College of Engineering News • Iowa State University

“Lost art” brought back: Marston Hall’s unique Venetian terrazzo revealed and restored

Terrazzo flooring medallion
Terrazzo flooring medallion

The atrium floor of the 120-year-old Marston Hall had an entirely “new” appearance when Cyclone Engineers returned after winter break.

While touring Marston with construction crews repairing water damage, W. Samuel Easterling, James L. and Katherine S. Melsa Dean of Engineering, spotted the original Venetian terrazzo, which features a medallion in the center. He was determined to restore it.  

“I thought ‘why is this original feature of Marston under carpet? This floor deserves to be seen and enjoyed by everyone,’” said Easterling.

New chance for ancient art

Before Marston Hall’s complete renovation in 2016, the original terrazzo flooring could be seen on the ground floor. But it was rough condition and wasn’t refurbished during the renovation due to both project and budget limitations. 

In the eight years since the renovation, much has been learned about how to best restore terrazzo, making restoration now possible. 

Iowa State’s Facilities Planning and Management knew they would need an expert to restore the original terrazzo flooring, leading them to Dario Lenarduzzi, a terrazzo and mosaic specialist based in West Des Moines.  

The Lenarduzzi family and marble mosaic share their origins in Friuli, Italy, where the Scuola Mosaicisti del Friuli is located. 

“My father attended this school before coming to America. I go to the school every year, and my cousin Maurizio Lenarduzzi is a teacher at the school,” said Lenarduzzi.  

Timeless terrazzo meets modern techniques

Lenarduzzi quickly determined that the Marston flooring isn’t a typical terrazzo but a rarer Venetian form that uses pieces of tile about an inch thicker than a modern terrazzo, making Venetian terrazzo more durable and longer lasting.  

“Venetian terrazzo is a lost art,” according to Lenarduzzi. “The Venetian floor at Marston Hall is especially unique because it was originally done before 1910, before electric grinding machines were used.” 

At that time, the terrazzo was ground by hand using a “galera,” a piece of stone attached to a long handle of iron pipe that was pushed and pulled back and forth by a workman. 

“Galera, translated in English, means jail because the manual labor involved with this was like being in jail,” said Lenarduzzi. 

Now, the process of restoring this mosaic and terrazzo includes grinding the entire floor with a terrazzo machine that has 60-grit diamonds.  

“We then grouted to fill all holes, voids, and cracks. We patched the mosaic floor. We then polished 100, 200, 400, and 800 wet diamond finish and applied a simple stone protector,” said Lenarduzzi. 

For another 120 years

Lenarduzzi’s finishing process ensures that the stone will not need to be waxed or stripped in the future because it is in its natural state.

“What a beautiful symbol of Iowa State engineering’s long history,” said Easterling. “I hope when students and alums see the terrazzo, they are proud to be part of the Cyclone Engineering tradition.” 

“So much has changed in the world in the 120 years since the flooring was originally placed, but all along the way, Cyclone Engineers have been working hard to solve the tough problems. That will be true for the next 120 years, too!”

Terrazzo flooring pattern