At Hamilton College in Clinton, NY, Trowel Trades Supply, Inc. was hired to locate a stone material to match the Unified Science Center to the surrounding stone buildings on campus. Ultimately, rubble stone from Rolling Rock Building Stone of Boyertown, PA, was selected.




“Much work went into getting just the exact blend of ashlar strips and roughly square/roughly rectangular stones in the right orientation to match the existing stone on the original building,” said Gene Pawlikowski of Trowel Trades Supply.

Over the years, three buildings on the campus of Hamilton College in Clinton, NY, had received additions with poor stone matches. To rectify this matter, the Hamilton College Director of Physical Plant, Steve Bellona, during negotiations with the construction manager, Barr & Barr, Inc., requested that a better stone match be found for the new Unified Science Center. With this mission in mind, Mark McElroy, project manager with Barr & Barr, Inc., asked Trowel Trades Supply Inc. of Colchester, VT, to look at the existing stone on the science building and come up with a good match. Ultimately, the company found the appropriate material through Rolling Rock Building Stone of Boyertown, PA.

The material, referred to as the “Hamilton College Blend A” rubble stone veneer, is a sandstone that features a full range of tan, rust and brown with some gray.

According to Gene Pawlikowski of Trowel Trades Supply, the architect's goal was to match the existing historic stone for color, texture and size. “Much work went into getting just the exact blend of ashlar strips and roughly square/roughly rectangular stones in the right orientation to match the existing stone on the original building,” he said.

Tom Murray from Colonie Masonry explained that installation of the stonework was completed in three separate phases over a two-and-a-half year period, with an average of 15 workers on the job.

Supplying the stone

According to Terrence Meck of Rolling Rock Building Stone, a custom blend of stone was quarried and supplied to match the existing buildings on campus. “We chose to put multiple custom blends together so they had options from which to make a choice,” he explained. “They selected the most natural appearance single-source stone blend - what is defined as 'Hamilton College Blend A,' a rough ashlar blend. It is quarried locally [in Pennsylvania] nearly year round. It is a sandstone with medium density.

According to Terrence Meck of Rolling Rock Building Stone, much work went into “close matching of product and labor to the desired finish application.”

“The college wanted to have a natural deep brown color, and so we did our very best to supply the stone to their color preference, without cutting the stone to a finer quality of ashlar pattern as would have been desirable for both the installation contractors and ourselves,” Meck continued. “This means the stone was selected and sorted to maximize these natural seam colors, as available in shape. Natural color also means natural shape. Only a very small percentage of rubble stone supplied was cut on hydraulic splitters, and this was used in constructing outside corners, or quoin details at windows and doorways.”

Since the project began over four years ago, Rolling Rock Building Stone has supplied more than 1,000 tons of 4- to 6-inch-thick bed rubble building stone for the campus, including the Unified Science Center and site walls. The company is also supplying additional stone for future campus development.



The main entrance to the science center features Salem Buff limestone panels, as well as a Crystal Gold granite base and entry pier. Both materials were supplied by Granite Importers, Inc. of Barre, VT. Furthermore, Vermont Unfading Green slate pavers - from Vermont Structural Slate Co. of Fair Haven, VT - were also utilized for the exterior design.

In addition to the rubble stone material, Salem Buff limestone was selected for building features including, sills, lintels, belt course, panels, coping and surrounds. Also, Crystal Gold granite was implemented for the wall base and steps. Both materials were supplied by Granite Importers, Inc. of Barre, VT. Furthermore, Vermont Unfading Green slate pavers - from Vermont Structural Slate Co. of Fair Haven, VT - were also utilized for the exterior design.

The rubble stone veneer was anchored to a block back-up wall.

Installing the stonework

According to Tom Murray from Colonie Masonry, installation of the stonework was completed in three separate phases over a two-and-a-half-year period, with an average of 15 workers on the job.

“We basically had to match the existing work, and we trained a few local bricklayers to the method needed to match the material,” explained Murray. “Once that was accomplished, we made pretty good time on it.”

Meck said the challenge when working with rubble stone is always the close matching of product and labor to the desired finish application requested by the design team and/or owners. “We are proud of our part in the success, and know the mason did an exceptional job in providing the completed finish the college sought,” he said. “The completed work appears far above expectation.”

The installers utilized guillotine-snapped stone for elements such as quoins.

Hamilton College
Unified Science Center
Clinton, NY

Architect: Einhorn Yaffee Prescott Architecture & Engineering (EYP), New York, NY

General Contractor: Barr and Barr, New York, NY

Stone Suppliers: Rolling Rock Building Stone, Boyertown, PA (Hamilton College Blend A); Granite Importers, Inc., Barre, VT (Salem Buff limestone, Crystal Gold granite); Vermont Structural Slate Co., Fair Haven, VT (Vermont Unfading Green slate)

Stone Installer: Colonie Masonry Corp. of Albany Inc., Schenectady, NY

Before Trowel Trades Supply's involvement, three buildings on Hamilton College's campus had received additions with poor stone matches.