In-tents discussion: today's tents offer more flexibility, require expert design and installation.

Managers of clubs and resorts have long recognized the value of tents as solutions to all kinds of issues: outdoor bars, hospitality suites for tournaments, temporary replacements for space under renovation, extra ballrooms or dining rooms when space is in demand, or fallback shelters in case of inclement weather for outdoor events.

Anyone who has attended the various hospitality shows recently has seen that the tent industry's products have evolved incredibly over the years. Today's tents range from simple pop-up structures to massive, engineered affairs. As the industry has grown--and as safety issues of event venues have been more and more in the public eye--tents have also caught the attention of code and safety officials.

"More and more tentage is being used, in quantity, size, and length of setup," said Kurt Warner, president of Warner Shelters. Now, the people having jurisdiction over structures going up are made aware that a tent is going up. Not only are building permits having to be drawn--in some instances a development permit may have to be drawn."

Because of these and other issues, if you're considering a tent for a temporary or long-term solution, it pays to have an expert on your side. The size of the tent, the length that it is to stay in place, whether you're going to heat and cool it, safety issues, and many other factors must be taken into consideration.

A central source for information on tents is the Tent Rental Division of the Industrial Fabrics Association IFAI, www.tentexperts.com), an industry group representing tent manufacturing, sales, and rental companies. The following information is from that site's frequently asked questions:

What is a tent? According to a glossary of tent terms published by the Tent Rental Division of the IFAI, a tent can be defined as a temporary structure composed of a covering made of pliable material or fabric, that is supported by mechanical means such as poles, metal frames, beams, columns, arches, ropes, and/or cables.

Is it better to buy or rent a tent? The decision to buy or rent a tent has many variables. If the tent will be used for three or four times each year, it is probably better to rent the tent. The experts in your area will be better prepared with the necessary training and expertise to safely install the tent. Professionals also have the tools, washing facilities, and storage areas to maintain the tent when it is not in use. Your local rental professional often has long-standing relationships with the fire marshal, code enforcement officials, and other regulatory officials, which can make renting the preferred choice. Renting will also allow you to vary the color or size of tent according to your specific needs. Of course, if you will be using the tent frequently or for long periods of time, it may be wise to purchase a tent.

What size tent is necessary for your special event? A person must first determine tent usage. If a tent is being used for dining purposes and round tables are being used, allow 10-12 square feet per person. If banquet style tables are being used allow 8-10 square feet per person. If cathedral-type seating is being used, and there are rows of chairs, allow six square feet per person. If aisles and a speaker area are also needed, allow eight square feet per person. If the purpose is for cocktail service, allow five to six square feet per person.

Somebody who knows as much about tents as anybody in the business is John Schlueter, president of Karl's Event Rental in Milwaukee, WI (www.karls.com, 1-866-EVENT88). He has been in the tent business for over two decades, planning tents used in events for clients including Lincoln/Mercury, Sony, DirectTV, the National Football League, and the White House. When Schlueter was interviewed for this article, two of his employees had just returned from Kuwait, where they had just supervised the erection of 75-by-200-foot tents for the military, each capable of feeding 8,000 military personnel per day.

Schlueter said that today's tents can be as small as nine by 10 feet, and as large as 164 feet wide by any length imaginable. He explained that tents today come in three basic types which represent the evolution in tent technology. The first is the grandfather of the tent business, the familiar pole tent. Pole tents are the old "big top" used in circus events, with a center pole and perimeter poles held in place by lines roped to stakes. They range in width from 10 feet to 100 feet. Their advantage is that they are inexpensive for small events. Their disadvantages include the center pole, the stakes (which can destroy tennis courts, parking lots, etc.), and their relatively low perimeter height of seven to 10 feet.

The pipe frame tent, as its name implies, is supported by a framework of one-inch pipe. Its advantages are that there is no center pole and that the pipe frame--while it can be anchored with ropes and stakes--can also be ballasted with concrete blocks or water barrels. Its two disadvantages are that it maxes out in width at about 40 feet and--similar to the pole tent--it has relatively low perimeter heights (seven to nine feet).

The latest generation, Schlueter stated, is the clearspan tent. According to IFAI, a clearspan tent is defined as "a type of tent that features an assembled framework of box beam (or I-beam) arches that support the fabric roof and define the shape of the structure in much the same way as a pipe frame-supported tent. The stronger construction of the aluminum or steelbox-beam frame makes these tents suitable for larger or longer-term applications than other types of tents. The box-beam framework also allows for large areas of unobstructed `clear span' space beneath the fabric roof."

Clearspan can be easily weighted rather than staked on the perimeter, and has much higher ceiling heights, Schlueter said. "You have a lot headroom. Tents that are a few years old are at eight feet, but we're normally at 11 feet, and starting at 100 feet wide, the lowest point in a structure is 13 feet. It doesn't sound like that big a deal, but if you've ever sat in a ballroom where the ceiling's too low, you'll know the difference."

The clearspan structures are made to stand up to wind and weather: "The tents that we're carrying will withstand 70 mph wind," Schlueter said. He said that the material used on clearspans is different from other types of tents in that it is heavier (22-ounce vinyl versus 16-ounce on pipe and pole tents) and much smoother, which means it stays clean longer.

Clearspan structures are also more flexible than pole and pipe frame tents in terms of location. "We've put them them on rooftop decks," Schlueter said. "We've put them in a park in New York with one foot of clearance all around. We've put them up over trees 20 feet tall and over short parking lot lights."

Once the tent is in place, the weather can be kept out by the use of side panels, which can create a very tight seal. The panels typically have a length of flexible, round material called keder (pronounced KEEDER) wrapped and stitched along the edges of the fabric. The keder slides into a rounded "keder channel" attached to the tent frame, thus creating the seal.

At this point the tent very much begins to resemble a building, and putting one up is definitely not a do-it-yourself project. "Even though a lot of our people have been here for 15 years, they go to training schools all the time," Schlueter said.

Schlueter said that Karl's erected tents in 35 states in 2002, and that while there are some differences, the basics of what local officials are looking for remains fairly constant. Schlueter said that his company will provide drawings of the structure sealed by an engineer for structural integrity. Beyond that, "they're looking for emergency exits." Today's tents, he said, can provide everything from Velcro breakaway tent panels to full glass commercial double doors with hydraulic closers.

On larger tents--particularly for longer rentals--you should install a safety package including lit exit signs with battery backup and floodlights, fire extinguishers, and no "smoking signs," Schlueter said.

The complexity of erecting today's event tents tends to load costs on the front end, Schlueter stated. That makes a good argument for getting as much use out of the structure as your property can once it's in place. "Because of what's involved in installation, longer terms really do reduce the costs of rentals," he said.