public buildings

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adaptive use

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historic contexts

The Roslyn Grist Mill
Roslyn, NY
Client: Nassau County Department of Recreation and Parks

Project Type: Historic structure report; feasibility study, stabilization

The Roslyn Grist Mill, circa 1898.


The Roslyn Grist Mill, located at the head of Hempstead Harbor, was erected between 1715 and 1741 and remained a working mill for two centuries, playing an important role in the development of the village. In 1790, George Washington noted a visit to the mill in his diary. The building, which is listed on the National Register of Historic Places, had deteriorated over the years from lack of maintenance, the high water table, and periodic tidal flooding.

As the first step in the restoration, John G. Waite Associates, Architects prepared a historic structure report incorporating a history of the building and measured drawings furnished by the Roslyn Preservation Corporation. The historic structure report provided detailed conservation recommendations and priorities, advocating raising the building to mitigate water problems and restore it to the level of the street.  JGWA also completed a feasibility study that prioritizes the restoration plan, and provides construction phasing, logistics, and probable cost information.  This updated report will allow further stabilization and conservation work to begin on the mill.

In January of 2020, the Roslyn Grist Mill was raised four feet above street level so that the new foundation can eventually be poured. While the mill was being lifted, workers quickly added sections of timber cribbing to account for the additional height. The new, expanded headroom will allow workers to excavate the existing foundation and begin construction on a new water-tight foundation. Timber frame specialists have already begun to remove and restore deteriorated columns and support beams.



Upon completion of the foundation and timber restoration later this year, the mill will be lowered four feet to street level in order to provide safe public access to the mill for future use as an education center. It will be the first time the building will be at street level in over 100 years, when the roadbed was raised in the early 1900s.