PALO ALTO, CA-Many of today’s commercial buildings are being constructed with energy efficiency and economically sound principles in mind. LEED certifications have become practically commonplace, and architects and developers are creating properties that are cleaner and greener than ever.

But what about existing buildings, particularly those constructed more than a couple of decades ago? Retrofitting these properties to become more sustainable can be extremely costly, and in the current economy many owners don’t have the means to do complete overhauls. Fortunately, options do exist for making buildings greener without going bankrupt. Some involve taking advantage of existing financing programs, while others deal with reexamining operating procedures.

“There’s an increased interest in sustainable retrofits because there’s a lot of older product out there,” Michael Polentz, co-chair of the real estate and land use practice at Manatt, Phelps & Phillips in Palo Alto, CA, tells GlobeSt.com. “The people tracking the numbers are suggesting that about one-third of all retrofitting will be for energy or conservation efforts. There are some large national contractors who say that equates to north of $18 billion over the next three years. The challenge: how to finance the projects. A lot of people are struggling with this.”