The remarkable transformation of the Empire State Building in New York’s Lower Manhattan skyline, from being an old energy guzzling skyscraper to becoming one of the most energy efficient in the city has been drawing headlines regularly now. A massive 3- year makeover of the building has meant that the 81 year old building is still able to attract new tenants, who are also willing to shell out higher rents.

While the neighboring One World Trade Center could be one its way to becoming the tallest skyscraper in New York, it has been Empire State Building which continues to be the cynosure of all eyes even today, thanks to the retrofit. The company’s retrofit success story has meant that today leading names like Siemens AG, Honeywell International Inc, AG and United Technologies Corp and Johnson Controls Inc are eyeing the about US$ 6 billion retrofit market.

According to estimates of industry experts, the new US$13 million retrofit would pay for itself within three years, thanks to a 38% reduction in the building’s annual energy consumption.

The innovative idea adopted by Tony Malkin, owner of the Malkin Group, which owns the building, also enabled a lot of savings. For example on e of his ideas was to refurbish the glass in the building’s windows instead of replacing them. What it meant was that US$700 was spent on cleaning and insulating each window, instead of paying US $2500 for replacing each of the 6,514 windows. A window refurbishing factory was actually set up on the building’s fifth floor for the purpose, adding to the cost-effectiveness of the process.