Since 2010, OPN has led the completion of six projects at Terrace Hill. The firm’s restoration and renovation of the 1869 National Historic Landmark residence for the governor and his family, started in 2009 as a sub-contractor under KJWW Engineering. OPN was part of the team that executed the addition of a geothermal system to the more than 150-year old mansion. Commercial Kitchen: In 2010, the firm was hired to transform the outdated and undersized residential kitchen in the basement into a commercial kitchen. The renovation adhered to both historic preservation regulations as well as current food service codes. Front Portico: Deteriorated original mill-work and roofing from previous restorations were modified and restored. Security Gate: The pre-existing main entrance was unsecured with a narrow metal gate that could be circumvented easily. OPN assessed the technological and security needs of the site and staff and installed a new gate that significantly increased the security of the estate. Third Floor + Window Restoration: The governor’s main living area, most intensively the kitchen and bath, was renovated and restored. Exterior elements were also carefully restored, most notably the windows and exterior decorative mill-work at third, fourth, and fifth floor, as well as masonry chimneys and towers. Throughout the process, the team thoroughly researched and analyzed all existing materials, colors, and finishes to determine, and wherever possible replicate, the original conditions. Original materials were diligently saved and cataloged to preserve as much original building fabric as possible, which maintained the historic integrity of original character-defining features of the home both inside and out.