(CNN) — Why build a bigger cruise ship when you can just cut one in half and add an extra 15 meters to the middle?

That seems to be the thinking at cruise company Silversea, which has begun an eye-popping project to stretch its luxury cruise ship Silver Spirit.

The elaborate engineering feat, underway at the Fincantieri Shipyard in Palermo, Italy, requires over 500 skilled workers and will take up approximately 450,000 man hours.

A prebuilt 15-meter extension (almost 50 feet) has already been inserted with "military precision" to stretch Silver Spirit from 195.8 to 210.7 meters.

The 36,009-ton ship is now being carefully reconnected to make it ready for sea travel

Described as a "rarely performed feat of maritime architecture," the operation is the first of its kind involving a luxury cruise ship, according to Silversea.

Ambitious project

Silver Spirit will grow from 195.8 to 210.7 meters once the work is complete. Silversea

The renovation requires approximately 846 tons of steel, 110,000 meters of cabling and 8,000 meters of piping and is believed to come with a $100 million price tag.

Once completed, the ship's capacity will increase by around 12%, and Silversea (whose headquarters are based in Monaco) aims to "create more space in public areas" and "enhance Silver Spirit's facilities."

"Witnessing these breathtaking phases of the Silver Spirit lengthening project has filled us with pride and excitement," says Barbara Muckermann, chief marketing officer of Silversea.

She says the work will upgrade Silver Spirit to more closely match the magic of its newer flagship vessel Silver Muse, which took the sea in 2017.

"The lengthening and refurbishment of Silver Spirit will replicate the modern elegance of our latest vessel to make for a more luxurious traveling experience," Muckermann adds.

"We are eager to share the new and improved layout of our cherished ship with our valued guests.'"

New and improved facilities

Call it recycling? The Silversea cruise ship company is spending over $100 million to make a very big cruise ship out of a smaller one they already own.​

The extra space will make room for a new eight-restaurant formation as well as increased outdoor seating, an expansion of the pool deck and 34 new suites.

Silver Spirit's sky deck will also increase in length and a new aerobics area is to be fitted outside.

Other new additions include a spa, a free weights room and two new public spaces.

The ship's current suites are also to be refurbished. Silversea says it's already donated 11 containers of furniture -- including sofas, chairs, curtains and computers -- to hospitals, nursing homes and schools in Chania, Crete.

Silver Spirit first set sail in 2009 and served as Silversea's largest luxury ship until Silver Muse was launched in April 2017.

The privately owned luxury cruise line's other vessels include Silver Wind, Silver Shadow, Silver Whisper as well as expedition ships Silver Explorer, Silver Galapagos, Silver Discoverer and Silver Cloud.