There's a new system in place for helping commercial property owners convert vacant buildings into profitable self storage facilities.

This process is called an interior self storage system or "retro" self storage - and it allows commercial property owners to transform their vacant, idle buildings into metal storage buildings.

"We've done quite a few; it's becoming a real trend for commercial property owners," said Dean Brown, president of American Steel Buildings. "If the owners have properties that are sitting empty that they can't rent or lease, we can help turn them into profitable enterprises."

The self storage metal building industry has been the fastest-growing sector of commercial real estate over the past 30 years. In 2006, primary self storage facilities - that is, where self storage is the primary source of income - earned a gross revenue of $22.6 billion.

That's a national average of $441,208 per facility.

Thanks to interior self storage systems, commercial property owners can join the industry by converting their structures into this type of steel building. Because retro self storage facilities are enclosed, companies help many self storage entrepreneurs create climate-controlled self storage to meet the commercial steel building demand for these products.

"You have liquor companies that need to keep wine at a certain temperature, or pharmacies that need to store medicine," said Brown. "It's a built-in market. Plus, many commercial buildings are already fitted for air conditioning, which makes converting them that much easier."

Construction on the facility can be completed fairly quickly. Typically, a specialized crew can convert a general steel building that's 100 ft. by 100 ft. into self storage space in a matter of weeks.