Kohn Pederson Fox were the architects for Shearson Lehman Plaza, located at 388 Greenwich St. NYC, just a few blocks north of what was then The World Trade Center. The North and East facades of the 40 story skyscraper have been cleaned with D/2 Biological Solution. The building material is a fairly porous cast stone that that has attracted significant biological growth and airborne pollutants. Work was staged from as many as twelve 30’ swing scaffolds. Tishman Construction is overseeing the project. Brisk Waterproofing, a Division of Western Waterproofing was the façade cleaning contractor. Integrated Conservation Resources developed the cleaning specifications and supervised the work. D/2 Biological Solution was supplied by AH Harris.

(Photo: Gryffindor - CC BY-SA 3.0, edited by D/2 - CC BY-SA 3.0)

455 Central Park West's restoration was completed in 2005. Built by John Jacob Astor III in 1884 as the New York Cancer Hospital it lay in ruins for more than 25 years until the architectural firms of RKTB and Perkins Eastman were retained to restore and convert it into luxury housing. Jablonski Building Conservation was retained as building conservator and specified D/2 Biological Solution for removal of biological growth from the various facade stone and masonry substrates.

(Photo: Sarah Javier - CC BY-SA 3.0, Edited by D/2 - CC BY-SA 3.0)

Texas takes the Alamo very seriously - so it was no small decision to use D/2 in preserving this vital piece of Texan history.

(Photo: Nuggehalli2015 - CC BY-SA 4.0)

The Art Students League of New York was designed by Henry Hardenbergh and completed in 1892. Other Hardenbergh designed buildings include The Dakota, Plaza Hotel and Willard Hotel. Thomas Eakins and Augustus Saint-Gaudens were founding Board Members. Many of the 20th century's most important artists have studied here including Thomas Hart Benton, Jackson Pollock, Alexander Calder, Helen Frankenthaler, Roy Lichtenstein, Maurice Sendak and Robert Rauschenberg. Joan Berkowitz specified D/2 Biological Solution for the cleaning of the limestone façade.

(Photo: Jim Henderson - Public Domain, edited by D/2)

The Biltmore Estate is the largest private home in America. It was designed by architect Richard Morris Hunt for George Washington Vanderbilt. It took over six years to construct and was completed in 1895. Frederick Law Olmsted designed the 8,000 acres of cultivated landscape. The facades and much of the interior is Indiana Limestone. D/2 Biological Solution has been a significant part of their maintenance cycle for many years.

(Photo: 24dupontchevy - CC BY-SA 4.0)

On the National Register of Historic Places, Burial Hill in Plymouth, MA, is one of the oldest European cemeteries in America. Many of the original Mayflower Pilgrims are buried here including the first governor, William Bradford and Church Elder, William Brewster.

The project will span four years to be completed prior to the 400th Anniversary in 2020. The work includes conservation and cleaning of more than 2,269 historic stones. D/2 Biological Solution is the specified cleaner.

Stone conservator Ivan Myjer wrote the specification. Monument Conservation Collaborative (MCC) has been engaged to complete the work. A.H. Harris is the D/2 supplier. The Friends of Burial Hill raised the funds for the project through a Plymouth Community Preservation Commission Grant.

(Photo: Giorgio Galeotti - CC BY 4.0, Edited by D/2 - CC BY 4.0)

During its restoration of the 168 Benjamin Latrobe designed sandstone cenotaphs, the National Park Service chose D/2 to do the cleaning.

(Photo: courtesy of the US Capitol - Public Domain, edited by D/2)

Frank Lloyd Wright's Taliesin estate is a shrine to many architects. Staff there use D/2 to combat biological growth.

(Photo: QuartierLatin1968 - CC BY-SA 3.0, Edited by D/2 - CC BY-SA 3.0)

In 1939 journalist Loren Pope and his wife Charlotte Pope commissioned Frank Lloyd Wright to design a new home. The design followed Wright's Usonian principles and was completed in 1941. The "Usonian" house was developed by Wright as a means of providing affordable housing for people of moderate means.

Wright employed wood cladding as an affordable and easily workable material into his design. After almost a century, the wood cladding needed some help - that's where D/2 came to the rescue.

D/2 is often used to control biological growth on wood subject to moisture and was used here to remove bio growth without harming the sensitive historic fabric of this Wright gem.

(Photo: Cliff - CC BY 2.0, Edited by D/2 - CC BY-SA 3.0)

There's no job too big for D/2. The ornamented facades of this 400,000 sq ft Chicago Landmark were cleaned from top to bottom with D/2.

(Photo: Museum of Science & Industry - CC BY 2.0, Edited by D/2 - CC BY-SA 3.0)

The city walls of San Juan, Puerto Rico are a part of the San Juan World Heritage Site. Construction of the walls began in the 1630s, with construction continuing for the next 150 years. They average 42 feet in height and are also about 42 feet thick at their base. The National Park Service began cleaning the walls with D/2 Biological Solution more than 8 years ago. The current project includes two distinct sections of the wall known as the Santa Elena and the San Augustin. Together they extend 2,600 feet. The Atlanta office of architects Lord Aeck Sargent have been retained by the NPS to write the cleaning specifications.

(Photo: MJCdetroit - CC BY-SA 3.0, Edited by D/2 - CC BY-SA 3.0)

The National Park Services trusts D/2 to keep America's iconic White House looking white.

(Photo: Matt H. Wade - CC BY-SA 3.0, Edited by D/2 - CC BY-SA 3.0)

More than 4 million people visit this hallowed memorial each year. D/2 is used to keep its Yule Marble looking flawless.

(Photo: Alex McLeod - CC BY 2.0, edited by D/2 - CC BY-SA 3.0)