The concept of lightweight yet strong structures using membranes stretched over a framework isn’t new. For millennia, yurts and teepees were built this way.
The same principles that made those structures successful have a modern expression in engineered fabric buildings.
Today’s engineered fabric buildings reliably house industrial projects, athletic facilities, and entertainment centers, and offer a number of unique advantages over conventional steel and concrete buildings for both temporary and permanent installations.
Below are the top five facts you need to know about what makes fabric buildings superior to steel and concrete buildings.
#1 - Intelligent Engineering for Fabric Buildings Allows for Diverse Applications
To house industrial equipment, aerospace projects, mining operations and more, customization is key.
Fabric buildings can be constructed to meet diverse dimensions, including varying roof pitches and peak heights. They can even be uniquely shaped for odd-sized lots.
Legacy Building Solutions, a supplier of engineered fabric buildings, takes pride in their ability to deliver uniquely customized buildings.
“We’re not a building-in-a-box kind of supplier,” said Dwayne Moench, senior structural engineer at Legacy.
“The IEI Barge project in northwestern Illinois,” Moench explained, “is an excellent example of a building with diverse dimensions to accommodate lean-tos, a conveyor, an offset peak, varying column-heights and geographical fit along the edges of a river. Highly customized buildings like that aren’t very challenging for us, it’s our strength.”
IEI Barge fertilizer potash port terminal. (Image courtest Legacy Building Solutions.)
Some fabric buildings have been developed with widths of over 300 feet and lengths of 1000 feet. Like with the IEI Barge structures developed by Legacy, rigid steel frames can be customized to include offset peaks, varying column heights, canopies, lean-tos and mono-slope roofs.
Steel frames in fabric buildings can also be designed to support additional structural elements such as hangar doors, fire suppression systems, cranes and conveyors, heating or cooling systems and heavy lighting equipment.
#2 – Fabric Buildings Are Highly Durable
The rigid steel frame is the same one used for decades in all types of building construction. The ripstop fabric will last for multiple decades, giving fabric buildings the strength and durability required for heavy industrial use.
Rigid frame designs can allow fabric buildings to support additional loads on the structure, such as conveyors and cranes, while exceeding local building codes related to wind, snow, and seismic activity.
“The largest we’ve designed, and it’s currently shipping, is 230 ft. wide by 980 ft. long, going to Sierra Leone, Africa,” said Ben Fox, president of Legacy. “The building will be covering iron ore in a very wet area as they have extreme rain seasons, a fair amount of wind and a very hot climate.”
To help the building stay clean in the event of humid and rainy weather over extended periods, fabric buildings like this one, use fungicide-resistant fabrics to prevent the growth of molds and their resultant damage.
“For another example of fabric building durability, a couple of years ago, we shipped a 12 ft. by 30 ft. fabric building to house a vibrating table at a mine in northern British Columbia,” Fox described. “They needed a tough building that could handle the shaker table’s vibration. For a typical all metal building, it wouldn’t take long for all the screws to shake out of the roof and wall panels.”
“As it was housing a shaker table, any movement at all sent the snow sliding off the roof because our material provides a very slippery surface,” Moench added. “We still have to design for the combination of seismic and snow loads, but the reality is it’s far less of an issue as the snow will slide off a shaking fabric building very quickly.”
Snowfall is also a particularly significant issue, the 20 meter by 25 meter Los Bronces fabric building in Chile is designed to withstand the harsh conditions of the Andes mountains including up to 246 pounds per square foot of snow on its roof.
Fabric buildings do not require screws or nails along the roof, preventing any entry points for moisture, which causes rust or corrosion. The steel support beams and trusses used in fabric structures are usually hot dip galvanized to further protect against rust. And of course, the fabric itself is immune to the effects of corrosion.
Architectural fabric is made to outlast other building materials. Flame-retardant fabric is available. The fabric also contains a UV-resistant material to protect from the sun’s rays.
In a situation where repairs are necessary, repair costs can be as low as USD$2 per square foot. Replacement steel can cost up to USD$7 dollars per square foot.
#3 – Fabric Buildings Are Energy Efficient
Costs normally associated with heating and cooling a steel and concrete building are significantly lower with fabric buildings.
Because the fabric materials are naturally non-conductive, the interior of a fabric building will remain cooler on hot days and remain warmer on cooler days. The fabric does not retain heat from the sun, instead maintaining the interior temperature better.
“Before installation of HVAC systems, fabric buildings will stay up to 5 degrees warmer on colder days and almost 10 degrees cooler on most hot days,” said Fox.
Fabric roofs also offer up to 12 percent translucency to allow natural light to permeate through the structure, eliminating the need for artificial lights during the day. To further offset energy costs, solar panels can be included in a fabric building design.
#4 – Fabric Buildings Are Easy to Set Up and Relocate on Various Foundations
Fabric buildings can usually be installed three times faster than conventional structures. They are usually permanent, though they can be designed as portable. Flexible fabric is easy to roll up and move to a new location as needed.
Most fabric buildings require .02 to .03 man hours per square foot to be installed, compared to steel sheeting which requires .04 to .07 man hours per square foot.
“When considering the fabric membrane only, the install time is .01 man hours per square foot when compared to .03 man hours per square foot for steel sheeting systems,” said Fox. “The cladding is where the majority of the install efficiency is gained. It is far faster and safer to install fabric cladding over steel systems. A typical standard fabric structure can be dismantled in .015 man-hours per square foot.”
A common misconception concerning fabric buildings is that they must adhere to different architectural codes and loadings than traditional metal buildings. The truth is, the same engineering used by the metal building industry is also used by fabric building designers.
“Overall the reactions from the rigid frame supporting a fabric structure are identical to standard metal building reactions,” said Moench. “Expectations for foundations should be the same for both types of buildings as they use the same wind, snow and seismic loads. Some fabric building suppliers claim that little or no foundations are required, but that should be a red flag that they are not applying their loads accurately.”
Fabric buildings can be installed on a range of foundations including screw piles, helicals and precast or cast-in-place concrete.
#5 – Fabric Buildings Are Sustainable and Recyclable
Most of the materials in a fabric building can be re-used.
“Many fabric buildings contain recycled materials and can be recycled again after use,” Fox said. “Some fabric manufacturers work with outside recyclers to process used membranes for use in new products.”
When a fabric reaches the end of its life cycle, the manufacturer can assist the customer in finding a partner to effectively recycle the fabric membrane.
“Most of our fabrics will last in excess of 20 years,” Fox said. “Most of our good quality PVC fabrics will last in excess of 30 years, and even at the end of that life cycle, they are recyclable. It’s no different than a steel building – if it corrodes out in 20 years, they’ll put a new steel roof on it, it’s the same with fabric.
An end user would consider reskinning a fabric building similarly to reroofing conventional buildings.
“In reality, reskinning a fabric building is going to cost significantly less than reskinning a steel building, just by the nature of the labor savings,” Fox said. “The process is also much simpler, as it can sometimes take a fourth of the time of the original construction of the fabric building.”
In addition, the polyethylene fabrics used in fabric structures are considered a low toxin-emitting building material.
For more information about fabric buildings and custom designs, visit www.legacybuildingsolutions.com.
Legacy Building Solutions has sponsored this post. It had no editorial input into this post. All opinions are mine. --Kagan Pittman