercial construction is balancing quality with cost and schedule. While this is always a challenge, external forces like local building codes often make the balance even more difficult to achieve.

Such was the case with Northern Tool & Equipment Company's retail store in Lewisville, Texas.

Our construction team decided this would be a tilt-up construction building very early in the design process. Tilt-up construction provided substantial cost savings and made the proposed building schedule much more feasible than a traditional CMA concrete building would allow for. Steel buildings were competitive in cost and schedule to tilt-up, but local zoning did not allow for metal structures in this location and the client wanted the superior quality of a concrete building. Tilt-up was clearly the construction method of choice.

When the decision was made, however, another issue arose. Local building codes required new commercial buildings to have 100% masonry façades. We had built a Northern Tool and Equipment retail store the year before in Grand Prairie, Texas and we finished that with paint. We couldn't do this in Lewisville, however, because local codes required a masonry finish to the building.

In previous years the alternative would have been to build a masonry façade along the walls' exteriors. This would have driven up construction costs and added crucial days to the schedule, all but erasing the benefits of tilt-up construction.

We had to come up with a more innovative solution.

The solution was found in a product from Scott System called Brick Snap. This product allowed construction crews to attach a brick wall façade to the tilt-up construction panels as the panels were cast rather than constructing a façade in a separate step after the walls were cast and stood.

To use the Brick Snap system, workers placed individual masonry tiles connected by plastic trays into the tilt-up construction panel forms. The tiles, coated in wax to ensure their faces didn't stick to the concrete, form the walls' bricks while the trays define the mortar pattern between the bricks.

Once the work crews set up the tiles and trays, they poured the concrete into the forms to create the tilt-up panels and allowed them to cure, then stood and secured the panels to form the walls. Workers then washed the walls' exteriors with warm water to remove the trays and wax and leave the masonry tiles in the finished brick pattern.

The Brick Snap system worked - the project satisfied the city's requirements while maintaining the cost and speed advantages that tilt-up construction provides.

The Brick Snap system is another example of how the construction industry is driving innovations to manage costs and schedule without undercutting quality - the key benefits of tilt-up concrete construction. As these creative solutions are improved and implemented, tilt-up construction will continue to evolve into the construction methodology of choice for an ever-growing circle of commercial building applications.

More information on this tilt-up construction project in Texas.