Innerspace Storage Corp. operates a publicly bonded warehouse developed in an underground limestone mine. Situated near Sugar Creek, Mo., a suburb of Kansas City, the mine is in a geological region known as the Bethany limestone ledge. Unlike ledges in other areas that have tilted through the movement of the earth, the Bethany ledge is horizontal, allowing for the creation of a level floor and rooflines.
Mining started in the early 1960s in response to the demand for limestone aggregate. "The property was originally owned and mined by my father's companies," says Mark Roberts, president of Innerspace. As the rock was removed and sold, space became available for development.
Several characteristics of the mine were important for its later manifestation as a storage facility. The limestone ledge is 20 to 22 feet thick, which allows for a 6- to 8-foot ceiling after mining out 14 feet. Because the ledge is near the surface, removal of the hillside provided easy access to the facility. A 4-foot shale ledge above the limestone ledge prevents moisture from penetrating to the layer below, keeping the storage area dry.
In the mining process, a pattern of pillars--20 feet by 20 feet every 50 feet apart--was used to support the roof. Eventually, more than 7 million square feet of space, not counting pillar space, was mined out, creating a natural shell building. The development of storage space mainly consisted of removing 3 feet of shell below the limestone ledge to create 17 feet of building height, more than enough to accommodate large RVs. Additional finish involved pouring concrete floors, putting up block walls, whitewashing rock surfaces and adding lighting to the ceiling.
Innerspace started storing units in 1975 and has expanded to 400,000 square feet for RV, boat and auto storage and 100,000 square feet for commercial storage. The vehicle storage can accommodate more than 1,400 units of various sizes, ranging from single wave runners to 45-foot motorhomes.
"Our facility naturally stays 60 degrees year round and offers protection from extreme temperatures of heat and freezing," Roberts says. Dehumidifiers ensure the moisture content of the caves remains low. Also, there are no ultraviolate rays or worries from storm damage such as hail, tornados, rain or snow. Although busy year round, demand for storage is heaviest during the winter months "because customers don't have to winterize their units saving them money," Roberts asserts.
"We use a valet-type system for storage," says Roberts. This ensures vehicles are parked safely. "The customer drops off his unit outside the facility in the parking lot, and it is placed and parked by our staff." The customer is issued a warehouse receipt for his vehicle. When a customer wants to pick it up again, he notifies Innerspace staff, and it is brought outside for pickup. Clients can visit their vehicles if they need to, but no one has unescorted access to the underground facility, Roberts says. An employee accompanys a client to his space. If he needs access to his vehicle for more than a few minutes, it is pulled out and parked in the lot.
How do customers feel about storing a $100,000 or $300,000 RV underground? "I have a very dependable, trained staff of six people who use extra care in the handling of the units," Roberts says. "Our business relationship has developed on trust, built on our reputation. We have made satisfying customers the primary means of marketing our facility."
For more information, call 816.257.5252 or visit www.innerspacestorage.com.